Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Robin Bowes;192575 Wrote: > > ??? > > It appears to me that was *exactly* what they were doing? Are you > suggesting that the testing was flawed? That's not at all what they were doing. They played some musical selections on two amps (invisible to the listeners), labelled A and B or something, and then asked which the listeners preferred. In such a situation people will almost always express a preference even if A and B are identical, and if asked will construct elaborate (and false) reasons for their choice. In fact this setup is almost identical to that of a study I know, where the researchers were interested in this psychological effect (so in the study the options were identical but disguised). So yes, the test was flawed - the results are meaningless (for audio at least) if the participants couldn't actually perceive a difference. They should have checked that first, which would have been very easy to do given their setup. > > Meaning? > As Skunk said - that probably all or most of the amps couldn't be distinguished in an ABX test. That's been shown over and over again with many different types of amps. Their results are consistent with that, as most of the votes were split about evenly. One exception might be the Panny, which I think does an A->D and a D->A. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Robin Bowes;192575 Wrote: > > Meaning? > > R. Meaning after the comparison, while the sounds are fresh in their head, put someone in the listening seat and ask them to blindly answer the question, 'which one is playing?'. Opaqueice is suggesting it would be a guessing game. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
opaqueice wrote: > TCM;192497 Wrote: >> 'The Great Digital Amp Shootout 2007' >> (http://www.stereomojo.com/SHOOTOUT2007INTEGRATEDS.htm) > > The $139 15W amp wins - that's hilarious. Too bad they didn't do a > test to see whether anyone could actually tell the difference between > any of them - that would have been more interesting, ??? It appears to me that was *exactly* what they were doing? Are you suggesting that the testing was flawed? > although the results are pretty easy to guess Meaning? R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
TCM;192497 Wrote: > 'The Great Digital Amp Shootout 2007' > (http://www.stereomojo.com/SHOOTOUT2007INTEGRATEDS.htm) The $139 15W amp wins - that's hilarious. Too bad they didn't do a test to see whether anyone could actually tell the difference between any of them - that would have been more interesting, although the results are pretty easy to guess -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
TCM;192497 Wrote: > 'The Great Digital Amp Shootout 2007' > (http://www.stereomojo.com/SHOOTOUT2007INTEGRATEDS.htm) Good to see the little Trends amp did so well. Shame the presentation of the report is such a shambles. I didn't see any mention of the source, but the implication is that they were using analog in, which doesn't really let the Panasonic exercise its (theoretical) strength. The input's being turned to a PCM stream internally by some crappy ADC. I'm not convinced about classifying the Panny as class D, but terminological pedantry has already proven unpopular in this thread. Similarly, describing many of these as "digital amps" is questionable. ... I still haven't revisited the Panny for further comparisons. Having a toddler, working for a living etc., get in the way... -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
'The Great Digital Amp Shootout 2007' (http://www.stereomojo.com/SHOOTOUT2007INTEGRATEDS.htm) -- TCM 'Squeezebox 3' (http://www.slimdevices.com/pi_squeezebox.html) -> 'Trends Audio TA-10.1' (http://www.6moons.com/audioreviews/trends/ta10.html) -> 'QLN QuBiC 121' (http://www.minhembio.com/produkt/163409) http://www.last.fm/user/ThisCharmingMan http://www.savethestreams.org TCM's Profile: http://forums.slimdevices.com/member.php?userid=702 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;189257 Wrote: > I have to correct myself here in my mp3 vs FLAC tangent-upon-a-tangent > on this thread. > > What I actually used was "lame --alt-preset extreme", which is supposed > to be equivalent to -V0. However, I also used a version of lame that is > not current (3.91). I downloaded the latest (3.97) and the "-V0 > --vbr-new" setting gave me something -far- superior. I only managed a > _very_ brief listen, and the differences between this, "-b 320", and > the FLAC were *not* stand-out obvious. I have to give it a proper > listen later. > > The previous VBR encoding had sections as low as ~128kbps. In the end it just goes to show that lossy is not to be trusted to sound indistinguishable from lossless. I'd never archive material for the future in a lossy format. (Unless originally recorded as such, of course.) -- P Floding No, I didn't ABX it. And I won't even if you ask me. (Especially not if you ask me.) P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187811 Wrote: > I tried one track for a (blind) test to compare FLAC to mp3 (lame -V0 > VBR, avg ~240kbps), and the difference was instantly and clearly > apparent. I have to correct myself here in my mp3 vs flac tangent-upon-a-tangent on this thread. What I actually used was "lame --alt-preset extreme", which is supposed to be equivalent to -V0. However, I also used a version of lame that is not the latest and greatest (it may have been 3.93). I downloaded the latest (3.97) and the "-V0 --vbr-new" setting gave me something -far- superior. I only managed a _very_ brief listen, and the differences between this, "-b 320", and the FLAC were *not* stand-out obvious. I have to give it a proper listen later. The previous VBR encoding had sections as low as ~140kbps. -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Indeed the "is it an amp" question is purely technical and irrelevant to the end user. Even if it isn't, most people will call it an amp for convenience if nothing else. We've probably done that to death here. The interesting technical point is that there is no analog gain stage in the unit. regalma1;187696 Wrote: > The real question is, does it sound good. The reviews I have seen have > varied. That makes sense as it is likely any class D unit is going to > be very load sensitive, what with the smoothing capacitors and the high > frequency filters on the output. I read a very extensive review of > several high end class D amps in Stereophile. It was pretty apparent > that how they are going to perform is dependent on the reactive element > of the cables and speakers they are connected to. Opinions of the > various reviewers in the article ranged all over the place. The jury's still out in my case. It's very hard to evaluate, and utterly impossible for me to do it blind. Transferring speaker cables etc... I'll plug in the Creek again in a week or two for a long-term impression when I find some time and some patience for an evening of swapping. It's very clear to me that it has more resolution than my Creek amp (4330, plus Epos ES12 speakers). However, I haven't decided what I think about the overall musical experience, particularly the tonal balance. The Creek is definitely warmer, even though I thought of it as pretty neutral before. I have to decide whether I feel like I was mistaken, or the Panny is unnaturally thin. It could be related to difficulty driving the speakers' frequency-varying loads, with its class D-like output stage, but that sort of speculation just unhelpfully feeds back into the perception. I feel the clarity really is showing up the quality of the source. I used some Elliott Smith for comparisons, and now my conclusion is that his production values weren't great. e.g. I thought some sibilants were terrible, and blamed the amp, but then listened to other recordings and there were no problems with sibilants. (Which makes me wonder whether a theoretical ultimate "transparent" system could actually be a liability in the real world of imperfect recordings which you still want to listen to?) Surprisingly for anyone only passingly familiar with their ilk, I listened to The Wedding Present's Seamonsters which, being mostly heavily distorted guitars, doesn't seem like a candidate for critical equipment listening. However, it is and it really shone. The production is superb and there's minimal compression. This can be annoying if you hit a track on shuffle as some have a peak volume of 80% or so, much of it way below that, because the producer -didn't- turn everything up to 11 and left headroom for tracks that should be louder, to be louder. I tried one track for a (blind) test to compare FLAC to mp3 (lame -V1 VBR, avg ~240kbps), and the difference was instantly and clearly apparent. I expected to sit down and patiently compare the two and slowly generate an opinion. In the end I listened to the first 3 notes (minimally distorted guitar) a couple of times each and said, "this one is -definitely- the FLAC", and I was right. The texture and detail was clearly significantly superior, and it was so obvious that I didn't see any point in trying other tracks. Up until now, I mostly listened to mp3s (background listening, portable player etc.), but sat down with a real CD in my Arcam player when I wanted a treat. I'd read on the likes of the HydrogenAudio site that -V1 would probably be transparent, and only quickly compared it on a pretty weak DAC (Stereolink USB DAC into the Creek) before. So I have lots of experiments to do: Try up to 320kbps CBR mp3s and see whether I can distinguish them from FLAC... Try the Creek again after listening to the Panny for a while. Try the same mp3 tests on the Creek and see if it's so clear (ditto on my portable player)... Try out the bi-amping option on the Panny... -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187666 Wrote: > It doesn't "also have a DAC", it -is- a DAC. That is the point. The > digital PCM input is converted to a PWM stream in the digital realm, > and then the pulses are smoothed out directly for the speaker output. > This is definitely an over-simplification, as I originally pointed out, > and in fact that was the truly interesting area for discussion. > > To reiterate: this unit is not a DAC and amplifier integrated into one > box. On the contrary, to provide analog inputs, it runs them through > an ADC to generate _PCM_ input. In that case it, in composite, forms > what is effectively a variant of a class D amp, but with digital > conversion into the PWM stream. > > I can't imagine you're suggesting that, you can compare a digital input > power and the output analog, with a higher powered output than input > represents gain- that the gain of the Panasonic can be measured in > terms of the power of the S/PDIF input vs the speaker output? > > The issue is