condensor mic

[drathbun]

Well I'm still mystified by the low gain of the condensor and that you need 9/10 to get a good signal. What kind of preamp is in the M-Audio? Does it have a preamp? I run my Apex 435 to a Behringer MIC200 Tube Preamp and if I bring my input channel up to 3, I can hear a caterpillar crawling across the carpet in the next room!

[Steve]

Due to differences in architecture (don't ask me!), FireWire is faster in sustained throughput than USB 2.0. But not 30 times faster.

Actually Firewire can go over the 1.1 USB vs Firewire (30 times faster performance.) 

Read below about FireWire vs. USB 2.0

Question: Which is faster Hi-Speed USB 2.0 or FireWire?
Answer: In sustained throughput FireWire is faster than USB 2.0.

Question: If Hi-Speed USB 2.0 is a 480 Mbps interface and FireWire is a 400 Mbps interface, how can FireWire be faster?
Answer: Differences in the architecture of the two interfaces have a huge impact on the sustained throughput. 

FireWire vs. USB 2.0 - Architecture

FireWire, uses a "Peer-to-Peer" architecture in which the peripherals are intelligent and can negotiate bus conflicts to determine which device can best control a data transfer.

Hi-Speed USB 2.0 uses a "Master-Slave" architecture in which the computer handles all arbitration functions and dictates data flow to, from and between the attached peripherals (adding additional system overhead and resulting in slower data flow control)

FireWire vs. USB 2.0 Hard Drive Performance Comparison
Read and write tests to the same IDE hard drive connected using FireWire and then Hi-Speed USB 2.0 show:   
Read Test:
5000 files (300 MB total) FireWire was 33% faster than USB 2.0·   160 files (650MB total) FireWire was 70% faster than USB 2.0
Write Test:
5000 files (300 MB total) FireWire was 16% faster than USB 2.0·   160 files (650MB total) FireWire was 48% faster than USB 2.0

The above is why many USB audio interface users complain about latency problems.  Just read some reviews at the retailers and you can see the USB can sometimes be a pain to use.  In fact most digiital/video is done with IEE 1394 not USB 2.0

[ronmac]

IMHO the differences between USB 2.0 and Firewire (IEEE394) transfer rates are not that crucial to the majority of audio users. Audio doesn't present nearly the demands on a system that video does.

The main reason that USB users have problems is due to the number of non-audio devices (printers, mouse, PDA, camera, keyboard, etc.) they have connected to their USB Bus. It is recomended that you disable as many as possible when you are doing some serious recording so that their is no competition for the bus bandwidth.

Given a choice I would select a Firewire interface and install a seperate controller for it alone.

Like everything computer related, most users have different hardware/software setups and problems cannot be attributed to anything as simple as which input device you are using.

[Gemnoc]

Actually Firewire can go over the 1.1 USB vs Firewire (30 times faster performance.)

Steve, I don't understand your sentence. :huh:

Funny, I found the same page with this comparative info between USB and FireWire.

My point was and still is, FireWire is not 30 times faster than USB 2.0. Your examples show 70% as the biggest differential for file transfers. 

And the fact is, most USB devices nowadays are USB 2.0 compliant. USB 1.1 is obsolete.

Cheers

[Gemnoc]

Well I'm still mystified by the low gain of the condensor and that you need 9/10 to get a good signal. What kind of preamp is in the M-Audio? Does it have a preamp? I run my Apex 435 to a Behringer MIC200 Tube Preamp and if I bring my input channel up to 3, I can hear a caterpillar crawling across the carpet in the next room!

The M-Audio includes preamps.

Here's what it says about the mic inputs:

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
Channel-to-Channel Crosstalk < -110dB
SNR -101dB, A-weighted
Dynamic Range 101dB, A-weighted
THD+N 0.005% (-86dB) @ -1dBFS, 1kHz
Frequency Response 20Hz to 20kHz, +/- 0.1dB
Pre-amp Gain >40dB
Pad -20dB pad

[Zach]

The M-Audio includes preamps.

Here's what it says about the mic inputs:

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
Channel-to-Channel Crosstalk < -110dB
SNR -101dB, A-weighted
Dynamic Range 101dB, A-weighted
THD+N 0.005% (-86dB) @ -1dBFS, 1kHz
Frequency Response 20Hz to 20kHz, +/- 0.1dB
Pre-amp Gain >40dB
Pad -20dB pad

Does the Fast Track Pro use M-Audio's software mixer?  If it does, be sure the gain is up there.  Also, I'm sure it is, but be sure the phantom power is on.

[sdelsolray]

Yeah, something's not quite right with your mic and preamp.  You shouldn't have to turn it up that high to get a full signal.

[Gemnoc]

The phantom power is on. I'm plugging the M-Audio through my PC's front panel. Someone told me the 2 front ports provide lower power than the ones at the back, and that may be the cause of the low signal (not enough power to the mic :huh:). I'm sceptical since there is no such mention in my motherboard user's guide. But I'll give it a try (back USB port) anyway.

[ronmac]

The maximum gain on the preamp is only 40 db (typical studio mic pres offer up to 65 db) so the gain will need to be set fairly high on this device for the mic.

