USB DAC

Wayne1 · « **on:** 6 Jan 2007, 05:24 pm »

There has been a lot of interest in computer audio

The modded Squeeze Box is one of the best sources available for this.

There are some folks who don't want to "deal" with hooking up routers and setting up networks, etc.

For them it makes more sense to use a USB DAC.

Mike From Tweek Geek sent me a couple of product to look over to see if I would be interested in modding them

One of them is the Trends Audio UD-10 USB Converter. This small box can connect to you computer and output audio form it's own internals DAC. The analog output is through an 1/8" stereo mini-plug. They supply a dual RCA female to 1/8" stereo male adapter so the unit can be connected to your stereo as well as driving headphones directly.

The back panel of the unit has FOUR different digital outputs. You can use the UD-10 to to connect to an external DAC through optical, coaxial, both RCA and BNC, and AES.

The unit will operate from the USB derived 5 volts DC but it does sound much better with an external power supply.

It just so happens that the DC connector is the same as a Squeeze Box requires. A good upgrade would be to use one of the ELPAC 5 volt PS with it.

I am trying it out playing into the EE BBA into my amp and speakers. It doesn't sound bad at all.

I will be looking at some mods for it later on. I can see some fairly inexpensive upgrades right away.

The best thing about it is the cost of the UD-10 should be under $90.00.

I think this would be a great piece of gear for an office system driving powered speakers or headphones.

launche · « **Reply #1 on:** 6 Jan 2007, 06:31 pm »

So thus far from your listening sessions is this unit not suitable for the main rig used as a DAC for PC audio? What about it's use just a pass through inbetween a DAC and the PC, basically just accepting the USB input and sending the signal on to another DAC like the HagUSB device does.

Thanks

Wayne1 · « **Reply #2 on:** 6 Jan 2007, 07:04 pm »

I have only had it in system for less than a day.

In stock form, I do not consider it anywhere near the modded Squeeze Box.

I have a couple of changes to make to it and then we will see. It will take many hours to be sure.

I do not use or have on hand any external DACs to test out how it sounds as an USB to SP/DIF interface.

At some point, in the coming months, I do hope to get together with some folks to test that ability out.

Wayne1 · « **Reply #3 on:** 6 Jan 2007, 11:42 pm »

I have changed out quite a few parts in the internal power supply, decoupling and audio signal output.

It is running into the Eastern Electric BBA and the sound with this combo is VERY nice.

It will need a few hundred hours for the mods to settle in (LOTS of Black Gates were involved) but initial impressions of the mods are very positive.

yo2tup · « **Reply #4 on:** 7 Jan 2007, 12:03 am »

very cool! since i got the analog mods on my sb3, my external dac has been collecting dust. i can move it to a computer system now with this unit

mgalusha · « **Reply #5 on:** 27 Feb 2007, 04:24 pm »

An update to this thread. I took possession of the modded version of this DAC on Sunday, Mike from Tweekgeek gave it to me in trade for repairing his Transporter. Unfortunately for Mike he didn't get to hear it as Wayne brought it over to return to Mike but I grabbed it.

I've got it running in my office feeding a pair of Swans M-200 powered speakers and am using foobar 0.9.4 and the ASIO4ALL ASIO driver powered by one of the modded ELAPC power supplies.

This is a very nice sounding little DAC. I'd been using a modified Stereo-Link USB DAC and while it was pretty good the little Trends UB-10 is much better. I can't say how the stock unit sounds but the modified piece is very good. I'm going to have to bring it back home and see how it stacks up to my SB2 and the Altmann Attraction DAC as well. At home I'll feed it power from the supply I use for my SB2, which is basically the same as the BOLDER Ultimate PS.

A very nice piece indeed. I think Mike from Tweekgeek is working with Wayne to offer these already modified but I don't know for certain.

Mike

chadh · « **Reply #6 on:** 27 Feb 2007, 04:37 pm »

I don't understand. Is this thing a DAC? Or is it just a USB-to-SPDIF converter? It seems to have a USB input and four different digital outs. How can you use it as a DAC?

