Re: [SlimDevices: Touch] So, can we now have apodising please?
andyg;539956 Wrote: I'll tell you right now Logitech won't do this, so use your Meridian receiver or work on an open-source solution with sox. My thanks for all of the replies chaps. I guess the above on is most relevant, assuming that the tag is correct that he is an employee. Still, it was an idea. John My extended thanks for your more lengthy explanation. I have heard the Meridian solution, certainly did work. My understanding is that there's is completed as part of an upsampling process. One point that I was a little confused about was your suggestion that the filter should be matched to the DAC. Makes logical sense to me. However, Meridian seems to advocate that the apodizing is completed as close to source as possible, and certainly can't control all of the DACs that eventually do the actual digital to analogue conversion, implying that whatever they've done would work with a more generic type of DAC. One other thought I had last night was regarding the suggestion of close as possible to the digital source. Maybe another route would be to get something like Foobar2000 to upsample files and resave them post upsampling with the filter applied. It would clearly result in larger files, but as I've got plenty of disk space, I don't really see it as a massive problem. If it could be done to the files at source, it wouldn't matter what hardware it was played on, just aslong as the hardware could deal with CD files saved at 16/88.2. Let me go investigate that a bit more. -- Mr_Sukebe SB Touch, Meridian 568.2, Bel Canto Evo2i, Impulse Ta'us, Coherent system, audio-technica and Zanash cables, Stillpoints Mr_Sukebe's Profile: http://forums.slimdevices.com/member.php?userid=10609 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
[SlimDevices: Touch] So, can we now have apodising please?
I know that there's been a number of requests for a variety of additions to the Touch. Here's mine, which actually has a business case with it. Meridian has introduced apodising in some of it's newer kit. As I understand it, it's a clever algorithm which supposedly makes digital music sound a little more analogue. I would absolutely love it if this could be purchased from Meridian and introduced into the SB range (preferably for local processing within the Touch, though I don't know if it has the horsepower for that). I do believe that DCS and at least one other high end audio manufacturer (maybe Ayre) licensed it for some of their gear, implying that Meridian are willing to sell it on to other groups. Now before you say but that won't be cheap, yes, I appreciate that, and I'm not asking to be given it (though that would be nice). I'm guessing that Logitech have large user base, some of whom would be very interested in using apodising. So how about simply selling it as an add on for those genuinely interested. I've no idea how much Meridian would want, but I'd definitely be willing to pay say $50 for it. And the benefits: - As a user I'd get a better sounding SB - The SB range are already moving towards a more niche market (after all, most competitors can also stream video). So why not add a serious USP by offering apodising too - Given the potential purchasing power of Logitech, I'm hoping that the cost from Meridian wouldn't be that much on a unit basis. Along the way, I'd assume that Logitech would add something of a markup, thus adding to their bottom line. So, how about it Logitech? -- Mr_Sukebe SB Touch, Meridian 568.2, Bel Canto Evo2i, Impulse Ta'us, Coherent system, audio-technica and Zanash cables, Stillpoints Mr_Sukebe's Profile: http://forums.slimdevices.com/member.php?userid=10609 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
Why can't you just use the function in your receiver to do this processing? -- andyg andyg's Profile: http://forums.slimdevices.com/member.php?userid=3292 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
andyg;539915 Wrote: Why can't you just use the function in your receiver to do this processing? Or use sox plugged into SqueezeCenter - already discussed at length in http://forums.slimdevices.com/showthread.php?t=69145 Regards, Kim -- krochat -- iZotope SRC (96kHz offline upsampler) - Touch - TacT RCS 2.2X - Convolver PC (w/Acourate filter)- Apogee Big Ben - (TacT S2150 - Vandersteen 3a Signature + TacT S2150 - TacT W210) krochat's Profile: http://forums.slimdevices.com/member.php?userid=6579 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
Yes SOX can do it, cpu demand is probably above the Touch otherwise SOX would be on it already as it is the transcoding tool. Note that the built in server on Touch don't do transcoding due to cpu demand. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J and assorted amps SiriuS, Classe'Primare and Dynadio speakers (including a pair of Contour 4 ) Bedroom/Office: Boom Kitchen: SB3 + powered Fostex PM0.4 Miscellaneous use: Radio (with battery) I use a Controller various ir-remotes and a Eee-PC with squeezeplay to control this Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
krochat;539919 Wrote: Or use sox plugged into SqueezeCenter - already discussed at length in http://forums.slimdevices.com/showthread.php?t=69145 Regards, Kim I've read the thread about it, and don't believe that they have introduced apodising. From what I could see, they're tried to emulate it, and as the thread has petered out, I assume they've given up. What I'm suggesting is that Logitech work with Meridian to allow interested users to buy single user licenses for their algorithm, hopefully giving us a cheap working solution, whilst still making money for both groups. -- Mr_Sukebe SB Touch, Meridian 568.2, Bel Canto Evo2i, Impulse Ta'us, Coherent system, audio-technica and Zanash cables, Stillpoints Mr_Sukebe's Profile: http://forums.slimdevices.com/member.php?userid=10609 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
