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ADA Preamps => Original MP-1 => Topic started by: Chip Roberts on July 13, 2017, 04:25:42 PM

Title: It's time to have "The Talk" (about gain stages)
Post by: Chip Roberts on July 13, 2017, 04:25:42 PM
Alright guys, thrill me!  I know nothing about this.  I guess the question behind my question is: if the manual for the MP1 states that the output should be set as low as possible, what does turning it up and down do?  When I crank it, just as an experiment, I get a horribly fizzy, yet satisfyingly saturated tone.  Normally I set the output on the MP1 between 6:30 and 9 o'clock, then tweak the actual output with the Midiverb. 

I know some of you have a doctorate in gain staging, so educate me! 
Title: Re: It's time to have "The Talk" (about gain stages)
Post by: Iperfungus on July 14, 2017, 01:55:54 AM
Uhm...I think a good starting point would be to know your settings...

I mean OD1, OD2, Master, EQ, Presence...

I found all these parameters have a strong interaction and all of them are involved in shaping the final sound/tone.
One of them could make another saturate making some stage/stages clip and add unwanted noise.
Then the Output Level sets the final volume (not the gain) of the signal you'll pass to your effects unit and/or power amp: if that signal is too high or too saturated, it will probably saturate inputs of the effects unit.

In my opinion, the best is:

1) shape your sound with ods, master and eq
2) set the output level

with any effects unit in bypass (directly to power amp).

Once you're satisfied, turn effects on and fine tune Input and Output levels of the unit, before power amp.

Among my patches, I've one with some high gain settings and that's my main reference:

OD1: 7.5
OD2: 7.5
Master: 5.5
Bass: 9
Mid: 6
High: 9
Presence: 12

Before the SS Ultra+ mod, with these settings I was used to keep Output Level pot at around 11-12 'o clock and then fine tune the output with the G Major (and its Input level as well), before the power amp, to have a good thick sound.

After mods, I found that I can decrease the Output Level on MP-1...since I got the same output at around 10 'o clock (I set it at little less than 11 'o clock now).
In any case, if you want to have a THICK signal coming from MP-1 outs, you've to set Output Level above 9 'o clock IMHO.
Otherwise the signal from MP-1 would be too "weak" and poor of frequencies/overtones...something you cannot recover by setting Input and Output levels on effects units.

About settings, since now the overall noise level has been strongly decreased by mods (there's just a little bit of swish with very high gain settings...that's normal...but no hum or buzz anymore), another thing I discovered is that I set Presence too high (12) and this added some "fizzy" noise to other noise.
Now that other noise is gone, I found that the "fizzy" noise comes from EQ (Presence, Highs) if I set OD1 and OD2 to high gain levels: if I decrease Presence to 10 the noise is almost gone...even if I set Output Level at 1-2 'o clock.
Then, if I reduce Highs a little...the "fizzy" noise goes lost forever.

I'm going to reshape the eq of my patches where OD1 and OD2 are set over 6.

In this way, I can get rid of noise...reshape my tone...and fine tune Output Level before the G Major.
Once there, I fine tune Input and Output levels...and the internal G Maj noise gate will do its job in easier way when I go higher gain on MP-1.

It works fine for me.
Title: Re: It's time to have "The Talk" (about gain stages)
Post by: rabidgerry on July 14, 2017, 07:21:47 AM
The simplest answer to this question is the output level controls the final volume of your MP1 into either your power amp or an FX unit in which case you set the volume at a setting that best accommodates the device it outputs to.

So adjust it were it's a decent amount, but healthily not near a point where it will clip going into either amp or FX unit.

And when I say clip, I mean clip from the amp/fx units input.

As Iperfungus:

1) shape your sound with ods, master and eq
2) set the output level

Turning this final output has no effect on the sound other than volume, it doesn't affect your tone.  It's simply there to amplify the tone generated by the other controls mentioned.

I have my output about 3-4 on one MP1 with MDRT in it, then on the non modded version the output is at around half way 5-6 because it's not as loud as the MDRT modded version.  I have my 3TM at about 3-4 also.

I have ever read the manual of the MP1, not fully anyways.