DC-10 combo Master Volume problem.

[maarz12]

Hello everyone,
Hope someone can help me with this:
I own either a 97 or 98 DC-10 combo and after reading 'bout what a Master Volume (MV) is supposed to do, I belive my amp's MV is faulty. As I increase the the level of the MV the resulting effect is not louder but, spongier. It's wierd because the channels' volume pots make the amp louder not spongier like I thought. It's as if there is NO MV. That's it. If somebody out there knows what's up with my amp, please leave a message. Other than that, the amp sounds fantastic (distortion and tone wise)!
Thanks!

 

[Charles Reeder]

Hey maarz12:

It may be dangerous to 'assume' anything...but it sounds as if you have the identical problem with your DC-10 that I ONCE HAD with my DC-5.

It seems that Mesa DID USE the correct 'audio-taper' pot for the Master-Volume; BUT (for some unknown reason) installed a resister in parallel with the Master-Volume pot that cancels out the benefit of the audio-taper pot!

I wish I had the link: but if you 'scour' the past pages of the 'Boogie Forum Vintage pre-1991' amps; you should eventually find the one that addresses this issue. It even includes a shot or two of the inside of the chassis; and pinpoints the resistor that is at fault.

All you have to do is 'clip' the resistor out of the circuit. That's it...no soldering...or other parts needed. I did it to my DC-5 and it made a 'world of difference'.

If by any chance you can't find the posting I mentioned...then just re-post this thread on the 'Vintage Forum'. Someone will 'come-through' for you.

Best of luck: Charles

 

[edward]

Your Master Output knob should regulate the overall volume, period. If it's not doing this one basic task of adjusting volume, then there is something wrong.

That said, it is true that once you get the master output knob past 6 or so, there really isn't much of a diff in volume. BUT, that should be seriously LOUD at 6, unless your indiv channel volume masters are barely cracked open. While cutting the resistor mod improves the taper (and improves low volume tone, IMHO), you still may have a problem. How loud is your amp when you notice the master doesn't do anything? Where are your channel masters set? ...3 or higher?

Edward

 

[maarz12]

Hey maarz12:

It may be dangerous to 'assume' anything...but it sounds as if you have the identical problem with your DC-10 that I ONCE HAD with my DC-5.

It seems that Mesa DID USE the correct 'audio-taper' pot for the Master-Volume; BUT (for some unknown reason) installed a resister in parallel with the Master-Volume pot that cancels out the benefit of the audio-taper pot!

I wish I had the link: but if you 'scour' the past pages of the 'Boogie Forum Vintage pre-1991' amps; you should eventually find the one that addresses this issue. It even includes a shot or two of the inside of the chassis; and pinpoints the resistor that is at fault.

All you have to do is 'clip' the resistor out of the circuit. That's it...no soldering...or other parts needed. I did it to my DC-5 and it made a 'world of difference'.

If by any chance you can't find the posting I mentioned...then just re-post this thread on the 'Vintage Forum'. Someone will 'come-through' for you.

Best of luck: Charles

Thanks for the info, Charles!
I'm gonna scour about and find the info I need-Hopefully that'll be the issue.

 

[maarz12]

Your Master Output knob should regulate the overall volume, period. If it's not doing this one basic task of adjusting volume, then there is something wrong.

That said, it is true that once you get the master output knob past 6 or so, there really isn't much of a diff in volume. BUT, that should be seriously LOUD at 6, unless your indiv channel volume masters are barely cracked open. While cutting the resistor mod improves the taper (and improves low volume tone, IMHO), you still may have a problem. How loud is your amp when you notice the master doesn't do anything? Where are your channel masters set? ...3 or higher?

Edward

Hello Edward!
Thanks for your time in addressing my question.
To follow up:
For gigs I have my amp at half power (60w in this case) and have the Gain at 6 for Clean and 8 for Lead; Volume at 5-6 Clean and 4-5 Lead; Master set at 4 (starting points). That said, as I increase Master there is but a slight increase in volume but not like I thought it would be: an Obvious increase . It's more of a sponge like increase. That's about the only way to describe it. Now the volume pots for the channels: as I increase the level from their starting points there IS an obvious increase in perceived loudness. so there lies the problem.

