24 bit audio over USB

Heh... chick drink :-)

Making people wade through twenty pages of irrelevent material just to get to your two clever lines is obnoxious.

You should. Because basically there are only a couple USB chipsets out there, which everybody is using. Pick the USB chipset that you see in a typical product, THEN use their driver. In all probability, the driver is going to be provided by the chip manufacturer anyway and they should have full driver source available on their web site.

For Firewire, most folks are using the TI GPLynx2 chipset. For USB 1.0, the popular ones were the TI USB3200 and TAS1020B. I don't know who is making the USB 2.0 audio chipset of highest popularity today.

--scott

--
"C\'est un Nagra.  C\'est suisse, et tres, tres precis."

maybe

It may come to that. I'm finding it tricky to locate much info on the subject.

For 24 bit ? I recall speaking to TI and they said their stuff was only designed for

16.

today.

If anyone *does* know !

Graham

All modern computer equipment is designed for 8 or 16 or 32 bit. It is the firmware/software that decides how to handle 24 bit data in the conventional 16-bit world.

Clearly the people making the equipment know. My own employer may be the primary vendor for all I know.

I personally have a sound card with optical digital inputs and outputs and leave the A/D and D/A to my audio gear. You can find USB sound cards with digital audio inputs and outputs (both optical type SPDIF and RCA type TOSLINK).

For A/D and D/A I'm using a Sony minidisc deck. If you hit record when there isn't a MD in the deck, it does both A/D and D/A conversion. The input button lets you switch between the analog and digital inputs. Of course, you can buy external A/D and D/A converters, or use the ones that exist on many modern amp/receiver/surround sound systems.

Jeff

--
    "They that can give up essential liberty to obtain a
     little temporary safety deserve neither liberty nor
     safety"
- B. Franklin, Bartlett\'s Familiar Quotations (1919)

A dedicated USB audio chipset *does* make the distinction though.

Grahan

I'm effectivly *designing* a sound card - not in the market to buy one.

Graham

I know, but I fail to see the point when there are many affordable USB sound cards with digital audio inputs and outputs. Plus, I prefer optical digital connections to keep the electrically noisy PC completely electrically isolated from my audio equipment.

If I were you I'd concentrate on the high end A/D and D/A parts of the circuit and use an existing USB sound card with digital inputs and outputs to drive it.

Jeff

--
    "They that can give up essential liberty to obtain a
     little temporary safety deserve neither liberty nor
     safety"
- B. Franklin, Bartlett\'s Familiar Quotations (1919)

Pooh Bear skrev:

how about getting one of these for inspiration?:

-Lasse

I'm not making one of those am I ?

Quite sensible.

That won't fit my target market. Also is a clumsy implementation.

I do wish ppl wouldn't keep saying don't bother, use something else btw. I don't want to give away my 'secrets' but all I want is a USB audio interface to incorporate in something else.

Graham

Pooh Bear spake thus:

[snip]

Amazing. Just f****ng amazing.

34 replies to your question, by my count on my ISP's view of the group, and *not one useful answer to your question*. (Including my two, make that three, posts, I'm sorry to say.) Lots of people saying "f*ck that, won't work", or "why bother?" and other useful tidbits.

Ain't Usenet wonderful?

--
Any system of knowledge that is capable of listing films in order
of use of the word "fuck" is incapable of writing a good summary
and analysis of the Philippine-American War. And vice-versa.
This is an inviolable rule.

- Matthew White, referring to Wikipedia on his WikiWatch site
(http://users.erols.com/mwhite28/wikiwoo.htm)

don't

It sounds to me like that's exactly what people are suggesting - if a "USB sound card" isn't a "USB audio interface", I don't konw what is.

Or are you looking for a one-chip thing, to embed? If so, you should know by now that you should have already said so.

Good Luck! Rich

A lot of the answers looked to me like "Why design and build, when you can buy cheaper?"

If that's not good enough, then we need a more comprehensive system specification.

Thanks, Rich

It's a crowded market. I don't know what Graham is trying to prove.

Ok. I need an *embedded* USB audio interface. To repeat ; a chip or chipset.

Is that OK ?

Graham

I'm not trying to prove *anything* ! I want a solution for a product. You can buy analogue audio mixers these days with USB and Firewire interfaces for example. This is kind of thing I'm talking about.

Graham

Pint? I thought you used liters? ;-)

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

can

I did some searching and found this from M-Audio:

The Codec used in this unit is the following:

Which implies that some other chip is still needed to format the data and transfer it over USB.

Meindert