that there is nowhere in this amp where you could find an > analog signal to compare with the output, to measure gain. That's one > indication that this isn't an amp. > > As I said before, there will be a place where a binary digital signal > is turned into another, higher power binary digital signal, but that's > never really been considered amplification in the past has it? - that's > switching. > > So, to call these amplifiers, needs a new and very loose interpretation > of what an amplifier is, no matter what people's gut feelings may tell > them about what it looks like, or the what position it sits in in their > hifi cabinet. Sorry, but I believe you are just complicating things. An amp is an amp is an amp. No matter how it is implemented. That non-technical consumers tend to think of "an amp" in one specific way has very little to do with anything. They just have to re-learn. -- P Floding No, I didn't ABX it. And I won't even if you ask me. (Especially not if you ask me.) P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
As technology changes definitions sometimes don't keep up. If it has gain then it is an amplifier in the general sense. Gain is how much power (watts) going in divided into how much is going out. At least that is gain in watts. You can have gain in volts, etc. This is not simply a convertor changing digital to pulse modulated to analog. There is a lot of gain. Otherwise what is the point of the device. Like I said, it is a matter of definition. No point in us fighting over it. Since everyone appears to be calling it an amp that is what is likely to become the convention, no matter what either of us think. The real question is, does it sound good. The reviews I have seen have varied. That makes sense as it is likely any class D unit is going to be very load sensitive, what with the smoothing capacitors and the high frequency filters on the output. I read a very extensive review of several high end class D amps in Stereophile. It was pretty apparent that how they are going to perform is dependent on the reactive element of the cables and speakers they are connected to. Opinions of the various reviewers in the article ranged all over the place. -- regalma1 regalma1's Profile: http://forums.slimdevices.com/member.php?userid=6658 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
regalma1;187649 Wrote: > You measure the total power level going in and the total going out. If > the latter is greater than the former there is gain. You have an amp. > The fact that the Panasonic also has a DAC doesn't really change that. > If that was the case then a standard amplifier with a digital input > (feeding a DAC) would not be an amp. It doesn't "also have a DAC", it -is- a DAC. That is the point. The digital PCM input is converted to a PWM stream in the digital realm, and then the pulses are smoothed out directly for the speaker output. This is definitely an over-simplification, as I originally pointed out, and in fact that was the truly interesting area for discussion. To reiterate: this unit is not a DAC and amplifier integrated into one box. On the contrary, to provide analog inputs, it runs them through an ADC to generate _PCM_ input. In that case it, in composite, forms what is effectively a variant of a class D amp, but with digital conversion into the PWM stream. I can't imagine you're suggesting that, you can compare a digital input power and the output analog, with a higher powered output than input represents gain- that the gain of the Panasonic can be measured in terms of the power of the S/PDIF input vs the speaker output? The issue is that there is nowhere in this amp where you could find an analog signal to compare with the output, to measure gain. That's one indication that this isn't an amp. As I said before, there will be a place where a binary digital signal is turned into another, higher power binary digital signal, but that's never really been considered amplification in the past has it? - that's switching. So, to call these amplifiers, needs a new and very loose interpretation of what an amplifier is, no matter what people's gut feelings may tell them about what it looks like, or the what position it sits in in their hifi cabinet. -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
You measure the total power level going in and the total going out. If the latter is greater than the former there is gain. You have an amp. The fact that the Panasonic also has a DAC doesn't really change that. If that was the case then a standard amplifier with a digital input (feeding a DAC) would not be an amp. By the way, class D amps still put out a analog signal. The difference is that they amplify the signal using on/off switching and timed pulse lengths. They then smooth out the pulses to create a conventional analog signal. Don't confuse the D in class D for digital. There is no relationship between the two. -- regalma1 regalma1's Profile: http://forums.slimdevices.com/member.php?userid=6658 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