[/b]I also noticed that there is a 20 db pad. Make sure that is not engaged as it will drop the mic signal by 1/2.

[rockstar_not]

The maximum gain on the preamp is only 40 db (typical studio mic pres offer up to 65 db) so the gain will need to be set fairly high on this device for the mic.

Bingo - this is the reason right here.   No more mysteries.  It pays dividends to pay attention to gain and signal to noise ratio when shopping for an I/O device.

-Scott

[ronmac]

As long as the pad is not engaged, that is enough gain for a modern condensor. You don't have the advantage of the headroom of a more upscale device, but hey, these are priced and produced for a home recordist, not someone doing a 40 seat orchestra recording.

[Gemnoc]

Thanks for your input guys. It's a hardware limitation then, and I have two choices: get a refund or keep it and work within the limitations. I think I can do the latter.

[Crunchy Wacko]

The maximum gain on the preamp is only 40 db (typical studio mic pres offer up to 65 db) so the gain will need to be set fairly high on this device for the mic.

[/b]I also noticed that there is a 20 db pad. Make sure that is not engaged as it will drop the mic signal by 1/2.

Ok guys..spell it out for me. PAD..what is it?  Gemnoc..did you have it engaged on your recording?

[ronmac]

A "pad" is an attenuator that can be applied if you are micing something that is very loud, ie. kick drum, and would otherwise overload the rest of your signal chain. In simpler terms it's a gain control with a fixed amount of reduction.

[sdelsolray]

The maximum gain on the preamp is only 40 db (typical studio mic pres offer up to 65 db) so the gain will need to be set fairly high on this device for the mic.

[/b]I also noticed that there is a 20 db pad. Make sure that is not engaged as it will drop the mic signal by 1/2.

Yep, that's the reason for sure.  40dB gain is not an awful lot.  Of course, it depends also on the sensitivity spec (i.e., output rating) of the mic you use.

I would strongly consider returning the interface and getting one with preamps with higher gain, 50dB at a minimum, 60dB+ would be better.

[Crunchy Wacko]

Yep, that's the reason for sure.  40dB gain is not an awful lot.  Of course, it depends also on the sensitivity spec (i.e., output rating) of the mic you use.

I would strongly consider returning the interface and getting one with preamps with higher gain, 50dB at a minimum, 60dB+ would be better.

Would it make a difference if we were using a passive pickup rather than a MIC?  The next M-audio device with a increase in GAIN is the Firewire 410 model at $150 more. ..it has 66db gain

[ronmac]

The passive pickup will not require as much gain as most microphones, so it will be fine.

The AT2020 has a fairly respectable output so 40db of gain will work, although as I mentioned earlier you won't have a lot of headroom.

The Firewire 410 has a much larger feature set so the extra money is well spent, if that is what you are after.

Regardless of what you are buying, the budget always dictates the available choices.

[Gemnoc]

Gemnoc..did you have it engaged (PAD) on your recording?

I am the kind of people who read their manual before using their stuff. Some were questionning if I had put the phantom power on, now you ask about the pad button... So will you all stop taking me for a fool? ^_^

Short answer, no it was not engaged. :WNK>

You are not cool guys.  :WNK> Now I just called the store to see if I could switch the FastTrack for a FireWire 410 unit.

Another possibility is to exchange it for the Tascam US-122 that dberch mentioned. About the same price as the FastTrack Pro. But I don't know what is the input gain level. Out of the technical specs that are gibberish to me, does anything here equates to the input gain?
    - gain attenuation @ 1kHz..... better than -90dB
    - nominal input levels (MIC L & R, XLR balanced) ..... -54dBU (TRIM=max) to -16dBU (TRIM=min)

Apart from having more headroom, what is the advantage of more input gain? At 9/10 it seems I can record reasonnably well. At max, it is too sensitive to have good result. I hear many ambiant noises like the computer hum, the "swoosh" of my satin finish guitar on my clothes, even my loud breathing (damn allergies have me congested). So if I can get still more gain what would be the purpose? Or does that mean I could record farther from the mic (say 12 inches) and retain a bassy tone, not like the thin sound Crunchy Wacko reported on my first sample?

[sdelsolray]

The passive pickup will not require as much gain as most microphones, so it will be fine.

The AT2020 has a fairly respectable output so 40db of gain will work, although as I mentioned earlier you won't have a lot of headroom.

The Firewire 410 has a much larger feature set so the extra money is well spent, if that is what you are after.

Regardless of what you are buying, the budget always dictates the available choices.

Ron

Agreed on the pickup issue.  As to the mic and gain, I disasgree.  The AT 2020 has a sesitivity spec of 14.1 mV/Pa, quite average for a condenser mic.  For example, a Schoeps CMC6/MK4 has a spec of 13 mV/Pa.  Compare that to a Neumann M149 tube mic, considered by many as a "hot" mic.  It has a 47 mV/Pa signal.

The AT 2020 will not work well with only 40dB of preamp gain available, and like you said, there would be no headroom with a 40dB preamp.

[Gemnoc]

So that means I would benefit from upgrading to the FireWire 410... Or that I should have put more money in the mic. Well, there goes another chunk of my overtime money. :WNK>

This Neumann mic has a pretty steep mV/Pa to $ ratio. ^_^