Optimizing my '85 Black Stripe w. 105 PT

[MonacoElite]

Hey guys,

Long time, first time! I thank you all in advance for your help.


I've come to own one of the original Mark-III's. The biggest selling point of this DRG was that it happened to feature the bigger 105 power transformer. Well, so far, so good. The amp sounds great...Strat with Antiquity single coils, Les Paul with PAFs, Ibanez with high-output DiMarzios...they each work well in their own domain.

So the next step is maximizing this amp's potential which means (A) new tubes, (B) servicing and maybe (C) modifications.

Here's the dilemma, I have a highly capable amp builder near me who quite happy to service the amp. Now, I'm thinking that if I asked him to do a couple simple mods, he'd happily do that as well so long as I knew precisely what I wanted done. I haven't spoken with him about this yet, but these are complicated amps so I don't want to wander in with "vague" tonal descriptions. Does that make sense? I want to save him the headache by having some idea what I'm going for.

I don't necessarily care about duplicating the C+ circuit just for the heck of it. I just want the amp to sound it's best. If I send this to Mike B. I would have to pay enormous shipping fees ($250) in addition to servicing and mod fees that could easily total $750 or more. Besides that being a little extreme, let's be real here, there's no need to bother the Master if there are simple things my local tech can do. Mike's a practical guy. He's not going to tell me to send the amp on a cross-country voyage just he can be the guy that changes filter caps. Mods? Maybe that's another story, but that's why I want to ask here first.

I know Mike isn't going to talk to me about the gritty details of these Mark-III mods. For one, those are company secrets. On top of that, we're worlds apart and he'd easily get over my head.


Okay, so with that said, are there any specific things that I could request of my local tech while he's checking the filter caps and whatnot that would semi-replicate the C+ mod's tonal effect? In particular I'd be wanting to take out some high-end harshness or "fizz." To me, that would be 90% of it, I think. That's gotta pretty simple, right? Surely a local tech could handle that?


Oh, and would it be difficult for someone with competent skills to replicate the Vol-1 mod wherein you have separate control over the rhy and lead input gain settings? Gosh, that'd be such a nice thing to have! Is there anyone who wouldn't want that, haha?


Ok, that's it for now. Any thoughts are welcome.

 

[s-fresh]

When you say cross country I assume you are in the US? You can ship just the chassis to Mesa for a lot less than $250! You're not wrong about the service though. I had my 105PT Mark III upgraded with everything other than ++ at Mesa and it ended up being a lot even without shipping. Personally I think it is worth it to have a completely refurbished amp from one of the people that originally built it. We are really spoiled to have Mike still working on these after so many years. I know not everyone thinks this way, but having Mike do the work also helps maintain the resale value.

 

[MonacoElite]

When you say cross country I assume you are in the US? You can ship just the chassis to Mesa for a lot less than $250! You're not wrong about the service though. I had my 105PT Mark III upgraded with everything other than ++ at Mesa and it ended up being a lot even without shipping. Personally I think it is worth it to have a completely refurbished amp from one of the people that originally built it. We are really spoiled to have Mike still working on these after so many years. I know not everyone thinks this way, but having Mike do the work also helps maintain the resale value.

I'm on the east coast so shipping rates are around $100 (each way). So $250 probably ain't far off once packaging in included. I'm estimating shipping ($250), tubes ($200), servicing ($200) and any potential mods ($200). As you can see, the costs really skyrocket.

That said, I simply have a lot invested in this amp already. I may have over-extended myself a bit in securing this. If I were to shell out $800 to have Mike B. perform the work, there's no doubt I'd have $2k invested in this amp. Suffice it to say, the amp is what it is. It's a Mark-III. No matter how cool it is to the owner, the resale value is not going to approach $2k.

So I'm resigned to the fact that whatever I do is coming out of my pocket and will have to be for my own personal enjoyment. Even a C+ mod isn't going to change that. Don't think I'm poo-pooing the idea either. I had a red stripe I got rid of in order to acquire this. I've long researched and pondered these mods.


I just want to know if there's something simple I can get done on my end. Mike B. is a great guy, but he's also busy. And both he and my local guy "deserve" to be in business, right? Let's put it this way, I'm not the type of person that automatically values nostalgia over local small business. I'm happy to let my local tech change caps. The question is...can he do more than that without being the guru that Mike B is?


I'm trying to be practical here. I don't mean to imply by any stretch that I wouldn't absolutely prefer Mike B to get his hands on this if it were more reasonable but I definitely don't want to be the ***** who invested $2,500 into a Mark-III, you know? So that's why it's worth asking. If I were in CA, I wouldn't hesitate to bite the bullet. Sadly, I'm not. I do however have a very well qualified amp builder just next door.



Btw, how much change did you notice in the lead channel? I'm a JP disciple so I'd love it to be smoother than it is. Right now, mine is quite bright. That's great for the Fender-y clean but it takes away from the lead channel when you're pushing into Hetfield/Petrucci territory, I think.

 

[MonacoElite]

Oh, and for anyone who might care for history's sake this is # 15,4xx and is marked with a vertical black line.

