Preamp bi-passing Q's

As most of you who have been following the saga know I have been using the ONYX1620 mixer.
To the me the pre’s on this unit are completely clinical and just sound too sterile to be musical, (especially when compared to recordings with Soundcraft pre’s I was using).

I now own a few rack mic pre’s (a Trident 4T, a Joe Meek VC3Q, a Sytek MPX-4Aii, and a RNP) but in using them I cannot help but think the Mackie is also imparting it’s pre (at a very low level) onto the signature of the track as well…which is why I am asking for advice on the best way to bypass the built in pre’s on the board.

It’s probably something simple and easy I am overlooking, but as it stands the gain on the Mackie channels has to be cracked just a tad for a signal to go through it regardless of how high I have the output on my rack pre’s driving in, like, should I be using a snake to convert the XLR out of the pre’s to 1/4 and going in the D/I’s or line ins/inserts on the board instead?

keep shinin

jerm :cool:

Are there no inserts on the Mackie?

Yeh - my thought also. A channel insert would bypass both the pre-amp and
the equalization of the channel strip. You should also be able to
bypass the fader as well (pre or post fade).

The 1620 has inserts for the first eight channels. Correct?

Seems to me there are modifications that can be made to Makie Pre-amp strips in their various mixer models to suit the owner/operator for either recording or sound reinforcement applications…
to make them user friendly…


If it were me I’d look into this with Makie Support… It might be a jumper wire modification on each strip…
or something like that…




Bill…

Quote: (sevenOfeleven @ Mar. 03 2010, 4:02 PM)

Yeh - my thought also. A channel insert would bypass both the pre-amp and
the equalization of the channel strip. You should also be able to
bypass the fader as well (pre or post fade).

The 1620 has inserts for the first eight channels. Correct?

Yes Tom and seven there are inserts, on the first 8,

however it was my understanding they were for adding FX into the chain (using what looks like a stereo plug, but Bubba explained to me is not stereo merely one signal being sent and one returning.) I think you have to leave a mono plug pulled out part of the way to only send a signal in so the second part of the sleeve does not connect.

How the mixer is set up now the faders and EQ's are bypassed, at least for the signal that goes out to the converters, but not the preamps to my knowledge, at least as I said I have to have them cracked ever so slightly or no signal get's through.

Wox, I am aware of the wiring modifications suggested in the Mackie forum to bypass the pre's but am real leery of doing anything like that to this board that if done incorrectly or getting a bad soldering joint could effect the signal chain later down the line leaving me high and dry at a time when I don't have time to fix it (like on stage).

Guys I am going to try sending the signal in the inserts and see if a signal goes through without the preamp on, will let ya'll know if it works.


keep shinin

jerm :cool:

On the insert
The TIP of the stereo plug is the SEND (you don’t need to use this)
The RING of the stereo plug is the RETURN


Quote:


I think you have to leave a mono plug pulled out part of the way to only send a signal in so the second part of the sleeve does not connect.


That is for tapping the output or SEND


(See page 20 of the 1620 user manual)

You want to use a stereo plug to do what you are talking about.

Inserts are cool. :laugh:

Hot :laugh:

Ice hot. :cool:

Quote: (sevenOfeleven @ Mar. 03 2010, 10:38 PM)

On the insert
The TIP of the stereo plug is the SEND (you don't need to use this)
The RING of the stereo plug is the RETURN


Quote:


I think you have to leave a mono plug pulled out part of the way to only send a signal in so the second part of the sleeve does not connect.


That is for tapping the output or SEND


(See page 20 of the 1620 user manual)

You want to use a stereo plug to do what you are talking about.

OK,

I have a stereo (looking) insert snake I will try it with that when I have time.

Thanx again guys!
:D simmer down.....

keep shinin

jerm :cool:

I finally had a chance to try it today with a mediocre buzzed jam, however it did not work (the inserts) they work for live broadcast on the ONYX but no signal went to the converters on the mixer and passed to the computer.
I ended up going in the line inputs on the channels without using any gain on the ONYX preamps.
I had to turn my Joe MEEK up to 65db to get a low level signal (luckily that thing is quiet so I was able to turn up the volume without too much hiss on the track later) and my Trident 4T (although it seemed to fair better as far as gain went much stronger signal)

The sample buzzed track below, Trident panned hard left, Joe Meek VC3Q panned hard right and a Aux signal off the Joe Meek dead sent through the Digitech S100 with reverb/delay dead center…so without further adieu it’s me LIVE in a cooper stooper!

