Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
tyler_durden;235161 Wrote: > But where is the documentation that tells anyone that the capability is > there? > > What else are they hiding in there? > > How often does it turn on the built in mic and night vision camera so > they can monitor everything going on in my home? > > TD :-) I'm with you, Tyler... but I couldn't get it to work anyway... anyone out there actually had success with the level check function? -- westernboy "Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein westernboy's Profile: http://forums.slimdevices.com/member.php?userid=12768 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
But where is the documentation that tells anyone that the capability is there? What else are they hiding in there? How often does it turn on the built in mic and night vision camera so they can monitor everything going on in my home? TD -- tyler_durden tyler_durden's Profile: http://forums.slimdevices.com/member.php?userid=2701 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Hear, hear. Thanks for sharing your story - we all easily forget this basic thing when we *think* we are doing effective cross-listening to compare stuff. It is hard to get that aspect right, and heck yeah, the slightly louder output will win every listening test hands down. -- pablolie pablolie's Profile: http://forums.slimdevices.com/member.php?userid=3816 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
seanadams;229040 Wrote: > Yes, level matching is absolutely critical. FYI there is a way to test > analog levels that is much easier and more accurate than using pink > noise and an SPL meter. > > 1. disconnect sources from amp > 2. play SB3's built in sine (press 3 on startup screen) > 3. connect AC voltmeter to one of the RCA connectors > > Then just tune the gain on the DAC until it matches SB3's reading. Wow, awesome trick. Why didn't I think about it? :-) I had no idea step (2) was available. Some smart guys designed the Squeezebox. :-) That's why I love it. -- pablolie pablolie's Profile: http://forums.slimdevices.com/member.php?userid=3816 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Those who read my original post may be interested to know that I have found an affordable external DAC that improves on the sound produced by the analog outs of the SB3. It is a Beresford TC-7510 (see http://www.homehifi.co.uk/main/main.html) modified from stock with the designer's "Class A" output stage. The unmodified unit, after burn-in, sounded identical (to me) to the SB3, and therefore the CI VDA-1 - which is to say, very good. The Class A mod, however, (an extra cost option) provided better defined bass and more transparency to the high frequencies. And, yes, all listening was done after careful level matching... :-) For a total of AUD350, I'm very happy... although I still lust after a Transporter. -- westernboy "Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein westernboy's Profile: http://forums.slimdevices.com/member.php?userid=12768 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
The "problem" is that when two systems have different frequency response there's no unique way to level their volumes. You could do so using a sine wave at some particular frequency (as Sean suggested) or with the SPL of broad-spectrum noise - but those are just two of an infinite number of different possibilities. This isn't a problem if you are only trying to determine if two things actually differ. If they don't, all volume-leveling techniques are equivalent, so just pick the easiest. But if they really are different and you want to determine which you prefer it's much more tricky. In that case I would think something like the SPL of pink noise is probably better than a single frequency b(ecause it's an average and therefore more robust to narrow changes in frequency response) but there's no one right answer. It's a question about psychoacoustics, not acoustics. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Yes, level matching is absolutely critical. FYI there is a way to test analog levels that is much easier and more accurate than using pink noise and an SPL meter. 1. disconnect sources from amp 2. play SB3's built in sine (press 3 on startup screen) 3. connect AC voltmeter to one of the RCA connectors Then just tune the gain on the DAC until it matches SB3's reading. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Thanks, Phil, for your response. I'll have give the whole thing some more thought and experimentation. I've also been reading the "First shot at using Inguz" thread which is a real eye-opener. -- westernboy "Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein westernboy's Profile: http://forums.slimdevices.com/member.php?userid=12768 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Well pink noise isn't music...so I'm not sure how one would use it other than to measure frequency response. I suppose the point is that once you have designed your correction curve and implemented the filters then you could use pink noise to measure the corrected in-room frequency response. That's fine and doesn't require any gain matching. You can still create valid before/after response measurements at different overall gains. I thought the issue was about comparing music with/without RC (after you've got your correction curve built)? My point was that the music will inevitably sound louder when either flat or corrected, depending on the correction that is being applied. Usually RC will cut the bass