DC-5 tubes

[MusicManJP6]

Here's a goofy question since we were looking at schematics. It's an older version of the DC but the person I got it from only had the new version of the 2-button footswitch. It would change the channel used in that jack but won't do anything when I have it plugged into the back for the jack on the EQ/Rev. Is there a way to rewire that switch to convert it to the older footswitch?

This is the one I have http://mesa.stores.yahoo.net/fcdcn.html

This is the one I should have had. http://mesa.stores.yahoo.net/fcrg.html

Hmmm... so you are saying that the footswitch you have only changes amp channels (and does nothing when you hit the EQ button) when using the footswitch input on the front of the amp? If so there is a mod that Monsta-Tone (the resident DC guru/Mesa tech on the boards) knows how to mod the footswitch input on the front to operate like the newer DCs and make use of that EQ on/off button on your footswitch you currently have. Do you need to be able to turn the reverb on/off? If not then i'd mod the front input and forget about the switching on the back.

 

[MrMarkIII]

Hmmm... a gold pin ECC may be warmer, but prob has about the same gain - i'll have to try an AT7 in V4 and see what that does for the clean channel instead... I love having some different preamp tubes around to swap in and out!

ECC81 = 12AT7. Same tube.
Here's a list, because I'm too lazy to type it all out :
http://www.diyguitarist.com/GuitarAmps/SD-Convertible/patgf1.htm

 

[lockbody]

As several others have done, I run a NOS 5751 in V4 and love it. I do like my cleans a little "hairy" though and still run a ax7 in V1.

 

[Kage]

Here's a goofy question since we were looking at schematics. It's an older version of the DC but the person I got it from only had the new version of the 2-button footswitch. It would change the channel used in that jack but won't do anything when I have it plugged into the back for the jack on the EQ/Rev. Is there a way to rewire that switch to convert it to the older footswitch?

This is the one I have http://mesa.stores.yahoo.net/fcdcn.html

This is the one I should have had. http://mesa.stores.yahoo.net/fcrg.html

Hmmm... so you are saying that the footswitch you have only changes amp channels (and does nothing when you hit the EQ button) when using the footswitch input on the front of the amp? If so there is a mod that Monsta-Tone (the resident DC guru/Mesa tech on the boards) knows how to mod the footswitch input on the front to operate like the newer DCs and make use of that EQ on/off button on your footswitch you currently have. Do you need to be able to turn the reverb on/off? If not then i'd mod the front input and forget about the switching on the back.

Yeah, basically, but I would much rather modify the pedal than the amp.

 

[MusicManJP6]

Hmmm... a gold pin ECC may be warmer, but prob has about the same gain - i'll have to try an AT7 in V4 and see what that does for the clean channel instead... I love having some different preamp tubes around to swap in and out!

ECC81 = 12AT7. Same tube.
Here's a list, because I'm too lazy to type it all out :
http://www.diyguitarist.com/GuitarAmps/SD-Convertible/patgf1.htm

Oh... DOH! I was thinking of an ECC83... didn't realize the 81 was an AT7... Thanks for the info!

 

[Kage]

Hmmm... so you are saying that the footswitch you have only changes amp channels (and does nothing when you hit the EQ button) when using the footswitch input on the front of the amp? If so there is a mod that Monsta-Tone (the resident DC guru/Mesa tech on the boards) knows how to mod the footswitch input on the front to operate like the newer DCs and make use of that EQ on/off button on your footswitch you currently have. Do you need to be able to turn the reverb on/off? If not then i'd mod the front input and forget about the switching on the back.

Yeah, basically, but I would much rather modify the pedal than the amp.

You know, the more I think about this the more I'm warming up to your idea. I wanted to do the pedal as I'm chicken about messing with the amp myself. But that would leave me with two separate pedals while the mod to bring the EQ to the front would only be one pedal.

'Nother question. How much gain is this amp supposed to have? I'm not sure what I expected but I would have thought it'd have more than it does. What amps would y'all compare it to?

 

[MusicManJP6]

Hmmm... so you are saying that the footswitch you have only changes amp channels (and does nothing when you hit the EQ button) when using the footswitch input on the front of the amp? If so there is a mod that Monsta-Tone (the resident DC guru/Mesa tech on the boards) knows how to mod the footswitch input on the front to operate like the newer DCs and make use of that EQ on/off button on your footswitch you currently have. Do you need to be able to turn the reverb on/off? If not then i'd mod the front input and forget about the switching on the back.

Yeah, basically, but I would much rather modify the pedal than the amp.

You know, the more I think about this the more I'm warming up to your idea. I wanted to do the pedal as I'm chicken about messing with the amp myself. But that would leave me with two separate pedals while the mod to bring the EQ to the front would only be one pedal.

'Nother question. How much gain is this amp supposed to have? I'm not sure what I expected but I would have thought it'd have more than it does. What amps would y'all compare it to?

It should have plenty of gain for anything from classic rock all the way up to hard rock and on the verge of metal if you use high enough output humbuckers. Not like a Recto, but more like a Mark series amp. Can you record your amp and let us hear how much gain you have?

 

[Kage]

I didn't expect recto territory, but weren't the Marks considered "high" gain? I'll try a recording.

 

[MusicManJP6]

I didn't expect recto territory, but weren't the Marks considered "high" gain? I'll try a recording.

They are fairly high gain, but it is a different type of gain structure. They are not that saturated and have lots of clarity. Change out your V1 tube and see if that makes a difference. You might have a weak tube somewhere.

 

[MrMarkIII]

'Nother question. How much gain is this amp supposed to have? I'm not sure what I expected but I would have thought it'd have more than it does. What amps would y'all compare it to?

