XLR Confusion On Mackie Mixer

Bobbsy said:
Finally, if you DO trade in your mixer...I suggest you don't buy another mixer. It doesn't help you at all in recording. A basic USB interface with Direct Hardware Monitoring will do all you need...easier and with as good/better quality for less money. There are lots of "which interface" threads here.
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Thanks for the setup tips.

I wound up with the Mackie because I'm nearing the end of my hobby money stash so I had to seacrh craigslist for a used low price AI. The original owner bought it two weeks before I bought it from him so it's new. It has four XLR inputs and other useful features including effects. The name seems to be popular, it's very well built and it only cost me $100. They go for $230 or a little less on sale so it seemed like a no-brainer. I had no luck finding an audio interface that was acceptable (on CL) so I bought the Mackie. Although it's a live performance mixer they do market it as a home recording mixer as well. Usually when I buy something I buy gear that's flexible and this fit that description. I think if I do post a trade ad on CL I will be able to get a good AI for it since I bought it for less that 50% of retail and it's still basically new. I'm going to give it a little more time though.
 
Bobbsy said:
As far as I can tell, Mackie don't provide ASIO drivers for their ProFX range of USB mixers...the web site says "no drivers necessary" which is a euphemism for "we can't be bothered to provide proper drivers so you're stuck with the MME rubbish". Sad that a once-reputable company like Mackie skimp like this...even Behringer provide drivers for most of their stuff.
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Actually, "no drivers necessary" is a good thing at a gig if you might have to press another computer into service on short notice. It just uses the stock usb audio driver that works on most devices, though perhaps only at 16 bit. That seems like a reasonable arrangement for a cheapish USB enabled live mixer.
 
We'll have to "agree to disagree" on that. I try to keep Windows MME drivers as far away from any serious recording as I can...but then I've always carried my own computers with me and they were set up for the job at hand. FYI, my concerns are more with issues of latency and also the way Windows drivers are shared among other hardware and software on the computer.
 
Yeah, the Mackie USB is only 16 bits, and keep the volume knob on it down or you're going to get some high-pitched whining in the sound (that WILL be recorded). I used mine however the standard (MME?) drivers worked and never had any issues with it.

Don't bother trying to sell the Mackie at this point - you might get your money back but the options for $100 audio interfaces are limited. IF you need 4 mic preamps, the new Tascam 1200 is your least expensive choice unless you find a used one somewhere.
 
...4 mic preamps but you can only feed two channels at a time into your DAW via USB so a 2-preamp interface may be enough.

However, he didn't initially say he got it for $100 so it's probably worth keeping going with it. I would reinstall Asio4All rather than using the basic drivers...and you'll have to set up you monitoring in the mixer to avoid latency though. We can talk about that once you can record at all!
 
Using right microphone(s) for guitar recording is better most case. Recording direct you lose loudspeaker, room and microphone affects, recording becomes to direct and "dead". Reflecting room is better for guitar recording as damped room, so many case people use empty room or even tiled bathroom for it :) Concerning XLR to TRS symmetric cables - please check cable phasing, XLR contact #1 (shield/ground) must be sleeve of TRS, #2 (+) must be tip of TRS, #3 (-) must be ring of TRS.
 
I have just looked at this thread and the photos of the mixer that the originator has and the request for information.

The mixer has XLR connectors for BALANCED MICROPHONE input. If you put any form of line input into these (ie -10db, +4db, etc) you will greatly overload the microphone input (like connecting a 110/240V supply into a 6V torch globe or similar).

You will note that each of the inputs just below the XLR connector has another input socket (1/4" -- 6.5mm) that is marked "Line". THIS is where you should be connecting the XLR line outputs from the pre-amp unit (forgotten the make/model). More on this below!!!!

You will also note that the "line" input on Chnl 1 is marked as unbalanced. This is for things like a mono feed from the line output on (say) a guitar amplifier or possibly the mono output from a synth, etc.

The "line" inputs on Chnl 2 + are marked as balanced/unbalanced --- this is where you should be connecting the XLR outputs from the Pre-amp unit, BUT you will need the following.

As the pre-amp has XLR outputs, the outputs will be balanced (ie +ve & -ve wires), so you will need a balanced XLR lead (pin 2 hot, pin 3 cold, pin 1 earth) to a balanced (ie stereo or TRS) 1/4" jack plug (wired hot to tip, cold to ring, earth to sleeve) and you will need two of these leads (one for each of the pre-amp outputs) and you would plug these into (say) Line input Chnl 2 & 3.