My original intention was to highlight the interesting quirks of the technology and possibly initiate some edifying discussion. That doesn't seem likely to happen. I'm sorry I got onto the issue of terminology - I just thought it was an amusing semantic quirk. P Floding;187629 Wrote: > http://en.wikipedia.org/wiki/Electronic_amplifier > > Check spcifically "Class D". Yes, in as much as I have implied that a T-amp is not really an amp (i.e. not much), I am wrong with respect to conventional terminology. I'd still argue the T-amp is not -strictly- an amplifier internally, but since the end result is an amplified version of the input signal, it's reasonable to call it an amplifier. Hence: jimmyfergus Wrote: > Yes, for analog input, if you consider the unit as a whole, as with the > T-amps, it is arguably an amplifier in the abstract sense None of which indicates how a digital input with an analog output fits the definition of an amplifier. The Panasonic is not a class D amp. Its output stage resembles the output stage of a class D amp, but a class D amp takes, and processes, analog input and that crucial difference is what makes it reasonable to call them amplifiers. The Panasonic (TI PurePath) does not. There is no point internally where you could place an oscilloscope probe, even within a chip, and see a lower power version of the output signal. The only conceivable point where you can see a higher power signal matching a lower power input is in the digital realm - and that is achieved with switching, not amplification. If that is amplification, then so is every relay. -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187609 Wrote: > by that logic, a DAC is an amplifier. A DAC does have op-amps (operational amplifiers) to produce usable analog output. They could be considered pre-pre-amps. Some people argue that they are the most critical amps in the entire audio reproduction process for digital sources. Nevertheless, it's a semantic issue. Practically speaking, I would not consider a DAC to be an amplifier. -- TiredLegs TiredLegs's Profile: http://forums.slimdevices.com/member.php?userid=6201 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187609 Wrote: > Sorry, no. By that logic a relay is an amplifier. All the transistors > in the Panasonic amp are used as switches - they -all- are either on or > off, just like in a computer CPU. Nobody argues a CPU is full of > amplifiers. > > Also, by that logic, a DAC is an amplifier. Is anything electrical not > an amplifier (some with gain < 1)? http://en.wikipedia.org/wiki/Electronic_amplifier Check spcifically "Class D". -- P Floding No, I didn't ABX it. And I won't even if you ask me. (Especially not if you ask me.) P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
P Floding;187591 Wrote: > So the panasonic doesn't accept an analogue input? Yes, for analog input, if you consider the unit as a whole, as with the T-amps, it is arguably an amplifier in the abstract sense, even though at no point does amplification actually occur internally. Internally they're an ADC connected to a DAC. jimmyfergus Wrote: > The Panasonic and its ilk, on the other hand, *with digital input*, I > think is not an amplifier in any sense However, I was talking about digital input, as I said. Whether you consider it as an abstract whole, of you look at its internals, it's a DAC with no amplifiers involved. In film photography, when you take a negative and made a print, you use an "enlarger". If you scanned a photo and printed it on your printer, is it accurate to call your scanner + computer + printer an "enlarger"? Now use a digital camera; again, is it an "enlarger"? If so, the Panasonic (need I say, -with digital input-) is an amplifier. Just because the end result is the same, it doesn't make the tools which achieve it equivalent. The system which takes digital audio encoding and produces sound is not an amplifier - it typically -includes- an amplifier. That does not mean that all processes which produce sound from digital encodings must use amplifiers. -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus wrote: > P Floding;187587 Wrote: >> Anything that "amplifies" is an amplifier, no matter how it's done. So, >> yes, they are all amplifiers. > > Nothing in the Panasonic "amplifies"... The direct output of a DAC in > the Panasonic is connected to speakers. There is no point, buried > within a chip or in an external component, where a low level analog > signal is converted into a higher level one. Unless digital to analog > conversion is a form of amplification? It seems more akin to > transduction to me. > > If it's an amplifier, then so is a relay. If taking a binary signal > and producing a mathematically equivalent binary signal with a > different voltage is amplification, then yes, it is an amplifier and a > CPU is full of amplifiers. Perhaps a calculator is also then an > amplifier, when you use the multiplication key... Of course it's an amplifier. It takes an digital input in a standard format, e.g. SPDIF, which is referenced to a certain voltage level, and it produces an output voltage much higher that that reference level. Ergo, it's an amplfier. R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187590 Wrote: > Nothing in the Panasonic "amplifies"... The direct output of a DAC in > the Panasonic is connected to speakers. There is no point, buried > within a chip or in an external component, where a low level analog > signal is converted into a higher level one. Unless digital to analog > conversion is a form of amplification? It seems more akin to > transduction to me. > > If it's an amplifier, then so is a relay. If taking a binary signal > and producing a mathematically equivalent binary signal with a > different voltage is amplification, then yes, it is an amplifier and a > CPU is full of amplifiers. Perhaps a calculator is also then an > amplifier, when you use the multiplication key... So the panasonic doesn't accept an analgue input? -- P Floding No, I didn't ABX it. And I won't even if you ask me. (Especially not if you ask me.) P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