 

[s-fresh]

It's obviously your choice and all of that. If it were me, that's already the best Mark III to start with, I wouldn't cut corners now.

FYI, it was a hardwood head, but I sold a fully serviced Mark III+/IIIC+ for $2,100 not long ago. No 105PT either. People will pay a premium for clean amps that have been recently serviced by Mike.

Also, with a UPS account I have shipped a full Mark III hardwood combo with 15" EVM (100+ pounds!) from Boston to California for only $110. You should be able to do a plain chassis for much less. That being said, I think your numbers are a bit low for for the service and mods so $800 total isn't out of the question. FYI, with the early ones the R2 volume mod is more work than later models so the upgrades can add up. A local amp tech isn't going to be aware of all the weird little details.

I don't think there is anything wrong with a local tech trying to get some work, but this is the Boogie Board where many people pray at the alter of Mike B. You've got to expect people here to recommend the most knowledgeable guy do the work while he is still willing to do it.

 

[MonacoElite]

Well, thank you for that news, s-fresh! Mine is presently sitting inside wood/wicker shell I had on hand. I really thought I was dead in the water with what I paid. I paid $1,400 for this in it's original black head cab. I felt like this was my one chance to grab a 105PT considering I'll probably never get to own a real C+.

Now, had I paid $800 or something and gotten a great deal, I'd be much more agreeable to sending this in, but man, the idea of having a $2k Mk-III is really making me nervous. I actually threw this up on Ebay recently after having a sort of crisis moment about this very topic. I wa getting so bummed out I just kind of wanted out of it altogether. Well, for better or worse it didn't sell. I was asking $1,500 with the wood/wicker head cab.

So here I am with an amp that maybe worth $1,400 if the right buyer comes along. The idea of sinking $800 more into it now is really scary--especially when I will ultimately come away with the same amp.


Anyhow, the only mod I would really be serious about is the C+ mod and that's because (as we all know) virtually every Mk-III is grainier and harsher than we'd like. So this morning I started thinking, why not just have my local tech do the servicing and while he's got it...why not see if there's a resistor or cap he could swap out that would take away some of the unwanted high end of this amp?

That would be so much more practical considering my situation, although I do agree...there's a little devil on my shoulder saying...'you know, if you just went all the way this might be the coolest Mk-III anyone ever owned...EVER!'

 

[modder]

For what it's worth between a few of us on here and Mike B we've basically figured out how to do the III+ mod. It's a pretty involved process, but you can simplify it somewhat too. Check the Mark subforum on this site, there's quite a bit of discussion about it.

If you want it to be smoother, the IIC+/III+ mod would definitely get you there. JRB on this forum recently did the complete conversion to IIC+ specs himself. Shoot him a message. His is a Black Stripe. I've had half the mod done and will be soon be getting the rest done to a Blue Stripe 60W by a local tech. It's totally doable.

 

[MonacoElite]

For what it's worth between a few of us on here and Mike B we've basically figured out how to do the III+ mod. It's a pretty involved process, but you can simplify it somewhat too. Check the Mark subforum on this site, there's quite a bit of discussion about it.

If you want it to be smoother, the IIC+/III+ mod would definitely get you there. JRB on this forum recently did the complete conversion to IIC+ specs himself. Shoot him a message. His is a Black Stripe. I've had half the mod done and will be soon be getting the rest done to a Blue Stripe 60W by a local tech. It's totally doable.

Thanks, will do!

...and yeah, sorry, I didn't know there was an entire sub-forum for the Mark series until 10 minutes ago, LOL.


Also, do you know if the Vol-1 mod is easy? I would imagine it is but I have no clue. It seems like splitting the input controls for Rhy-Vol and Lead-Vol wouldn't take much.

 

[xdg999]

I recently had Mike B. do the lll+ to my Mark lll Black Stripe with the x101 transformer. The lll+ mod is $200 paid directly to Mike B. and includes the R2 mod. New caps, pilot light, service and return shipping was $336. Shipping from Chicago to Petaluma was around $140. I also have a Mark lll Black Dot on the way that was just at Mesa for service and lll+ mod. This time it was $363 + $200 for Mike B. I currently own 6 c+’s and just bought #7. I’ll put the Mark lll+ Black Stripe up against any of my c+’s. It’s just as good. I can’t wait to see how the Black Dot turned out. It sounded awesome before I sent back. Mike B. knows these amps like no one else. I think it’s worth the extra money to have him work on them.

 

[Boogiebabies]

Well you sure the hell will not get any sag with the 105 at 505V DC under load. The exports and 60W were 448V under load and are less harsh.
An older 100 or something in the 460V range is more musical unless you are using Drop C.

Best C+ I ever heard was a IIB Export PCB upgrade to IIC+. 440V on the plates and 20uf Sprague cathode caps across the board.

If there are any Green Mexican ceramic disc caps, get rid of them. Uber harsh.

 

[woodbutcher65]

What's the opinion regarding the export transformer in a black stripe export model? Because that's what my Mark III is.

 

[Wizard of Ozz]

What's the opinion regarding the export transformer in a black stripe export model? Because that's what my Mark III is.