Now (for the first time at least --- until you know that all is OK) before turning on the mixer's power switch I would be connecting everything up and have a good level signal coming from the pre-amp, then I would be raising the level of both the respective channel faders and the master fader to the marked 0Vu point on the fader and turning the channel Gain control to the fully counter-clockwise position (marked -20). Now I would be turning on the mixer's power and then slowly raise the level of the Gain pot on one of the channels until you get light on the signal LED and reading on the master Vu meter (NOT 0Vu but say 4 or 5dB below), I would now lower the channel fader for that channel to the minimum position. Now raise the level of the other Gain control until it gives good signal (again say 4 or 5db below the 0Vu mark), now while leaving the second channel set, raise the level of the first channel and you should see the master VU meter start to rise and hopefully when the first channel fader gets to its 0Vu position, the master Vu should be around the 0Vu mark.

Now depending upon the signal being fed into the mixer you will most probably have to adjust the levels of the Gain control and channel faders to get the exact levels you require for the song you are mixing/recording ---- this is called "mixing".

Although long winded I hope that the above puts the originator in the correct position with his set-up and is not too confusing and it is has been presented this way and in this detail as I am presuming that the originator is just starting out and is not familiar with audio electronics, console operating (especially gain structure) and recording/mixing techniques.

David
 
Surely you just read the manual. For years many mixers simply padded the preamp to provide a line level input. Others simply changed the preamp circuitry to allow line level and mic level on one fader. Line inputs on jacks were often just balanced, wired to the same three pins of the XLR with unbalancing by the sleeve shorting? Over the years we just get used to xlr being mic level and jack being line, but that's just convenience and commonality of design.
 
CSP said:
The mixer has XLR connectors for BALANCED MICROPHONE input. If you put any form of line input into these (ie -10db, +4db, etc) you will greatly overload the microphone input (like connecting a 110/240V supply into a 6V torch globe or similar).
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That's an overstatement. Connecting +4 signal to a mic input won't burn anything up. If it's not too hot a +4 signal it might not even clip.
 
Best practice would be to feed a line level source to the line inputs, but...

If you go to the spec on the Mackie schematic, the input gain for a mic source (i.e. the XLR) is 0 to +50dB. The gain on the line inputs simply puts a 20dB pad in circuit, changing the available to to a range of -20 to +30dB. Based on this, there's a reasonable chance the OP could get away with XLR inputs as long as his source isn't super hot. It certainly doesn't provide a danger of burning anything out like plugging a torch bulb into mains would do.
 
Guys,

My comment about the torch globe was not designed to be specific, but rather as an example of why you would not put a +4db signal into a -50db expecting microphone socket, and it was meant for someone who I am presuming is not all that (if at all) experienced with consoles, audio levels and audio electronics.

As a matter of interest, I have been involved in the audio industry (ie recording, FOH, teaching, writing and the electronic design and construction of consoles, amplifiers and tape recorders) for just over 50 years and for most of this time at the VERY highest level and working for some of the most famous artists and in some of the most famous venues and studios --- I AM NOT TRYING TO BIG NOTE MYSELF --- and I can state that I have seen at least four examples where an inexperienced operator has connected an XLR connector carrying a +4db signal to a -50db mic input on a console (an definitely not cheap ones) and has caused the channel so connected to fail (ie had to be fully repaired). In fact one operator when doing this said to me "I don't see why I can't do this as the output of the recorder (+4db) is an XLR socket and the input on the console (-50db) is XLR socket, so naturally an XLR lead will connect to any other XLR socket". He was not long after this very surprised when not very far into the performance he lost all signal from the two channels connected to the tape recorder.

He very soon learned that not all XLR plugs/sockets are inter-connectable.

As a result I feel that what I stated in my initial posting is very good information to impart for the originator of this topic and for many others who are just starting out.

Still a great forum and even greater fountain of knowledge.

David
 
So a little less than once in a decade with inexperienced operators. Yes it can happen but it's rare. Perhaps it was a very hot signal and a lowish impedance input (on vintage gear?) that allowed enough current -> watts -> heat or something. I've been doing sound for "only" twenty-some years and it's never happened in spite of getting ridiculously hot line level signal from bass amp direct outs many times, hot enough to massively clip the mic pre and make me adapt it to TRS so I could use the padded line input.
 
My current mixer has nothing but XLR inputs plus a 20dB input pad switch on the top surface. Nothing's ever been hurt by forgetting to throw the pad switch in either direction...and, indeed, I've occasionally deliberately resorted to turning off the pad for some lowish, non standard "line" sources.

Having said all that, one compelling argument to use XLR to TRS adaptor leads on mixers like the Mackie is the potential presence of phantom power on the XLRs. Since it's a global switch, it's all to easy to have it one accidentally--and some line sources "don't like it up 'em".
 
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