quite deeply which makes the listener think the volume has been lowered (which it has - at their ear!) so to get back the same feeling of energy in the music you have to up the overall gain a bit to compensate. So, doing a A/B comparison is quite tough on the old brain. It really is just like comparing two loudspeakers with different sensitivities and frequency and dynamic responses. Everything changes - dynamics, timbres, stereo imaging...the lot!. For me the only way to evaluate RC and its curves is long term listening. Eventually I find that if I turn off the RC I really don't like the sound. Because of my setup, I have to bypass RC to use headphones. Occasionally I forget to turn it back on. Then I play the SB through speakers and wonder why it sounds "all bass and treble", harsh in the midrange with the image shifted to one side and a slightly "phasey" sound. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... ...SB3+TACT+Altmann+MF DACXV3/Linn tri-amped Aktiv 5.1 system and some very expensive cables ;o) Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Phil Leigh;228830 Wrote: > FWIW I don't think you can evaluate RC in the same way. It's doing such > a lot to the signal that you can't balance gain because by definition > it's changing the frequency response quite significantly. Hey Phil, that's an interesting point for me, as I plan on using the Inguz RC once I have a music server that's capable of running it. I thought pink noise covered the whole audio spectrum, so wouldn't that still be a valid basis for comparison? Although, that raises the question of how to switch between uncorrected and corrected music - I imagine if I had experience with the Inguz plugin I would know how that's done... -- westernboy "Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein westernboy's Profile: http://forums.slimdevices.com/member.php?userid=12768 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
That's very true, and I am also being cautious about that while evaluating the effects of the Inguz plugin, since depending on teh level of correction, the gain will change. -- Chinanico CEC TL51X / SB3 > Audiomat Maestro > Jeff Rowland Concentra 2 > System Audio SA2K Chinanico's Profile: http://forums.slimdevices.com/member.php?userid=12794 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Level matching - a cautionary tale
Very interesting. Thanks for this. -- Rick B. Rick B.'s Profile: http://forums.slimdevices.com/member.php?userid=8973 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Level matching - a cautionary tale
Although the following findings will not be news to some, or perhaps most, of the members of this forum, I felt I should share the learning experience I had this week: I've have had an SB3 for about 6 weeks, and continue to enjoy rediscovering my music collection. As an audiophile (note the lower case 'a'), I've been looking at ways to achieve a sound quality similar to the Transporter at a price that's more in line with my current financial situation. An outboard DAC seemed an appropriate path - so when a used Channel Islands VDA-1 / VAC-1 pair (see http://www.stereotimes.com/acc010603.shtml for one of many reviews) appeared recently on eBay, complete with some ModWright-like improvements, I bought them. For those who are interested, they cost me roughly 1.2 times the price of the SB3. I added these to my system early this week, keeping the SB3 analog out connection to one input on my amp, and connecting the output of the DAC to another amp input. Comparing the two DACs was then just a matter of a button press on the amp remote. I was immediately impressed - the CI gear provided a sound that was noticeably more enjoyable to listen to. In case I was just hearing what I wanted to hear, I asked my dear wife to listen without telling her which was which. She easily identified the CI DAC every time. A number of glowing adjectives were exchanged in describing the sound but, in the end, we agreed on the description "more alive". Sometime later that day I started getting the uneasy feeling that I'd forgotten something - and then it came to me... were the levels of the two outputs matched? I'd read about the importance of this, when comparing hifi gear, in many places (including this forum) and thought it was something I fully appreciated - but I was wrong. Setting up my trusty RadioShack sound level meter and some pink noise on the SB3 I soon discovered that the output from the CI DAC was 2dB above that of the SB3 DAC. Making them the same was a bit of a challenge, as the output of the SB3 was already maxxed, but once it was done I had to swallow my pride and admit that the sound of the two was virtually identical. There may have been slightly more 'sparkle' to high frequencies via the CI but I could just as easily have imagined that. I'm certain enough of the results that I've put the CI combo up for sale again. Apart from the reminder of my own fallibility, this exercise has helped me internalise how vital level matching is in these situations. I have also gained a new appreciation for the remarkable job SD have done to provide a quality DAC in their entry-level product. To get a real improvement in fidelity I may have to start saving for that Transporter... -- westernboy "Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein westernboy's Profile: http://forums.slimdevices.com/member.php?userid=12768 View this thread: http://forums.slimdevices.com/showthread.php?t=38553 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
