USB audio input

[upaya]

Hello All,

I am contemplating my second AMP4 build and am looking for any advice regarding adapting the designs for USB input.

my primary audio source is a laptop with a bog standard soundcard. with USB input i am trying to bypass the soundcard and losses due to digital - analogue - digital conversions.

does anyone here have experience of USB inputs on 41hz' amps and if it might be possible without too many complexities?

Thanks

[wadoka]

Hi,

Just because they are called class d amps doesnt mean they are digital. They are still analogue amps, they work by switching the fets on and off very quickly.
You will still need some form of D-A conversion going on somewhere. DIY usb soundcards are floating about on the net, perhaps use one of these

[krilli]

Yep, and there's a good chance that you can get better quality with a DIY USB dac, even though the reason isn't the same as you'd intended

... here's a link to a nice and interesting thread about this: http://41hz.com/Forums/topic.asp?TOP...hTerms=diy,dac

[tobias_svensk]

Well the cheapest I guess is the BantamDAC, you build it for $25-50 or so:
http://www.diyforums.org/BantamDAC/B...ACoverview.php
http://www.beezar.com

Or the USB-DAC from TwistedPearAudio ($75 assembled):
http://www.twistedpearaudio.com/digital/usb.aspx

Or buy a PCB from Damian (like I did):
http://www.unisonus.com/old/projects/pcm2702.html
http://www.ettnet.se/~tobias/diy/usbdac/usbdac1.jpg (that's my build, works great)

/Tobias

[upaya]

Thanks guys for your replies. They led to a 5 hour spin across the internet in search of the best way to bypass the musical impurities added by a rubbish soundcard.

if i continue with previous plans to build an AMP4 i will purchase either the USB-DAC from TwistedPearAudio, or the Trends Audio USB DAC UD-10.

however, because i got a little side-tracked i stumbled upon ICEpower Amps which operate with the same high efficiency as T-amp's but with potentially better compatibility with more speakers... particularly my Fostex FE166E's.

I wouldn't want to cause a stir as i think 41hz' amps are brilliant but it looks as though i am heading to the dark side with purchasing a complete amp (it'll take longer to save up though).. possibly these ones here http://www.audio-magus.com/product_p/ia55i.htm or http://arhifi.com/shop/default.asp or http://www.murano-audio.com/product.php

Thanks again for your help good people..

[V-bro]

I would be careful, I'm afraid some of them won't even sound half as good as an AMP6....

------X-max. can be several meters on any driver, too bad it can be done only once...------

[upaya]

Hi V-bro!

i've just been reading your friendly chat with CNX over on the DIY forum. After reading the first dispute on that topic it was interesting to see the second unravel at the invitation for constructive criticism. I have read your posts in various places over the past year or two and have come to greatly respect your opinion on amplifiers.

The nature of these audio forums is subjective, loaded and sometimes becomes a minefield of commercial bias, It all becomes a little difficult to navigate sometimes. what i am getting to is that i am struggling to pick the ideal board for a low energy building project i am a part of. I was hoping you might have some more constructive criticism to send in my direction.

With efficiency as the main priority and audio quality following closely behind... what amplifiers or boards would you recommend? I have a pair of 8 ohm Fostex FE16's if that makes a difference to the recommendation. what would be your own ideal music system?

Thanks

[V-bro]

Hi Upaya,

yes I really didn't mean to let it end up in such an embarassing clash. His approach is just different. That's why I would never buy his amp. Even though his amp is better than many commercial designs. When you're building a thousand amps and you can save 2Eur. on a part it ends up as 2000Eur. in your pocket. I understand that, my approach however is more from an idealistic point of view. The best designs have been made by hardly calculating a thing, mainly using one's gut feeling. In practise this approach proves to give much more durable results. And with Tripath being bankrupt who knows how long your amp needs to last?

What's the reason you need the sytem to consume little energy? Of course most can be gained here by using high efficiency speakers. I couldn't find specs for those FE166E drivers, do you happen to have them?

My own ideal music system in terms of best sound at home sitting in my couch? Up to now I've never enjoyed music more than from my bi-amped dual Truepath driven OB speakers with Quad ESL-57 treble panels and JBL 2220A 15" woofers. I've never heard something sound so lively and uncoloured...

------X-max. can be several meters on any driver, too bad it can be done only once...------