P Floding;187587 Wrote: > Anything that "amplifies" is an amplifier, no matter how it's done. So, > yes, they are all amplifiers. Nothing in the Panasonic "amplifies"... The direct output of a DAC in the Panasonic is connected to speakers. There is no point, buried within a chip or in an external component, where a low level analog signal is converted into a higher level one. Unless digital to analog conversion is a form of amplification? It seems more akin to transduction to me. If it's an amplifier, then so is a relay. If taking a binary signal and producing a mathematically equivalent binary signal with a different voltage is amplification, then yes, it is an amplifier and a CPU is full of amplifiers. Perhaps a calculator is also then an amplifier, when you use the multiplication key... -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Mark Lanctot;187321 Wrote: > Isn't it supposed to run hot though? > > There may be problems putting it into a confined space with little or > no ventilation. It get a little warm, though it's not that hot. I believe it will generate a lot less heat than a conventional class A/B amp, because it's much more efficient. It also has A/B speaker outputs. I'm pretty sure you can set the relative volume output to them too, though there's no independent real-time volume control. Skunk Wrote: > In a lame attempt to get back on topic, the $30 t amp is a low to high > level converter :-) Yeah, there's no amplifier in there, though the unit as a whole is arguably an amplifier, at least at an abstract, black-box, level. As I understand it, internally the T-amp is at some level an ADC connected to a DAC with speaker level outputs, where the digital intermediate signal is a form of PWM. The Panasonic and its ilk, on the other hand, with digital input, I think is not an amplifier in -any- sense (in spite of it having the word on the front). It takes digital bits, manipulates them, and directly generates speaker level analog output from it. There's no point when a small wiggle is made into a big one. Unless you could call a relay, switch, or DAC an amplifier... In my shaky understanding that's the -theoretical- benefit of digital amps. They take a pulse width modulation, where a signal level of 30% is presented as a single bit signal that's high for 30% of the time, and then apply a low pass filter to get an analog signal with a 30% level. Thus a simple digital stream plus a low pass filter sidesteps all the ugly quirks of a solid state transistor amplifier. Voilà, perfect sound ;). ahem. What I don't understand though (ok, I don't understand most of it), is how they do it without an extremely high clock frequency. To get the pulse codes to encode 16 bits @ 44.1kHz, I'd have thought that you'd need a PWM clock 44100 * 65535 Hz, or about 3GHz, and they don't. They use, I believe, 384kHz, and claim that can output 192kHz sound, which would be an appropriate clock for PCM, not PWM. If my simplistic understanding were right, the amp would theoretically only be able to output 3 bit resolution at 44.1kHz output, and so would surely sound rubbish. It doesn't, so there's a lot going on that I don't understand. That's not news :). -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
courtesy Roger Russell: http://www.roger-russell.com/wire/wire.htm#resistancehigh 18 AWG TWO CONDUCTOR Copper 8 feet max 2ohm 16 feet max 4ohm 24 feet max 6ohm 32 feet max 8ohm Also, it occured to me that optical might be a better connection digitally in-wall, as it's not a big antenna and may be easier to pull through. I haven't researched it's durability for this use though. In a lame attempt to get back on topic, the $30 t amp is a low to high level converter :-) -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
TimothyB;187425 Wrote: > Thanks, Skunk, > > [Re using a 5.1 amp] Since the SqueezeBox is going to be my only signal > source, I was kinda figuring that the left channel would go to left > front and rear and the right to right front and rear. That way I could > balance/fade between two pairs of stereo speakers. Using two amps, I'd > have to split the input signal. > Sorry, I didn't mean use two amps. I think a receiver will work great. You'll just have to experiment with what sounds best as far as which channels go where and how to best balance them. Also, I realized I didn't mention low to high level converters, which is obviously what he must've been assuming you were going to use. Then you can connect RCA from squeezebox to converter, and into the wall. The converter should be fairly cheap so it's worth a go. I assume you'd need one on the other end, but I did see an audio source amp that had speaker level inputs. I'd try to use the digital connection rather than purchasing converters, if you get the digital amp. That's just one coax cable that would have to be pulled through. Generally the way it's done is fish a stiff wire through the chase and tape your cable to that, so nothing sticks out to get caught on and it's sealed up from debris, then pull