I love Meridian gear. But Meridian just dont do cheap. I dont think theyd licence this for something Logitech would consider reasonable -- markn markn's Profile: http://forums.slimdevices.com/member.php?userid=14846 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
markn;539947 Wrote: I love Meridian gear. But Meridian just dont do cheap. I dont think theyd licence this for something Logitech would consider reasonable I understand what you're saying, but just consider the options here, i.e. 1. Meridian themselves use it and license it to DCS and Ayre and get say $200 per unit from DCS and Ayre (I've no idea how much they really get, but just as an example). Maybe they make $200,000 from it. 2. Meridian license it in partnership with Logitech and Logitech sell it as an add on for the SB and 10,000 enthusiasts buy it resulting in Meridian getting say $20 each. That would double the income for Meridian. In addition, it would help advertise both Logitech and Meridian to a bigger audience. If Logitech could get Meridian to agree to a payment for every sale of the upgrade to users, there would be no upfront capital costs, only the development costs to ensure that it works. -- Mr_Sukebe SB Touch, Meridian 568.2, Bel Canto Evo2i, Impulse Ta'us, Coherent system, audio-technica and Zanash cables, Stillpoints Mr_Sukebe's Profile: http://forums.slimdevices.com/member.php?userid=10609 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
With those kind of numbers it would probably be cheaper to donate to the SoX project and have them build it opensource. -- pounce pounce's Profile: http://forums.slimdevices.com/member.php?userid=12645 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
I'll tell you right now Logitech won't do this, so use your Meridian receiver or work on an open-source solution with sox. -- andyg andyg's Profile: http://forums.slimdevices.com/member.php?userid=3292 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
Meridian also own Sooloos nowdays thats their own streaming device. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J and assorted amps SiriuS, Classe'Primare and Dynadio speakers (including a pair of Contour 4 ) Bedroom/Office: Boom Kitchen: SB3 + powered Fostex PM0.4 Miscellaneous use: Radio (with battery) I use a Controller various ir-remotes and a Eee-PC with squeezeplay to control this Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
Ok what I am trying to figure out is how Meridian is able to eliminate pre-ringing? Pre-ringing occurs at the DA stage and happens because of the filter mechanism applied to eliminate aliasing. How is an algorithm that occurs prior to the DA stage going to fix something that happens during DA? Note many DACs include other filters besides a brickwall filter (type that cause pre-ringing) so this solution is both not new or unique. -- m1abrams m1abrams's Profile: http://forums.slimdevices.com/member.php?userid=850 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] So, can we now have apodising please?
Many people these days are getting apodizing and minimum phase filters confused. They are very different things. Neither of these requires any special algorithm, they can both be implemented in standard FIR filters. Nobody has intellectual property on either concept. Certain companies may claim IP for a specific implementation, but that does not mean they have claim to the basic concept which can be implemented by anybody. If you already have an FIR filter mechanism adding an apodizing or minimum phase filter (or both) is trivial. Both apodizing and MP filters are compromises, you are trading off one aspect for another, the trick is to come up with exactly where you want to be in the compromise space, and THAT can only be done by listening. So on to implementing a custom filter in the Touch. Currently there is no way to replace the filter in the Touch with another filter. The chip MAY have a way to implement an external filter, but that definitely has not been implemented in the hardware. I don't think its possible to completely turn off the inbuilt filter and do it entirely in the CPU. For some reason when DAC chip makers disable the internal filter they use different pins for the inputs. So you COULD do it, but the hardware would have to be designed for it. I'll have to check on the specific DAC chip and see. You COULD implement an apodizing or MP filter in software with a 2X oversampling which converts 44.1 to 88.2, but then you are cascading two filters, the one in the software and the one in the hardware. This is fraught with peril. Its likely to result is something you do not expect. Even if you design the software filter for a specific DAC chip's filter, there is no guarantee the combination can get close to what you want in the first place if you were designing the hardware filter from scratch. Designing a software filter such that when it is cascaded with the hardware filer will produce the desired filter function is NOT trivial. In order to do this correctly you need the specific details of the filter already in the DAC chip. Nobody puts this in their spec sheets. So you will have to run some tests to try and figure out what it is. And just to make it more fun, most DAC chips already have cascaded filters, which is going to make the task MUCH more difficult. Of course you can try 5000 filters and see what sounds the best. And even that is a VERY tiny slice of the possible space. You might get lucky, but probably not. Less someone gets the wrong idea, I AM definitely in favor of custom DAC filters, I don't think ANY chip maker has correctly implemented their digital filters. I implement my own in my own DAC designs, BUT doing that in the Touch is going to be extremely difficult. The best bet is to just enjoy the Touch as is. John S. -- JohnSwenson JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=77869 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
