Orange to modern seems much louder (2 channel triple)

[Tone1026]

So i noticed tonight that for some reason, orange to modern is actually louder than red modern, settings being the same.. 9 oclock orange (to modern) = 10 oclock red....

Edit. the contrast comes more at 10 oclock orange where i have to be at a solid 11:00 red or so to match that volume. The orange volume pot seems a bit more agressive..

Orange seems also to have more gain, and more low end punch. I am aware of the prescence ddifference, but red seems to be weak in comparison to orange. i might measure the pots to see if there is a difference...

Could i have a weak cap on the red gain pot? Might that cause loss of volume and low end? I don't remeber anything in the manual about orange to modern being the loudest..

Thanks for your help guys.

 

[JCDenton6]

I'd ohm out the caps and the pots just to be on the safe side (pots should be 250k, 1nf caps)
Also ohm out the master pots (should be 1 meg)

IF everything measures out well, it may be some LDR's on the way out in the tone stack.

 

[Tone1026]

So it's not normal?

 

[Tone1026]

Well with the meter set at 2000k ohm the pots measured as follows:

volume: 563 orange, 551 red. (schematic for dual shows 1m doesn't it?) do you think 12k ohm difference would explain 1 hr difference in equal volumes?
prescense: 25 orange, 97 red (measuring this was a little tricky)
Bass: 557 orange, 549 red (interesting here that the bass pot value was higher for orange as well..)
mid: 26 orange, 24 red
treble: 218 orange, 214 red
gain: 250 orange, 256 red (schematic for dual shows 1m doesn't it?)

They all rolled up to their values, presence was trickier, im guessing because of the fancy circuitry..

heres the gain pots



They all look like the same manufacturer
here is the rest

 

[domct203]

You can not accurately measure pots while in the circuit. They need to be isolated (disconnected). There is more resistance in the circuit that will effect your readings.

Also, you can not measure caps with an ohm-meter.

I'd ohm out the caps and the pots just to be on the safe side (pots should be 250k, 1nf caps)
Also ohm out the master pots (should be 1 meg)

IF everything measures out well, it may be some LDR's on the way out in the tone stack.

Dom

 

[Tone1026]

You can not accurately measure pots while in the circuit. They need to be isolated (disconnected). There is more resistance in the circuit that will effect your readings.

I did not know that. TY. Does the same go for guitar pots w/ pickups hooked up?

Also, you can not measure caps with an ohm-meter.

I was going to wait till sunday on that until i had a capacitance meter on the caps.

 

[ryjan]

Just play the **** thing! :lol:
Seriously, you're really starting to pick the fly **** out of the pepper with this poor amp.

 

[Tone1026]

Sorry if I'm being annoying with my questions. I was wondering if I was being overly picky by even posting this, but it seemed unusual. I don't want to exasperate anyone.

 

[Shemham]

I wouldn't trust the 1Meg gain pots shown in the Dual Rectifier schematics although I known what schematic you're referring to. I've already seen few messages referring to Mesa statements stating that all Rectifier revisions share 250k gain pots. I guess this could only be confirmed by JCDenton6 or other folk who've directly confronted Mesa around these questions.

As already stated, you have to measure the pots when removed from the circuit board.

Other than that those readings fit into the tolerance of the pots.

 

[ryjan]

Sorry if I'm being annoying with my questions. I was wondering if I was being overly picky by even posting this, but it seemed unusual. I don't want to exasperate anyone.

No worries. There's always going to be anomalies and imperfections with musical instruments. You'll drive yourself crazy chasing them all down. :wink:

 

[JCDenton6]

I meant to type capacitance meter in my past post, I tend to post in a hurry, not proof reading and run out the door.

I'm going to test volumes tomorrow @ practice and get back to you, red modern should be slightly louder due to more mids and orange modern being more bassy and scooped with a liquid feel.

No prob on the questions, that's what were here for and how we learn about these amps!

 

[Tone1026]

I meant to type capacitance meter in my past post, I tend to post in a hurry, not proof reading and run out the door.

I'm going to test volumes tomorrow @ practice and get back to you, red modern should be slightly louder due to more mids and orange modern being more bassy and scooped with a liquid feel.

No prob on the questions, that's what were here for and how we learn about these amps!

Cool thanks man! Yeah I can definately hear the difference in voicing, but orange seems to be a solid "hour" louder at that range i mentioned. My settings set close to what is in the manual for "molten red". I have also tried dialing reds presence back to try and "match" orange presence..

 

[domct203]

One phone call to Mesa could end this autopsy and get you back to playing your guitar.

Dom

 

[Tone1026]

One phone call to Mesa could end this autopsy and get you back to playing your guitar.

Dom

Yup. Tien says that Orange channel has negative feedback in modern mode that red doesn't have. Giving it a more compressed feel. That may explain the extra low end punch. Maybe that explains the hour or two in volume difference..?

 

[YellowJacket]

You know, there is nothing wrong with using the orange channel for most of your playing. In my opinion, the orange channel is the 'secret weapon' of the old 2 channel heads!

 

[BrentSSL]

I have rackto that does this as well and I do agree it is the secret weapon of the old rectos on my old three channel I used to use channel two as more "rock" feel aka old school metallica and red for lets say rammstien heavy now on my rackto its the other way around. I get almost a mark series tone heavy from the red channel and a nic heavy bottom end punch from the oroange channel when its on modern I run them oth in modern I like red for leads too but I am more of a rythm guy