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Is running my cheap-ass mackie's mic preamps at unity gain going to reduce the affect they have on the tone of the input in any way?

Naturally, I'm going to avoid this whenever I can, but how close does leaving a preamp at unity gain correspond to a true bypass scenario?

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AudioGaff Fri, 10/31/2003 - 23:56

Originally posted by Jonathan El-Bizri:
Is running my cheap-ass mackie's mic preamps at unity gain going to reduce the affect they have on the tone of the input in any way?

Naturally, I'm going to avoid this whenever I can, but how close does leaving a preamp at unity gain correspond to a true bypass scenario?

Yes and No. The unity gain setting is more for use with the line level input. When using a mic into the XLR, it will need a certain amount of gain with different mics needing more or less gain so you can't expect a mic to ever be at unity gain level. If there is bypass like range in the preamp it should be at unity gain. I find that the Mackie seems to suffer at any gain setting when fast, hard, dynamic signals are sent through it.

In general it is often but not always, that when a large amount of gain is required, more of the mic pre circuit imparts it's character so that it sounds different depending on how much gain is used. This is usually a result of non linear performance and it can sometimes be a good thing.

I find the Mackie pre's to be linear through out most of it's range therefore not having any real character of it's own. Where I do find the harsh/brittle character of the Mackie is when high gain is used through the channels and the mix bus on fast, hard, dynamic signals. It seems to get much worse the more gain that is needed or used.

sserendipity Wed, 11/05/2003 - 09:16

Originally posted by AudioGaff:

Yes and No. The unity gain setting is more for use with the line level input. When using a mic into the XLR, it will need a certain amount of gain with different mics needing more or less gain so you can't expect a mic to ever be at unity gain level.

Sorry I should have been more specific - for this particular setup, I'm intending of feeding the mackie with the output of another pre, and was whether I should work out a mult in order to bypass the mackie on the way to the recorder, while still feeding it for the monitors, or whether I could get away without doing this. Naturally, I'm going to be playing around with it first, but time will be limited, so I was looking for other people's opinions, and hopefully someone else's better understanding of preamp signal structure.

Interesting that you find the mackies to be harsh and brittle - I hear that too, but more frustrating to me is the mush that they turn the midrange into. I only use the mackie for mixing monitor mixes as a result.

Thanks!

Jon

KurtFoster Wed, 11/05/2003 - 10:09

Jon,
If you are using another pre amp, then why even pass the signal through the mackie on the way to the recorder? Bypass that mackie! Patch the output of the mic pre directly to the recorder. There is no sense in running the signal through 2 pre amps, or a mic pre and a line amp.

In response to the other part of your question, many of the "less expensive" pres seem to have a certian range in which they sound good. That is they sound best when dialed into a sweet spot because they act more liniear within that range. Better pres can sound good at all settings. This is one of the things that seperates good pres from not so good ones..

AudioGaff Wed, 11/05/2003 - 11:57

I'm intending of feeding the mackie with the output of another pre, and was whether I should work out a mult in order to bypass the mackie on the way to the recorder, while still feeding it for the monitors, or whether I could get away without doing this.

Ya, if at all possible, bypass the mackie or anything else. If you are just using the mackie for monitoring, then you could use a mult/split from the outboard preamp into both the recorder and the mackie. You should also be able to just use the recorder outputs into the mackie TRS inputs with the trim set at unity gain or less.

anonymous Thu, 11/20/2003 - 12:05

This actaually is of some interest to me given the fact I can't bypass the Korg D1200's internal preamps, and I use an RNP. Most Korg users who use external pres put the trim on the Korg's inputs down to zero (a.k.a unity gain) and use their external pre to get a hot signal.

While I'm aware that just by running the signal this way, the Korg's pres may be doing _something_ to the signal even at unity gain because the current has to flow through the korg preamp signal path, but I've never been clear on if that _something_ can be percieved if the korg's pres are at unity gain. In other words, if the korg pre is not doing the work of increasing the amplitude of the signal, does the quality of it's linearity become a non issue? Or can it's linearity still be a factor when it's given a signal that's been pumped up by a preamp put before it?

This may beg the question of how the korg's pres are designed, and how they behave when at unity gain but given a hot signal. I don't have the answers to those questions obviously, but I'm curious from an electronics/theory perspective if the pre at unity gain will _significantly_ affect a signal when it's fed a hot signal pumped up from another pre put before it.

thanks

anonymous Fri, 11/21/2003 - 07:40

The only way to bypass the pres on the korg is to use the digital ins. Until I can afford a good set of converters to go RNP->Lucid->Korg digital in, I have to go through the Korg's pres at unity gain straight from the RNP. Trust me, there are no inserts on the D1200, no way to bypass the pres... otherwise I'd use 'em. Don't even start on how lame that is... I already know.. ;)

That's why I'm interested in this subject.