Rising Sun

Mic’s used, Telefunckten M-80 (through the Joe Meek) and A Beyerdynamic MCE (N) though the Trident.

keep shinin

jerm :cool:

Well, could’ve done without the burp at the beginning. :laugh:

Sure you have those cables wired properly? I can’t imagine why it wouldn’t work.

Hey Jerm -
Nice job on that. You have a good voice.

Here is what I observed in CoolEdit.
Right Channel - guitar
Left Channel guitar (at a lower volume) plus voice.

The left channel seems to have an offset. That is the negative portion of
the wave data for the left channel is dipping farther (in db) than it’s
positive counterpart.
This tells me that somewhere in the left channel data signal path (a pre-amp
most likely) there is an input that is driven too hard.

Put it up in your editor (just look at the very last chord at the end of the
song) and you will see what I mean.

That is a form of distortion. If you can tame that with a lower input level,
then make up for the gain loss in your mix (how you do it is up to you) I think
you will be in great shape.

Hi jeremysdemo:

That file sounds great…
I downloaded and played it on-the-fly…
using Windows Media Player…
I may download it and open it in n-Track to see what it looks like there…


Gents…
Could it be that the Left Channel contains some DC Offset ????
making the wave file not Symmetrical ?







Bill…

[EDIT]

I downloaded and opened the file in n-Track… I see the the right channel is normalized at -5.51 db while the left channel is at -1.15 db or something like that… I re-normalized both channels to -1.24 db-or-so…

I also put the TomS request to zero db…

Sounds better now, TomS… :)

Thanks, Bill! :)

Hi jeremysdemo:

We’ve taken over your Rising Sun song and turned it into an Elvis Song…
:p
:laugh:
:)




OoHh…
I’ve been playing with that new Voice Plug that comes with b 2556 v6.0.9

Seems to work pretty nice…
at first glance…





Thank you Flavio…
:agree:










Bill…

Quote: (sevenOfeleven @ Mar. 13 2010, 9:15 AM)

Hey Jerm -
Nice job on that. You have a good voice.

Here is what I observed in CoolEdit.
Right Channel - guitar
Left Channel
guitar (at a lower volume) plus voice.

The left channel seems to have an offset. That is the negative portion of
the wave data for the left channel is dipping farther (in db) than it's
positive counterpart.
This tells me that somewhere in the left channel data signal path (a pre-amp
most likely) there is an input that is driven too hard.

Put it up in your editor (just look at the very last chord at the end of the
song) and you will see what I mean.

That is a form of distortion. If you can tame that with a lower input level,
then make up for the gain loss in your mix (how you do it is up to you) I think
you will be in great shape.

I am not real sure what is causing the guitar to be different on each channel in this mix, but it is even on both sides on the original track.
It is a tremolo FX out of the GNX4 but I only sent one side of the output to the mixer, so it is mono signal recorded onto two tracks.
However, this was recorded live so BOTH vocal mics have bleed from the guitar which was coming out the monitors as I played, since they are panned hard left and hard right that may be what is contributing to the guitar volume on both sides being different when it is heard alone.
The mic that went through the Trident was a Beyer condenser and the signal was quiet fat on the wav. form, that was panned left which did make that side louder.
Also both preamps have compressors on them and they were engaged so that too may have contributed to some sort of weird phase shift since they were set and operate differently.

In hindsight I should have used headphones instead of the monitors for the guitar, but it was a buzzed jam...and you aren't as sharp as you otherwise might be.

keep shinin

jerm :cool:
Quote: (TomS @ Mar. 13 2010, 6:36 AM)

Well, could've done without the burp at the beginning.
:laugh:

Sure you have those cables wired properly?
I can't imagine why it wouldn't work.

As I said it works fine for broadcast, in other words when sent into the inserts the signal comes out the main outs just fine, it just does not go through the channel to the converters.
Wox mentioned it earlier and it is true there is a MOD suggested at the Mackie site to fix this but I and leery of that.

PS the burp makes it an authentic Live jam, if I started editing it would not reflect a live performance.

keep shinin

jerm :cool:
Quote: (woxnerw @ Mar. 13 2010, 1:45 PM)

Hi jeremysdemo:

That file sounds great..

[EDIT]





I downloaded and opened the file in n-Track..
I see the the right channel is normalized at -5.51 db while the left channel is at -1.15 db
or something like that..
I re-normalized both channels to -1.24 db-or-so..





I also put the TomS request to
zero db..




Sounds better now, TomS..

:)

pretty sure the offset is difference of the preamps the Trident is much hotter signal than the Joe Meek.

If you would like I could give the unmixed files (3 vocal and one guitar) for you to mix as you please.

keep shinin

jerm :cool: