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Best USB sound and midi module including Phantom mic input !

20K views 71 replies 12 participants last post by  brucek 
#1 ·
Hello, I think that I found an interesting product : Fast Track Pro - 4 x 4 Mobile USB Audio/MIDI Interface with Preamps
This external module includes :

  • Microphone XLR input with Phantom power to plug the EMC 8000 Mic. (replace my external mixer)
  • Midi interface to control the filters on the FeedBack Destroyer Pro
  • Digital and analog output to listen music on my HT from my PC

All that for less than 200$


What do you think guys ?
 

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#36 ·
I'm pretty sure Bruce doesn't mean to use the line in/out on the pc, but rather line in/out on the m-audio... specifically, the unbalanced ones...

I didn't read much above to see exactly what you're doing, but assuming youp're looking to run scans the way most of us do, albeit in your car, I think you'll want to send REW's (or TrueRTA's for that matter) output to your system via the line out (unbalanced) on the m-audio, so this way to capture that output's characteristics in the calibration file.

Bruce's point is that then switching from the unbalanced line in to the balanced "mic" in with the phantom power will introduce errors, but so small as to be negligible...

It certainly looks (from the specs) that the balanced input on the m-audio cannot handle the full scale input from it's own balanced output...
 
G
#40 ·
well , i did that and i followed the true RTA guide for dummies at the avsforum (audio setup section) i got a jiggly line that sort of trended up but a few secs later became flatter. nothing like the smooth line in the tutorial.
 
#41 ·
You got a "jiggly line" in TrueRTA or REW? Although I've played around with TrueRTA (the free, 1 octave resolution version) I'm not very familiar with it... but unlike REW, it only works as an RTA, so you have to let it average over time before you get anything significant...

Why not try using REW and see what results you get?
 
#48 ·
I would love to measure the pre-amp stage on the two units to compare but that is not a simple task.
Why is it not simple? Instead of a loopback cable on the right channel (which would measure as perfectly flat), you include the preamp or any line level device in that loop and take a full range measure. It will show the devices response from 0Hz to 20KHz....

brucek
 
#49 ·
You have a line level RCA out which you would want to route to a balanced mic level in. Wouldn't you need a device in the middle to convert to balanced? Then you would introduce whatever error that is inherent in that device. If I could just calibrate with an RCA to XLR cable I would, but I thought that was a no no.
 
#52 ·
It CAN be done, it just is not easy :D

After thinking about it for a while, I think I can do it with my DCX. I can go into the behringer with the RCA to XLR cable, then go out (no filters) balanced to the mic in. I can also come out of the behringer to an unbalanced line in to control for the response errors of the DCX. I know the behringer can handle unbalanced inputs and both balanced and unbalanced output so that just might do the trick.

I am sure you could also make a relatively simple circuit board to convert the unbalaced out to balanced but I am not sure if that would introduce any significant error.

All this to get a precise measurement at 6 or 7 hz where no EQ I know of can be used to tune the signal anyway :D
 
#53 ·
Another similar product, just as an option, with MIDI support and phantom mic power is the E-MU 0404USB. This product has reference quality measured behaviors(s) to boot, as verified by [1]3rd party measurements. In addition, the 0404USB device can be used without a computer as high quality stand-alone mic-preamp and/or ADC or DAC, with both coaxial and optical digital I/Os.

-Chris

Footnotes
[1]E-MU 0404 USB - A Top-Class External Audio Interface
http://www.digit-life.com/articles2/proaudio/emu-0404-usb.html
 
#54 ·
The ART dualPre looks like it could also be an economical option for a soundcard/mic preamp with phantom power, though it does not have any midi features. With independent left/right input gains it would allow straightforward line level loopback for the reference channel. The "monitor" outputs carry the signal from the PC/Mac when the mix knob is turned fully to the "Computer" position. http://www.sweetwater.com/store/detail/USBDualPre
 
#56 ·
Unless I am totally confused, I think the balanced out to in via 1/4" TRS cable works beautifully. Here is my reality check measurement after applying the cal file for the FastTrack Pro.

So is this accounting for the mic preamp or not?

I am still confused and a bit concerned by the apparent poor response using the RCA outputs.

Mike
 

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#57 ·
I think the balanced out to in via 1/4" TRS cable works beautifully
Great. :)

So is this accounting for the mic preamp or not?
No, the mic preamp is used when the XLR mic-in is used.

The reality check looks good. Carry on. I wouldn't be concerned about the minor difference the mic preamp would make. You can see the small debate about that here. Read the whole thread.

brucek
 
#58 ·
...the mic preamp is used when the XLR mic-in is used.

The reality check looks good. Carry on. I wouldn't be concerned about the minor difference the mic preamp would make. You can see the small debate about that here. Read the whole thread.

brucek
Thanks Brucek!

I guess I am confused because my understanding is that the 1/4" TRS input is exactly the same as using the XLR input (The FTP has a combined input jack) but it is just a different connector on the wire. Is this not the case?

Mike
 
#59 ·
my understanding is that the 1/4" TRS input is exactly the same as using the XLR input
You haven't said what type of soundcard you have, so it's hard for me to know. But most 1/4" phone jacks are for line-in and XLR are for the mic. Just look it up in your manual. It will tell you. The mic-in will be extremely high gain and would require a pad attenuator to reduce the line -level coming from the line-out to make it work in a loopback. Read the link I posted above to understand about that.

brucek
 
#60 · (Edited)
Thanks, the link you provided is exactly what I am talking about. However, I don't understand all the electrical engineering tech talk. You seem to have a much better handle on all this than I do. Maybe I'll have to post over there in order to figure this out.

Sorry you are correct. I have the M-Audio FastTrack Pro and the Behringer ECM8000. I thought is thread was specific to the FastTrack Pro but there have been several alternatives mentioned since it was started.

Anyway, the FastTrack Pro has two XLR and 1/4" TRS combo jacks as the only inputs (see pictures in the first post). Page three of the manual says:

"Microphone/Instrument Inputs (Mic/Inst) – These Neutrik hybrid connectors will each accept a low-impedance mic level signal on a standard three-pin balanced XLR or TRS plug, or a high-impedance instrument level signal on an unbalanced 1/4” TS plug."

Page fourteen of the manual has the detailed specs:

Mic Inputs (A/D):
Input Impedance: 2.7k Ohms unbalanced, 5.4k Ohms balanced
Maximum Input Level: from +24dBu @ min gain, pad on to -40dBu @ max gain, no pad
Preamp Gain: >40dB
Pad: -20dB pad

Line Inputs (A/D):
Input Impedance: 20k Ohms balanced and unbalanced
Maximum Input Level: +4.1dBu balanced/+1.9dBV unbalanced
Pad -20dB pad

Line Outputs (D/A)
Output Impedance: 150 Ohms unbalanced, 300 Ohms balanced
Maximum Output Level: +1.8dBV, unbalanced/+10.1dBu, balanced

:scratch: So I am still confused. Given that I am going from the balanced 1/4" TRS outputs to the balanced 1/4" TRS inputs in the loopback without using the available pad attenuator or instrument switch, it would seem as though I am including the mic preamp but I just don't know now.

Sorry I am such a newbie. Since it is the same physical input, I am confused about how I can know if I am using the input as a 1/4" balanced Mic input or a 1/4" balanced line input since it apparently matters. I thought as long as I was not using the instrument switch on the input, I was using the low-impedance mic level input.

Mike
 
#61 ·
So I am still confused.
Yeah, it is somewhat confusing. I think it matters not whether you're using balanced or unbalanced with respect to whether you're using mic preamp or not. I believe the mic preamp is used either way.

The confusion I have is whether they bypass the mic preamp and go directly to the line stage when using the Instrument/Line Selector Button. From the quote below in the manual it appears when using the 1/4" connection that they might bypass the mic preamp.

4. Instrument/Line Selector Button (Inst/Line) – This button selects the input level of the front panel 1⁄4” inputs. In the out position, the inputs are set to accept an instrument level signal (such as that from a guitar or bass) while in the in position they are set to accept a line level input (such as that from a keyboard or drum machine). Please note that the XLR input level is unaffected by this switch.

Since you are sending line-level to it with the loopback connection, you would want to have that button set to in, which may bypass the preamp.

The only way to be sure is to use the XLR input and use the pad button (very convenient) to lower the level into the mic preamp.

brucek
 
#62 ·
Thanks!

I will get a cable that goes from 1/4" to XLR and do it that way. Then it sounds like I am guaranteed to be using the mic preamp. So since the input has a built-in pad, I don't need to soldier one up like people are doing in the other thread right? It looks like I have everything I need on the unit itself to measure the audio interface and the mic preamp (as long as I use the XLR input) right? Again, it probably makes little difference anyway but if I can do it, why not?