 

[edward]

Your Master Output knob should regulate the overall volume, period. If it's not doing this one basic task of adjusting volume, then there is something wrong.

That said, it is true that once you get the master output knob past 6 or so, there really isn't much of a diff in volume. BUT, that should be seriously LOUD at 6, unless your indiv channel volume masters are barely cracked open. While cutting the resistor mod improves the taper (and improves low volume tone, IMHO), you still may have a problem. How loud is your amp when you notice the master doesn't do anything? Where are your channel masters set? ...3 or higher?

Edward

Hello Edward!
Thanks for your time in addressing my question.
To follow up:
For gigs I have my amp at half power (60w in this case) and have the Gain at 6 for Clean and 8 for Lead; Volume at 5-6 Clean and 4-5 Lead; Master set at 4 (starting points). That said, as I increase Master there is but a slight increase in volume but not like I thought it would be: an Obvious increase . It's more of a sponge like increase. That's about the only way to describe it. Now the volume pots for the channels: as I increase the level from their starting points there IS an obvious increase in perceived loudness. so there lies the problem.

Hi Mario,

OK, that does sound kind of normal. The taper on the output master (with the resistor) is pretty poor ...most "happens" at the low end of the knob. Past 6 not much happens, and your description of spongy sounds about right; not much diff in volume as much as there is in feel/dynamics.

With the resistor snipped, the lower end of the taper is MUCH better with less of a "hair trigger" sensitivity, and the low-vol tone seems better, to boot. But still not much more beyond 6-7. As you found out, more signif volume control is at the preamp masters. If you need more latitude, try bringing those up and use a starting point of 3 on your output master. Or even better, put that other pair of 6L6s to use and revel in the fullness that is boogie 100 watts!!

Edward

 

[maarz12]

Again, a big thanks Edward for your help. I'll definitely look into this and hopefully problem solved. Oh and yep -those 100w are sure tempting! :lol:

 

[danielg]

maarz...you must have an extremely loud drummer to turn the master to 6...I have never had to go past 4 with my dc10 combo and usually everyone complains that I am too loud

 

[maarz12]

maarz...you must have an extremely loud drummer to turn the master to 6...I have never had to go past 4 with my dc10 combo and usually everyone complains that I am too loud

LOL - I do have an extremely loud drummer - thank God for ear plugs! But, you know, it was not until 'bout 6 months ago that I noticed that I had to crank up the MV a little more than usual. I used to play the amp at 100w (people would tell me I was to loud, too.) & MV would be set at 'round 3-4. Now I play it at 60w (I like the "pushed" sound of it cranked) & have the MV at 4 starting point. Maybe new power tubes?
Thanks, danielg!

 

[edward]

maarz...you must have an extremely loud drummer to turn the master to 6...I have never had to go past 4 with my dc10 combo and usually everyone complains that I am too loud

LOL - I do have an extremely loud drummer - thank God for ear plugs! But, you know, it was not until 'bout 6 months ago that I noticed that I had to crank up the MV a little more than usual. I used to play the amp at 100w (people would tell me I was to loud, too.) & MV would be set at 'round 3-4. Now I play it at 60w (I like the "pushed" sound of it cranked) & have the MV at 4 starting point. Maybe new power tubes?
Thanks, danielg!

Hahaha I just posted a short while ago about how cool it was to gig outdoors (my first outdoor event), and how cool my DC5 sounded pushed! Joy joy joy!!! I think given what you just said here, keep pushing it at 60w if you dig the tone, and don't worry about where the knob is set. You've always got volume to spare in the channel masters (not to mention that lonely pair of cold tubes ). Enjoy!! ...though at that volume with a boog, I've come to find that smiles come involuntarily

Edward

 

[maarz12]

Right on, Edward! Pure Boogie joy!