the coax through section by section. Easier than it sounds really. Good luck and post some pics :-) -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Thanks, Skunk, [Re using a 5.1 amp] Since the SqueezeBox is going to be my only signal source, I was kinda figuring that the left channel would go to left front and rear and the right to right front and rear. That way I could balance/fade between two pairs of stereo speakers. Using two amps, I'd have to split the input signal. I chose to place the amp in the center of the kitchen, so none of the runs should be longer than 20 feet. It's really unfortunate that the walls are buttoned up (and painted) now. I guess I'll try out what I've got, and if the sound is bad, I'll rip things open again and put in 20' of the blue jean stereo audio cables Mark recommended in another thread. If I'm going to go to that much trouble, will the current 18 gauge wire be okay for the speakers in a 20 foot run? -- Timothy -- TimothyB TimothyB's Profile: http://forums.slimdevices.com/member.php?userid=4868 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
TimothyB;187381 Wrote: > > One thing I'd like to do is to be able to balance one pair of speakers > vs. the other. I was thinking about getting a 5.1 amp and wiring the > speakers as front & rear sides. You'll have to make sure it isn't sending only rear speaker sounds to one room, while front spk sounds to another. Better might be a 2 channel amp that has an A/B speaker selector. An impedance controlled multi zone volume control can be bought if you don't have A/B speaker outputs, but those are around $150 alone... > > I'd planned on putting the amp(s) in the high cabinet over the fridge, > so they wouldn't be taking up "hot" (i.e. more accessible) storage > space. Have run 3 sets of speaker wires to that spot, one set for each > pair of speakers and one to run from the SqueezeBox to the amp. (All > using 18-gauge wire, because that's what the electrician put in.) Speaker wire isn't usually meant to transmit low level analog or digital signals from squeezebox to amp, so ideally you'd have coax or cat5 for long SPDIF/RCA runs (and use a balun to convert impedance for transmission on analog signals), in place of the third set of speaker cables. If it's an easy run you could tape the coax/cat5 to the speaker wire really well and pull the cat5 through to where you need it. That may/not work, so you might call the guy and ask if he'll do it, possibly free/cheap if you told him you wanted to run low level signals from here to there and he used speaker wire. If it's not too long of a run for L&R RCA cables (which can be purchased bundled together) then you can save yourself the cost of baluns, but I think 30-40+ feet would be a long way for unbalanced RCA. I suppose the first thing you need to know for sure is whether your amp will have digital input or analog RCA only. Either could likely be run 20-30(?)' length without using the baluns, so if the squeezebox can be closer to the amp then all the better/easier. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
A little more info: The two pairs of speakers are at opposite ends of the (long, narrow) kitchen. One pair is over the breakfast bar, and the other is near the dining room. One thing I'd like to do is to be able to balance one pair of speakers vs. the other. I was thinking about getting a 5.1 amp and wiring the speakers as front & rear sides. I'd planned on putting the amp(s) in the high cabinet over the fridge, so they wouldn't be taking up "hot" (i.e. more accessible) storage space. Have run 3 sets of speaker wires to that spot, one set for each pair of speakers and one to run from the SqueezeBox to the amp. (All using 18-gauge wire, because that's what the electrician put in.) -- Timothy -- TimothyB TimothyB's Profile: http://forums.slimdevices.com/member.php?userid=4868 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;187307 Wrote: > Alternatively, if you can stump up to about $200, and don't mind giving > it the space, I'd recommend a Panasonic SA-XR55 receiver. Isn't it supposed to run hot though? There may be problems putting it into a confined space with little or no ventilation. -- Mark Lanctot Mark Lanctot's Profile: http://forums.slimdevices.com/member.php?userid=2071 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
TimothyB;186332 Wrote: > I'm looking to power two pairs of speakers in my kitchen ceiling. Maybe > a pair of these amps would do the trick. Alternatively, if you can stump up to about $200, and don't mind giving it the space, I'd recommend a Panasonic SA-XR55 receiver. My experience of the T-amp, and reading about its technology, lead me to it. Digital all the way to the speaker output, no use of transistor amplification at all... I got one on Ebay for $160, and its performance is pretty stellar, though the jury is still out for me on its overall tonal balance. Is it a bit "cold", or am I just used to an overly warm and fuzzy amp? Put it this way - my favorite CDs are now all being ripped to FLAC, because the limitations of my 200kbps mp3s are very obvious in a blind test. I haven't tested 320kbps mp3s though. I'm using the TA-10 in the kitchen, and I think it's a great amp, but the Panasonic is better, drives multiple speakers, and is still pretty inexpensive (less than 2 TA-10.1s anyway). -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Is there a place to get one of these for $30? On Amazon, I saw a battery powered portable amp for about $32, but then I'd need to buy an AC adaptor? I'm looking to power two pairs of speakers in my kitchen ceiling. Maybe a pair of these amps would do the trick. -- Timothy -- TimothyB TimothyB's Profile: http://forums.slimdevices.com/member.php?userid=4868 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