Then again, it has a headphone jack, suggesting it has some sort of DAC in it.

I guess I'm just confused.

Chad

mgalusha · « **Reply #7 on:** 27 Feb 2007, 04:54 pm »

Hi Chad,

Yeah, I was a little confused at first as well. It uses a Burr-Brown PCM2704 USB DAC chip. This chip has a USB 1.1 interface with both S/PDIF and analog outputs, so the Trends UB-10 can drive headphones or powered speakers directly from the analog outputs and/or provide an S/PDIF output to run an external DAC from a PC source.

The one thing it won't do is accept an S/PDIF signal and convert it to analog, the only analog output is from a USB source, so it can't be used as a DAC from a "normal" digital source.

Mike

Wayne1 · « **Reply #8 on:** 27 Feb 2007, 05:16 pm »

The Trends UD-10 will output a line level from the headphone output on the "front" panel.

It comes with a 1/8" stereo mini-jack to dual RCA female adapter. You can hook it up direct from the UD-10 to an amp.

I would be very careful doing this, as the jack connection is a little loose. This can cause some really nice, full output noise if you move things around and the adapter loses the ground connection

The headphone output may be okay for driving a set of very efficient cans, but I wouldn't try to use a set of Sennheisers without a separate headphone amp.

mgalusha · « **Reply #9 on:** 27 Feb 2007, 05:58 pm »

Quote from: Wayne1 on 27 Feb 2007, 05:16 pm

I would be very careful doing this, as the jack connection is a little loose. This can cause some really nice, full output noise if you move things around and the adapter loses the ground connection

I'll vouch for that. Running into my powered speakers it's very easy to make them cut out if I move the DAC or cables. For my use I'm going to lose the RCA and BNC digital outs and install a pair of RCA jacks for analog out so this won't happen again. Dang, haven't even had it for 2 days and we're already talking surgery.

sunshinedawg · « **Reply #10 on:** 27 Feb 2007, 06:02 pm »

Quote from: mgalusha on 27 Feb 2007, 04:54 pm

Yeah, I was a little confused at first as well. It uses a Burr-Brown PCM2704 USB DAC chip. This chip has a USB 1.1 interface with both S/PDIF and analog outputs, so the Trends UB-10 can drive headphones or powered speakers directly from the analog outputs and/or provide an S/PDIF output to run an external DAC from a PC source.
Mike

Has anybody tried it yet just as an s/pdif output yet? I love my modded squeezebox but it can't do DSP very easily. I would be interested in using this to feed digital to my Bolder modded xr45.

Quote from: mgalusha on 27 Feb 2007, 04:54 pm

I'll vouch for that. Running into my powered speakers it's very easy to make them cut out if I move the DAC or cables. For my use I'm going to lose the RCA and BNC digital outs and install a pair of RCA jacks for analog out so this won't happen again. Dang, haven't even had it for 2 days and we're already talking surgery.

No! don't lose the digital outs!

Sean

mgalusha · « **Reply #11 on:** 27 Feb 2007, 06:08 pm »

Quote from: sunshinedawg on 27 Feb 2007, 06:02 pm

Has anybody tried it yet just as an s/pdif output yet? I love my modded squeezebox but it can't do DSP very easily. I would be interested in using this to feed digital to my Bolder modded xr45.

Hi Sean,

I'm going to try that this evening feeding the S/PDIF into the Altmann Attraction DAC. I'll let you know how it works.

Mike

sunshinedawg · « **Reply #12 on:** 27 Feb 2007, 06:14 pm »

Thanks Mike. I've been looking at picking up a used stock Edirol UA-5(for use a USB s/pdif onverter) on ebay, but keep on getting outbid

Can this unit take a digital input and then do some DSP on the PC and then output digital?

Sean

mgalusha · « **Reply #13 on:** 27 Feb 2007, 06:22 pm »

Quote from: sunshinedawg on 27 Feb 2007, 06:14 pm

Can this unit take a digital input and then do some DSP on the PC and then output digital?