Name your favorite player. Trust me, he uses less gain than you think.

 

[edward]

I've posted this before in the past, but what the heck, here is my "recipe" again. FWIW, it took me some time and lots of A/B-ing back and forth to determine what I really wanted. I suggest anyone doing tube experimentation do the same. And try this over a few days. Ears will "burn out" really quickly when exposed to volume and highs. Rest, and then come back with fresh ears to make sure you really are hearing what you thought you heard. My final recipe for my DC5:

V1: NOS Mullard 12ax7
V2: TungSol RI 12ax7
V3: TungSol RI 12ax7
V4: NOS RCA 5751
V5: NOS RCA 12at7
V6: NOS RCA 12at7
Power: Svetlana "Winged-C"

FWIW, I do not play any shred or metal, but am more classic rock, contemp pop, as well as contemp church music. What I love about my tone as you "see" it is, in the Clean Channel, lovely, chimey cleans with some hair around the edges (I am rarely ever spanky clean, but that is as easy as a turn of the knob...and sounds great, as well). The bootm is large and focused, never flubby. The mids are defined and clear. The highs smooth and glassy while never harsh or unpleasant (zero icepick). In Lead Channel, there is still huge gain on tap (should I venture into EVH's Pretty Woman, or a ZZTop-style mid-saturation thickness); or even punk-ish pop is there. Just great tonal range, better than with 12ax7s across the board, IMHO, and with far better indiv note definition. Not to mention highs that are much smoother and never sharp or "pointy."

If it sounds like I am pleased, it is because I am. And as I had mentioned, I went back and forth with a variety of tubes, and over some time, also ignoring what was printed on the tube (you'll notice I settled on both NOS tubes as well as current-production Re-issues, of which the Tung-Sols really score, IMHO). I really tried to "keep it honest" as far too many get "sold" on using NOS or the priciest ones for "the best tone" ...trust your ears. There was a time where I thought I may sell my DC5 for a MkIV ...I will never make that mental blunder again!!


Oh, and as a side note FWIW, I have since gone to NOS Mullard CV4024 (which is a 12at7) in the PI slot and the V1 for my MKIII SimulClass. Similar net change: less OD saturation (while still plenty left on tap), and in exchange a smoother overall tone (especially when clean), with better note definition across the board (especially in the Lead), and much nicer highs ...especially as a MkIII is a very bright amp (can take your head clean off!!) by nature. If you do one change, start with a good 12at7 in the PI slot; this one tube swap alone will have the single biggest effect on tone and dynamics. The other tubes are incremental differences. Hope this helps you some

Edward

 

[Kage]

I didn't expect recto territory, but weren't the Marks considered "high" gain? I'll try a recording.

They are fairly high gain, but it is a different type of gain structure. They are not that saturated and have lots of clarity. Change out your V1 tube and see if that makes a difference. You might have a weak tube somewhere.

Eh, nevermind. It just didn't sound like I guess I expected, but today I spent some time with the manual and did some tweaks. That's more what I was expecting now and it may be getting a starting position. Wasn't the amount of gain, it was how I had it set up. Something still isn't right with that speaker, suspicion is a loose dust cover. Sounded really good through the 5150 cab. I'm not going to miss the Twin I traded for it at all. Oh, and also put a set of the Mesa power tubes in, I was suspicious of the JJ's. That in itself was a big improvement.

 

[Kage]

Heh, haven't posted about my DC-5 since it died out in practice two days after my last post here. Amp tech was backed up and didn't get to it until this past week. The Mesa tubes are dead, I think he said he had to replace the screen resistor. When he got it on the scope the sine wave only had the lower cup-shaped humps. I know what that looks like but I don't know what it means for the amp. The master volume was done too, had to be replaced. Apparently the rhythm channel actually gets clean now and he says it sounds amazing when it works. I guess now he's chasing down an intermittent problem it stops making any sound and just hums. This won't be cheap but I hope it's worth it. I wanna play it, dammit! :lol:

 

[MusicManJP6]

Heh, haven't posted about my DC-5 since it died out in practice two days after my last post here. Amp tech was backed up and didn't get to it until this past week. The Mesa tubes are dead, I think he said he had to replace the screen resistor. When he got it on the scope the sine wave only had the lower cup-shaped humps. I know what that looks like but I don't know what it means for the amp. The master volume was done too, had to be replaced. Apparently the rhythm channel actually gets clean now and he says it sounds amazing when it works. I guess now he's chasing down an intermittent problem it stops making any sound and just hums. This won't be cheap but I hope it's worth it. I wanna play it, dammit! :lol:

I'm sure he'll be able to track down the problem. Good luck!

 

[Kage]

Me again, still without my amp. From what I can gather, he says there is either a bad solder joint or a cracked trace. Anybody have any suggestions for where such a problem might most likely be hiding? From what I've been told it sounds great when it works but when it stops it just gives a loud humming sound. The tech has offered that I can pick it up any time and only pay for the new power tubes. His suggestion was to call Mesa, probably have to ship it to them. That's if he doesn't miraculously find it by the weekend.

 

[Kage]

Dropped it off at new tech today. Got to play around with it for a bit, the rhythm channel begins to break up past 1 on the gain and is significantly louder than the lead channel when the channel volumes are set the same. Loud hiss from it and it just doesn't sound "right" to my ears. And the treble control on the lead channel works backwards. How odd. Fingers crossed, this time it's at the local Boogie repair shop. Original tech replaced a pot (not the one that's backwards) and one of the big ceramic resistors. Screen, I believe. I played through both a Mark IV and an F100 this weekend and now I'm really antsy to get this thing fixed.