ADA Depot - A Forum To Support Users of ADA Amplification Gear

Let's Get Technical => All PREAMP Tech Tips & Support => Topic started by: trader144 on November 30, 2014, 06:12:11 PM

Title: Front Input level pot level
Post by: trader144 on November 30, 2014, 06:12:11 PM
After some experimentation, I thought this was worth a separate discussion.

I have always kept my input level between 10 and 3 o'clock typically at 12 as a standard.
Reasons:
1. ADA manual says to adjust it after you set your power amp to the proper volume.
2. Needed to park it in one spot so I can level each preset to the same output level for the sound guys.

Recently, I saw some of the veterans pics and they have their input level pot cranked.
So I tried it.

What I found:
1. Much more distortion at lower levels
2. It changed the character of the sound; less SRV-throaty and more focused on the highs.
3. The EQ seemed to act differently, as in the mids and lows were less responsive.

I looked at the schematics (tried).

Any thoughts on how the input volume pot interacts with the tubes? Does it drive an opamp?

Seems like you need to try all positions whenever you get a new tube/mod.

There are so many pieces to the tone puzzle.

David
Title: Re: Front Input level pot level
Post by: rnolan on December 01, 2014, 05:57:07 AM
Hey David, the possibilities are seemingly endless, MJMP has posted elsewhere here how the gain structure goes from MP1 input through SS opp amps to V1 circuit to V2 circuit and on to eq, loop, stereo chorus a/b outs. Obviously driving the input stage harder will raise gain in SS and V1 depending on voice.
ADA advice re proper volume.. set power amp to overall vol you want, adjust ADA vol to suit situation. My understanding was vol on mp1 was output level not input ??
Title: Re: Front Input level pot level
Post by: MarshallJMP on December 01, 2014, 01:43:24 PM
Well i found also that the front pot level changes the sound a bit if you turn it up,strange but it is.