I had my ELAs driven by the T amp for a few weeks. It wasn't too bad actually but I never played at loud volumes. -- gusi gusi's Profile: http://forums.slimdevices.com/member.php?userid=3801 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
So, the wife was out and the baby asleep last night, and I got a chance to do a more extended listen. Each amp swap was a few minutes of messing around with cables, so it was less than ideal. All my impressions were long gone from my short-term memory by the time I got to listen to the other amp. I was comparing: Creek 4330 amp vs. Trends Audio TA-10.1 Using an Arcam 7se CD player and Epos ES-12 speakers. I don't have any lossless encodings on the Squeezebox. Perhaps I should have done that for this forum :). I mostly listened to Elliot Smith, from Either/Or. As said before, the speakers are probably a bit too much of an effort for the poor little amp. To give it a chance I was only about 6-8ft away from the speakers. I was playing about 2 full songs with each amp before switching, because of the hassle factor, and I couldn't form a coherent conclusion. The T-amp was definitely more bright, sounded a clearer, but I alternately felt each was doing a better job than the other. A few times when I switched the Creek back on I thought it sounded relatively dull and muddy, but then I'd change my mind. In the end, I found a short passage to focus my attention on, and really listened to some details. Then, the verdict was hands down to the T-amp. I was clearly hearing and enjoying some background instrument details which were much less distinct and clear on the Creek. The T-amp just had better resolution of the the sound. I don't couldn't reproduce my impression before of the bass being indistinct either. I adjusted the output bias before listening, and it was off (~5mV and 2mV - doesn't sound much?). Perhaps that had an effect? Seems unlikely. I'd criticise the t-amp as being a bit over-bright in my setup - a little more wearing to listen to than it should be. My hearing is very sensitve to volume, particularly at the high end. Also, at times I was completely undecided, so it was quite a close thing. All the same, I think the fact that it was close, and ultimately I decided I heard more and enjoyed the music from the TA-10.1 better, is remarkable for an amp that cost 1/8 of the Creek. A miracle after all. I didn't have the SA-T-amp on hand to try that, and anyway, I was fed up with all the switching by the end. I'd love to do a blind test. Now the poor TA-10.1 is back in the kitchen facing the indignity of pushing the really muddy Optimus speakers, until and unless I replace them. -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
adamslim;184080 Wrote: > but don't expect miracles Depending on what I decide after a proper listen, I was probably suckered in by 'reviews like this' (http://www.6moons.com/audioreviews/trends/ta10.html): "this $100 amp sounds better [snip] than the $10K+ single-ended triode pre and power amp combo...". These reviews sneak into your consciousness even if you're skeptical, as I tend to be since my first listening session in a hifi shop when I tried out some magazine's award winners and they were the worst equipment I heard that day. I used to use a NAD amp (3020B) with output level LEDs, and I remember at normal listening I rarely lit the 1W LED, and had annoy the housemates to light the 5W light. No idea how accurate they were, and no doubt they weren't reflecting peak output, but that always gave me the impression that <5 Watts is all I typically used. Funny how my amp purchase has progressed :). I wanted to use the SB in the kitchen, so thought I'd get a SI-T-amp ($30)... Then looking for a power supply I ended up buying the TA-10.1 ($130)... Now having read about D and T-amps, I'm intrigued by the possibility of removing a step with the "digital amplifiers" - i.e. with the t-amp the SB converts digital to analog, the t-amp converts analog to an effectively digital bitstream, and converts that bitstream to an amplified analog output. But the "digital amps", like Panasonic's SA-XR line, convert the digital input to the bitstream all in the digital realm, and then convert that to the amplified analog output in one step. In principal, that's removing a lot of potential for distortion, and -some- people rave about them. I may have to stump up the $200 to try -that- out now, to see if I like it better than the Creek, or at least think it's worthwhile for the kitchen. Like you say - can't expect miracles, but it is genuinely new(ish) technology and it's not impossible that it represents a quantum leap, even if the Panasonic machines are covered in audiophile red flags. I may buy one from a major shop for curiosity and return it if I don't like it. Trouble with that is, with a 7.1 receiver in my living room, I might start thinking I need more than 2 speakers... Argh! :) -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