Nope, the only digital in available is via the USB port, all the others are output only. If you have a way of getting the digital signal into the PC you should be able to send it out to the Trends. If the source is on the PC it should be possible to route the player output through the DSP and then to the Trends. I know foobar will do this.

Don't worry, I won't lose the S/PDIF interface until I've had a chance to try it with the Altmann. I may just drill a couple of holes in the front panel and keep the digital outputs. I was thinking about losing the digital because I could reuse the holes and it would look nicer but as it's going to sit on top of my PC where I can't see it this won't matter much.

chadh · « **Reply #14 on:** 27 Feb 2007, 07:05 pm »

Mike and Wayne,

Thanks for the explanation.

From a marketing point of view, this seems like a weird arrangement. If you're going to provide a DAC, why not provide sensible analogue outs (rather than just adapters connected to the headphone out? And if you're going to market it as a DAC, why provide so many digital outs, which make it look like a USB-SPDIF converter?

For future reference: if there's serious interest in Bolder/TweekGeek offering a modified version of this, I'd put in a vote for having proper analogue outs installed.

Thanks.

Chad

Fife12 · « **Reply #15 on:** 27 Feb 2007, 07:08 pm »

Quote from: chadh on 27 Feb 2007, 07:05 pm

...And if you're going to market it as a DAC, why provide so many digital outs, which make it look like a USB-SPDIF converter?

I think this was made mainly as a USB-SPDIF and it happens to have the other features as secondary (ie. DAC and headphone out).

poseidonsvoice · « **Reply #16 on:** 28 Feb 2007, 05:09 pm »

This unit seems very similar to hagerman's USB unit. Uses the same chip, which yes is also a dac and has headphone outputs as well. Difference is that the Trends has its own PS, while the Hagerman uses the bus supply with very, very, good filtering and an SPDIF transformer to boot.

I'm currently implementing the HagUSB in a Peter Daniel NOS dac all in one case. SPDIF and USB inputs (via a switch) and analog outputs as well. Modded mine with Black Gates, Lundahl pulse transformer, Caddock resistors and PRP resistors as well. Many have done this in the past.

Anand.

sunshinedawg · « **Reply #17 on:** 6 Mar 2007, 07:05 pm »

Quote from: mgalusha on 27 Feb 2007, 06:08 pm

Hi Sean,

I'm going to try that this evening feeding the S/PDIF into the Altmann Attraction DAC. I'll let you know how it works.

Mike

Hey Mike, how'd it sound?

Sean

mgalusha · « **Reply #18 on:** 6 Mar 2007, 11:26 pm »

Quote from: sunshinedawg on 6 Mar 2007, 07:05 pm

Hey Mike, how'd it sound?

Sean,

Unfortunately I didn't have a chance to find out. I did add RCA outputs to the UB-10 and kept the digital so I could do this but the next day my wife had to go into the hospital so I didn't really have much time for experimenting. I did put the UB-10 into my system for a few minutes after I'd installed the jacks and it sounded quite good but also quite a long way from either the SB2 or the Altmann. A very nice little box but not at the level of either of those. I'm delighted with it for my work system though.

Here is a picture of the modified version:

As you can see, I decided to lose the AES/EBU XLR jack and just cut a small piece of brass and mounted a Canare 75R RCA jack.

Mike

sunshinedawg · « **Reply #19 on:** 7 Mar 2007, 02:53 am »

Quote from: mgalusha on 6 Mar 2007, 11:26 pm

Sean,

Unfortunately I didn't have a chance to find out. I did add RCA outputs to the UB-10 and kept the digital so I could do this but the next day my wife had to go into the hospital so I didn't really have much time for experimenting. I did put the UB-10 into my system for a few minutes after I'd installed the jacks and it sounded quite good but also quite a long way from either the SB2 or the Altmann. A very nice little box but not at the level of either of those. I'm delighted with it for my work system though.

Mike

Sorry to hear that. I hope she gets well soon.

Sean