KurtFoster Fri, 11/21/2003 - 13:42

Ted,
Please forgive my ignorance... I have never used a Korg D1200 so I can't speak from expierence. I went to the Korg site and checked the unit out, seems there is a new model the Mk II ... I see line as well as XLR ins on inputs 1 & 2 and line ins for inputs 3 & 4. Does your Korg have these same inputs? If it does, that is where you should run your RNP... If this is the case, would you please do me a favor and record a snip of acoustic guitar using the same mic and position with the pre from the Korg and then the RNP.. I'm curious to hear how they compare..

KurtFoster Fri, 11/21/2003 - 13:51

Originally posted by Jonathan El-Bizri:
Is running my cheap-ass mackie's mic preamps at unity gain going to reduce the affect they have on the tone of the input in any way?

Naturally, I'm going to avoid this whenever I can, but how close does leaving a preamp at unity gain correspond to a true bypass scenario?

As AG points out, with the Mackie, less is more. The less of the mixer you use, the better it's going to sound. If possible, take the output of the pre from the insert send.. bypassing the rest of the mixer.

My expierence with Mackies has taught me that when I keep the gain under -10, it seems to sound better. The Mackies seem to work better with -10 gear rather than +4. Keeping the signal peaks to -10 db, will help it sound much cleaner..

Best choice probably is, get a good mic pre, something that can get a good hot level without chokeing. Rane makes a good inexpensive mic pre that has good headroom and is affordable.

anonymous Sat, 11/22/2003 - 17:03

from experience mackies sound best when.........
you take an input dirrectly from an aux return bypassing everthing using only one gain stage before it hits the Master Fader or main mix.
The Main fader on the mackie is the noisiest part of the mackie, so like kurt said if your going to run things through it take it directly out of the insert which also acts like a direct out, also bypassing the EQ section, which infact degrades your audio signal. The only way to bypass an EQ on a cheaper mackie is to not use a channel strip or take it out of the insert point.
And once again if you don't need to run your audio through the mackie don't do it.

anonymous Mon, 11/24/2003 - 08:57

Kurt: My Korg does not have the same setup as the MK II... there is NO way to bypass the pres, other than going through the digital ins, which I cannot do since I don't have an external converter. If the Korg D1200 allowed me to bypass the pres I would. I don't need help on understanding how to use the RNP and the Korg together, or what an optimal signal path should be in my setup. That was not a newbie-esque question, in other words...

I mentioned the Korg only because it represents a scenario where the original question is a real-world issue: since I have to use the Korg pres, albiet at unity gain, what are they doing to the signal? Whatever it is that's being done, should it be audible? that's all I'm curious about here.

An answer to this question can drive the vailidity of doing a pre comparison between the korg and rnp... the only test I can give you is:

Larrivee D-03
Into
Earthworks SRO/Rode NT1000 (pick your poison)
Into
RNP
Into
Korg via it's pres at unity gain

vs.

Larrivee D-03
Into
Earthworks SRO/Rode NT1000 (pick your poison)
Into
Korg using it's pres at 3 o clock.

I cannot give you a path that does not include the Korg's pres; I can only give you a path that includes the Korg's pres at unity gain.

Personally, I hear a difference, but I'd hate to go through a test recording to have it questioned
because I can't bypass the korg's pres...

If I had an external A/D converter, I could bypass the pres, but I don't, so I can't.

My overall impression of the Korg's pres are that they are clean, but brittle and thin. Think a colder mackie. Cold and thin, but not noisy. The lows seem ok (I've recorded my djembe a few times with them). That's the best I can do. I don't like them... they make my tracks really sound "digital" if you know what I mean. I use them when recording my kids running around, and they are fine for that... I'd even say you can get NPR-ish field recordings with them, but the gain on the trims is such that you have to peg the trims past 3'0clcok and then you can get overs real easy since there's no limiter in front of the converters on the korg. the pres are quiet unless you peg them, in other words, and then you run the risk of overs.

anyway, I'm still mostly curious about what can happen to a signal when it's passed through some pres at unity gain.

and let me know if you still want a comparison between the 2 pres, given the fact I cannot truly byass the korg's pres in any scenario.

KurtFoster Mon, 11/24/2003 - 10:49

Ted,
No matter what gain setting you use, going out of the RNP into the Korg mic input is going to run the signal through 2 mic pres.. I don't think the amount of gain applied at whichever stage is not going to make much difference other than each of the pres may have a sweet spot where the respective pre runs in a more liniear fashon.. I'm not questioning you but I find it difficult to understand why Korg would make a recorder that didn't have any line inputs??

anonymous Mon, 11/24/2003 - 20:01

Hard to believe isn't it? I think in this case, though, truth is stranger than fiction, but perhaps it's understandable given the target audience for the thing.

Marketed as a guitar player singer-songwriter 12 track, digital equivalent of a fostex 4-track, who's gonna even think about external pres, right? Most of the guys with these are a make do with much less breed. non-engineer type musicans in other words, wanting to overdub some demo tracks, and then some, given the promise of digital (lotsa comping, etc).

