Advice on buying an USB audio interface

[luispa]

Thank you for your reply 1984.

Is the Focusrite USB 6 supported by ALSA driver? I heard it's not class-compliant.

[1984]

Sorry for the late answer. I don't drop in here too often.

I'm talking about this interface just to avoid confusions: http://www.thomann.de/gb/focusrite_saffire_6_usb.htm

It worked out of the box in my case. But it might be good to get some info of someone who really uses it and not only tested it.

[rgwan]

I am trying to make one use a high speed USB microcontroller with 2 I2S FULLDUPLEX and 8uarts. It will be an opensource soundcard(Use the UAC2.0 protocol), and on Linux, it will not requires any special drivers more.
ADCs use 2 x PCM4202. Main DAC use the PCM1798, Earphone DAC use the PCM1793. It will be a 4IN 4OUT interface in 48KHz-192KHz(44.1X will be support too). And could work standalone with external power supply or internal battery.
The Input ports will be 2XLR-combo and 2TRS port which can be pluggin in 2mics and 2guitar at same time. MicPreamp has -6 ~ 60dB gain range by OPA1602 & OPA1632, full differencial.
This soundcard will have 2 TRS for main dac output, full differencial, and 1TRS for earphone out. Line driver will be TL074.
This thing can be very heavy to USB powering, Now I am use external power supply to debug it. I don't know can it be powered from usb with all functions on.

[rgwan]

As for the BOM price...It.will be lower than 70$, if you are interested in it, you can make it yourself, but MCUs must buy from AlphaScale or from me.

This MCU is very cheap, but hard to buy and develop must under NDA. So I have to rewritten the SDK on datasheet....It is a pretty hard work

[luispa]

Thank you for all your replies. Finally I ended buying 4 used interfaces on eBay (average price was around $50). It's hard to go wrong in that price range. I bought:
- Lexicon Lambda.
- Presonus Audiobox.
- Mackie Onyx Blackjack
- Presonus 22VSL

This is what I found after testing and comparing these units:
- Lexicon Lambda. Nice construction but not too much preamp gain. Also headphones amplifier is weak and lacks of low end, my laptop sounds better on headphones. This is an issue for tracking loud instruments. Also the 1/8" headphones jack is the cheap detail.
- Presonus Audiobox: Like the Lambda, preamplifier has not enough gain if I decide to use dynamic microphones. Also headphones amplifier sounds cheap and worse than my laptop. This unit also has a higher noise floor compared with the other interfaces.
- Mackie Onyx Blackjack: I love this interface despite it weird look, more than enough gain and the headphones output is great. This unit also has a very low noise floor. Easy to operate.
- Presonus Audiobox 22VSL: This is also a winner, it's on pair with the Mackie but it's USB 2.0 and allows to record up to 96KHz.

I'll keep the Mackie and the 22VSL and I'll sell the old Audiobox and Lambda interfaces.

Thank you again for your help, it was really useful.

[macrobbair]

I've got a presonus audio box and just cannot get it to work, under linux mint 17 I plug in the usb and nothing happens, under windows 8.1 I get:

USB device not recognised

The last USB device you connected to this computer malfunctioned
and Windows does not recognise it.

Recommendation
Try reconnecting the device. If Windows still does not recognise it, your
device may not be working properly.

I am a windows phobe so would prefer to get it to run under linux mint - any hints?

[luispa]

I've got a presonus audio box and just cannot get it to work, under linux mint 17 I plug in the usb and nothing happens, under windows 8.1 I get:

USB device not recognised

The last USB device you connected to this computer malfunctioned
and Windows does not recognise it.

Recommendation
Try reconnecting the device. If Windows still does not recognise it, your
device may not be working properly.

I am a windows phobe so would prefer to get it to run under linux mint - any hints?

Hi,
Both Presonus Audiobox interfaces (the original and the 22VSL) worked right out the box. I've had no problems with Mint 17 KDE. I'm afraid your problem is hardware related. The first and cheapest test you can do is to change the USB cable and see what happens.

[chaocrator]

for those who will read this thread looking for advice: consider Native Instruments Komplete Audio 6 as a very good option in this category.

[macrobbair]

Yes, I've come to the conclusion that there is something wrong with the box: for a very long time I thought that it was me.....

[ebozzz]

Does anyone have any experience with the Behringer U-PHORIA UMC202HD? There seems to be a great deal going on right now with those. $49.99 USD for the interface or $79.99 if bundled with a TC-Helicon dynamic microphone. Most soucres seem to be selling the Behringer for $149.99......