I have a T-amp in my computer system and use it for very casual listening. It's fine (i.e. surprisingly good) at low power but can't drive speakers properly - you'd need 90++ dB/W speakers to get sensible levels, IMO. In general I'd say the T-amps are a true hi-fi bargain in that they offer decent fidelity for a near-zero price, but don't expect miracles, especially at real listening levels. A proper amp like a Creek, at ten times the price, *is* going to be better. Adam -- adamslim SB3 into Derek Shek d2, Shanling CDT-100, Rotel RT-990BX, Esoteric Audio Research 859, Living Voice Auditorium IIs, Nordost and Anti-cables http://www.last.fm/user/AdamSlim/ adamslim's Profile: http://forums.slimdevices.com/member.php?userid=7355 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
You really need some efficient speakers with those amps, or they will sound 'underwhelming' :) Some names that come to mind are LothX, Omega, Zu, Totem, older Klipsch, and of course all the single driver DIY speakers (fostex, hemptone, visaton, lowther or anything cheap on ebay with a whizzer cone). Lots of cheap stuff on audiogon as well, including subs which will probably be needed to fill out the lower Hz of any of those speakers. I realize you're not trying to replace your main setup, but wanted to offer suggestions anyway. I've found magnet wire/Anti-cables fit as speaker wire in the spring clips, but also has a tendency to roll off the bass even further. It may be worth trying some smaller diameter stranded wires like zip cord. Thanks for adding your thoughts. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
Well, I got the TA-10.1 T-amp, and tried a quick test with my best speakers (EPOS ES-12) - unfortunately they are very hard work for the T-amp. They're not particularly sensitive, and I read something about them being demanding of an amp and later versions (M12, M12.2) were more forgiving. It was a very quick test, and I couldn't draw any conclusion. It is very different from my Creek 4330. The first thing that struck me was the bass, and not in a good way, even though I'm not a bass-fiend. I didn't expect strength, but the clarity seemed to be absent. With the Creek + Epos, on hearing a bass drum the image of the striker (terminology?) hitting the skin clearly forms in my head. With the T-amp there was just a muffled low tone which could have been anything - not much quieter, just much less distinct. Take this with a pinch of salt though - it was a very brief test. The kind of forwardness of the mid and upper end was striking. I need to listen much more to form an opinion. It took me aback through Creek-attuned ears, but then I started to appreciate the detail I was hearing. At the weekend I may get time to sit there and give it a good listen. Until then it's doing duty in the kitchen driving some "Optimus" speakers that sound like they're operating in a bucket of water. At least when listening to net radio, the newsreaders' voices sound "mellow" ;). There's a long and awkward delay when I switch the cables, and any hope of a blind test is out the window. The only people I could call on for help would be laughing and rolling their eyes too much. I could actually compare it to an original Sonic Impact T-amp, because I ordered that for my purpose originally, then started looking for a power supply, and discovered the TA-10.1, and decided to stump up the big bucks ($130) for that. The only problem is I couldn't fit my speaker cables into the SI-T-amp. Shame if it's not up to the Epos - I was contemplating buying some used M12s. Perhaps I could buy another TA-10.1 and bi-amp them. That might help :). -- jimmyfergus jimmyfergus's Profile: http://forums.slimdevices.com/member.php?userid=4323 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
I have a Super-T, and it really offers incredibly detailed reproduction for the cash. My advice would be to put it into some speakers that have decent low-end reproduction. I'm running mine into a pair of little Quad L-ite speakers, and while there is lots of detail and a surprisingly good stereo soundstage, there is a certain harshness at around the 1.5k mark. Going into some older, more worn in speakers this harshness isn't present, and connecting the little Quads to an old NAD amp also eliminates this little frequency hump, so I'm guessing it's to do with the combination. So that is something to think about - but otherwise I think these are very impressive little amps for the money and a perfect match for the SB3. -- Codmate Codmate's Profile: http://forums.slimdevices.com/member.php?userid=7154 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audio Trends TA-10 Amp (t-amp)
jimmyfergus;183699 Wrote: > > The TA-10.1 is a much better put together unit, with better components > and power supply, for the heady price of $120 or so. > While I don't doubt the Trends uses better parts and construction, I found it interesting that I preferred the sound of my original $30 T-amp to the superT. Although in fairness, the volume pot on the original was noisy, and the speakers they were powering didn't play low enough to show <100Hz differences between the two. I hesitate to speculate, but one difference that sticks out is the size size of the board (the original has more SMD components). I'd be curious to hear what you think when it arrives. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=33112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