Anyway, it's interesting to know that just going through the korg's pres will probably affect the signal chain regardless of the korg's trim setting, other than a hypothetical (and perceptively subjective) sweet spot that may exist for better linerarity).

If I crank out a few acoustic tracks over the next week, I'll post them anyway. thanks for the reply.

anonymous Sat, 12/20/2003 - 17:27

Gosh !
What a bummer. Sell That gadget and get something that you can at least explore the ins and outs.
I could not begin to acheive my sound with out my external pre-amps. I am still using black faced adats.
They have there weaknesses, but I have worked over many working parts and I beleieve that the orrigianl is still better sounding than the newwer. 60,000 strong and they are so so cheap now.

Tube-pre-amp to compressor to recorder. This works good for me 80% of the time. The tubes generate an even order harmonic that is unreplacable at Mix down/Mastering. It takes away from the digital perfectness. and with this, isn't this the whole point.
Bass and drums sound more real and more dynamic with the tube pre's. I never leave home with out them.
Gerald Cook
P.S.
Check out my new site http://www.artistrecording.com

sserendipity Fri, 01/23/2004 - 18:03

Originally posted by Kurt Foster:
Jon,
If you are using another pre amp, then why even pass the signal through the mackie on the way to the recorder? Bypass that mackie! Patch the output of the mic pre directly to the recorder. There is no sense in running the signal through 2 pre amps, or a mic pre and a line amp.

The reason I was thinking of piggy backing the two units was that I had a live jazz group to record, and wanted to set up monitor feeds without going through the pc first.

Thanks for all your help, Kurt and everyone else.

anonymous Thu, 01/29/2004 - 10:07

Originally posted by Kurt Foster:
I'm not questioning you but I find it difficult to understand why Korg would make a recorder that didn't have any line inputs??

This conversation interests me as well. I'm in the same boat with the Roland 2480. Not a single way to get an analog input into that thing without going through a Roland pre. Yup. Believe it (as stupid as it is). :p

I'm a slave to Roland pre's until I get an external A/D converter.

KurtFoster Thu, 01/29/2004 - 13:43

I have a friend whos son is setting up a small studio in their basement.. he has a Korg D1600 and I have been getting a chance to goof around with it a little... The owners manual states that the 1/4" inputs doubles both as a mic pre or a line input.. We plugged a VTB-1 into it and it was an improvment.. we had to keep the attenuator knob turned down all the way.. but it seems to work ok like that. I'm going to lend him an adat so he can use it for line inputs completly bypassing the line ins.. I'll post to let you know if that is an improvement.

Rod Gervais Thu, 01/29/2004 - 14:06

The reson Korg didn't design these systems with inserts is because they wanted to present it as a complete system - just take it and run.

So intead of inserts they set it up with an rather extensive set of built in "plug-in's".

I'm not defending the design - just explaining it.

Anything you run through any piece of gear - even in by-pass mode - effects the sound.

So the answer to your question is "yes".

The real question is - with the 2 put together - can you come up with a sound that works for you?

Rod

knightfly Fri, 01/30/2004 - 06:16

Quite a few consoles in the "pro-sumer" range seem to have this design flaw - more than one Tascam board I've seen prints on is this way. When you "switch an input to line in", even though there is an actual switch, all it does is to switch an attenuator into the chain. The sound STILL goes through the preamp circuitry, which practice never ceases to amaze me. A switch is (usually) almost as good as a straight wire, and either one beats the sox off ANY active circuit as far as accuracy goes.

The minute you change a signal, technically you've distorted it. Sometimes that's a GOOD thing, at least as far as subjective sound is concerned, but it's still a fact - change = distortion. (We're talking REAL world here, not theoretically perfect circuits that can (theoretically) make a signal "bigger" without changing its THD, IMD, phase, or any other characteristic.)

I say this not to incite a riot, but just to make a point. Every time I've looked at schematics of lower cost mixers, I've wondered why that stupid line/mic switch couldn't have been used to hardwire bypass all the crap instead of just changing the gain.

So if you go shopping for a "better" unit, be sure and look at the circuit diagram before assuming that those "line in" switches are really what they claim, instead of just a "gain change" that puts your signal through just as many extra components as always... Steve

PS - if you find one that isn't this way, please share the info -

KurtFoster Fri, 01/30/2004 - 13:31

Originally posted by Jonathan El-Bizri:
The reason I was thinking of piggy backing the two units was that I had a live jazz group to record, and wanted to set up monitor feeds without going through the pc first.

Thanks for all your help, Kurt and everyone else.

Jon,
Most mic pres will drive 2 line inputs without breaking a sweat, like one to the DAW and one to the monitor mixer. Many pro studios have areas of their patchbays dedicated to making splits or "mults".

By taking a 1/4" patchbay and configuring it as "non normaled" and running jumpers between the top row jacks (1 to 2, 3 to 4 etc) on the back side, you have a patch bay set up to do "mults". The top and bottom rows now form 4 paralled jacks, or a 1 into 3 "split".

Plug the out from the mic pre into the first jack, then one out from this to the DAW and a second out to the monitor system..