Thanks for your help. I would have never figured this out on my own.

Mike
 
#63 ·
So since the input has a built-in pad, I don't need to soldier one up like people are doing in the other thread right?
Correct.

It looks like I have everything I need on the unit itself to measure the audio interface and the mic preamp (as long as I use the XLR input) right?
Correct.

Again, it probably makes little difference anyway but if I can do it, why not?
Yep, it never hurts to remove all the bias that your test equipment introduces to testing. That way you know the response graphs are as accurate as possible.

brucek
 
#64 ·
So what is the consensus on this product or others very similar? I read through the thread but I just never really got a firm feeling on it.

I'll be starting fresh so I if I can streamline this from the start...I assume that would be the thing to do.

I already have a ECM8000, Radio Shack Digital SPL, Laptop running XP, external creative live 24-bit sound card, REW downloaded, and plenty of RCA cables.

Currently I'm looking for a BFD and was looking for a mic preamp/mixer like the 502. But now I'm thinking about getting the M-Audio Fast Track Pro instead of the 502.

I want to be able to communicate directly with the BFD via computer so I would either have to get the expensive USB to MIDI converter cable ($40 is expensive to me) or just get midi cables to go from this M-Audio device to the BFD which I assume can be had for a lot less than any converter cable.

Anyway...looking for additional thoughts. I think for me it would be cheaper to get the external mixer and cable...think I can get a cheaper cable if I look hard enough...just wonder if all of those cables are basically the same or is there some real good reasons for the ones suggested in the REW FAQ and not others.
 
#66 ·
From my perspective, the FastTrack Pro is tough to beat. You get everything in one box so it is very convenient and when you consider to price of getting each piece separate, it isn't a bad deal at all. I have played with mine for a while now and I am very happy with it. If you get this cable: http://www.monoprice.com/products/p...=10244&cs_id=1024404&p_id=4775&seq=1&format=2 you can calibrate the mic preamp and audio interface at the same time. All I can say is that I have been very happy with the FastTrack Pro and would recommend it to anyone. It is a good product and a good value.

That being said, it sounds like you already have most of what you need so if you are on a tight budget (and who isn't these days) then there is no harm in going the separate (cheaper) route. You'll just have more boxes/cables to manage - no big deal.

Mike
 
#69 · (Edited)
I don't believe the 502 has phantom power. You need the 802 or higher to get it.


It remembers the informations - no problem.

brucek

Unless I'm reading the specs wrong it does. The way it reads it's got everything the others have in that model line except for a power amplifier which I'm not totally sure is all that important.

http://www.behringerdownload.de/UB-GROUP_1/IMPL%20Tech%20GLOB_P0180_M%20Web%20EN_2008-06-19_Rev.5.pdf

EDIT:
I think that manual is just confusing the way it's written now that I look at the picture there isn't a switch...looks like that's going right back on ebay. Hopefully i can get my money back out of it.

EDIT: Scramble Mode

Is there a MIC that would suffice for usage with REW in lieu of not being able to use phantom power? I'm real sure I can sell the MIC I've got pretty easy but unloading this UB502 might prove a bit more challenging.
 
#71 ·
okay, i have a splitting headache from being confused even though i know my confusion is unwarranted and will be realized once i get past this learning curve. i'm doing wiki lookups on the difference between balanced and un-balanced cabling so you know what level of audio smarts i am up to right now :mooooh:

anyhoo i am hoping someone can help me since i have deviated from the basic manual of how to hook up your sound card with rew and went the route with m-audio fast track pro. i picked this solution because its low cost for me since a buddy of mine works in audio and let me borrow his m-audio fast track pro device, xlr cable and his paa3 analyzer. aside from his gear i also have the FBD Pro 1124p, ecm8000, mic stand and an old sound card.

just to see if i was getting sound recording from the mic thru the m-audio ftp device to my computer via usb, i popped in a music cd and played some jams while watching REW graphs. sad to say i am not seeing a thing. i configured the REW software same as i would for an external sound blaster live card but this yielded nothing. i am not sure what buttons to depress on the m-audio ftp device either to know if i am doing something wrong. at this point i just want to see a graph being formed in REW.

if anyone know of a 10 step process i can follow i would greatly appreciate it.
 
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