Depends on how much rust is on it. The Exp is cool, but I like them all. :mrgreen:

 

[Wizard of Ozz]

Well you sure the hell will not get any sag with the 105 at 505V DC under load. The exports and 60W were 448V under load and are less harsh.
An older 100 or something in the 460V range is more musical unless you are using Drop C.

Best C+ I ever heard was a IIB Export PCB upgrade to IIC+. 440V on the plates and 20uf Sprague cathode caps across the board.

If there are any Green Mexican ceramic disc caps, get rid of them. Uber harsh.

Although the 105P puts out a higher PV... the total wattage (75W) and headroom (DualClass) is reduced unless it is a HRG (which is somewhat rare... a HRG with 105PT). I’ve found the standard MKIII transformer in the Red-Green to be actually tighter sounding with addition of a pentode/triode switch mod... not needed in the Green. Not sure if the tighter sound (less round, smooth, warm sound) has more to do with the transformer or the overall wattage and headroom. Or to what degree of each.

Your thoughts?

 

[MonacoElite]

I recently had Mike B. do the lll+ to my Mark lll Black Stripe with the x101 transformer. The lll+ mod is $200 paid directly to Mike B. and includes the R2 mod. New caps, pilot light, service and return shipping was $336. Shipping from Chicago to Petaluma was around $140. I also have a Mark lll Black Dot on the way that was just at Mesa for service and lll+ mod. This time it was $363 + $200 for Mike B. I currently own 6 c+’s and just bought #7. I’ll put the Mark lll+ Black Stripe up against any of my c+’s. It’s just as good. I can’t wait to see how the Black Dot turned out. It sounded awesome before I sent back. Mike B. knows these amps like no one else. I think it’s worth the extra money to have him work on them.

Yeah, I was just reading through the big thread in the Mark sub-forum yesterday in which you were raving about how well your first one turned out. Congrats on that! If I'm not mistaken, the one you just sent off actually has a 105-PT, correct?

You may actually get that second one back before I make a move on mine so maybe you can update me on how it ends up and whether the 105-PT still comes through in an obvious way.

In chatting with Mike B yesterday evening, he reported that he was backed up and that he really wouldn't recommend sending anything in for at least a month. So I guess I've got some time to think this stuff over.

 

[MonacoElite]

I also inquired about the Vol-1 mod in which the input gains for the Rhy and Lead are separated via the introduction of a 'new' circuit that Mike B adds in and a small knob on the front (in place of the footswitch jack). According to Mike that's a bit of a pain but it's do-able and he said he'd charge about $250 for that if I really wanted it. It's hard to imagine not doing that because of the practical value it adds.

So I'm looking at:
$200 - Shipping
$200 - Servicing
$150 - Tubes
$200 - III+ / R2 Mod
$250 - Vol-1 Mod

$1,000 definitely makes you pause, being that it's nearly the price of the amp itself, haha.


I guess the alternative would be to have it re-tubed and serviced here locally which I'm guessing would not exceed $350, but I would like to at least experience the III+ mod so I think I'll commit to it at some point.

The amp definitely needs to be serviced asap, so I guess I'll have that done locally first. That way I can compare the amp as it has been to itself in a 'healthier' state. Once I do that, I can wait a month or two and then send it in.



Do you all have a recommendation on tubes beyond spending a fortune on vintage Sylvanias? What's the consensus among new options?

 

[MonacoElite]

Also, can someone shed some perspective on this matter I was discussing with Mike B. I just want to make sure I'm understanding things correctly.


#1
In chatting with him it sounds like there are fundamentally 2 types of original IIC+ amps. There are bright ones and non-bright ones. Mike seems to think that most folks want the non-bright sound. He said that he can tailor the III+ mod to mimic either.

Any comment from folks on that?


#2
If I'm correct, actual C+'s sometimes have the '++' mod. This seems to equate to more gain and some additional trimming to the bass frequencies. As Reza's video demonstrates, they can sound absolutely ripping and really quite modern. This mod seems to be oriented towards de-tuned stuff and I think some folks were evening discussing whether that might've had something to do with the evolution of the JP-2C "shred" mode which I know John uses most for his 7-string material where he wants a little tighter low end and a bit more saturation.

In reading jrb32's posts it sounds like he modded his black stripe with both '+' and '++' modes and even made the two available via toggle. I also read that Mike had accomplished something similar on a couple amps somewhere along the line but prefers not to do it now as it requires substantial reconstruction of the boards or something to that effect.

Anyhow, I asked Mike about this '+' versus '++' but I kind of got turned around. First, Mike obviously isn't the biggest fan of high gain so his descriptions of the '++' mod aren't always as "supportive" as you'd imagine.

But the way Mike described it to me was that once you've gone into '++' territory with the mod, there's really no going back. He made it sound like you can't really have both.

But it does at least sound like you could pick either the '+' or the '++' sounds when doing the III+ mod. Does that jive with people's understanding of things?




So it sure sounds to me like there are a couple of decisions you have to make before sending the amp in. Namely, do you want it bright or non-bright and do you want '+' or '++.'

This is kind of confusing though because when people describe sending their amps in, they almost always neglect to mention this stuff. It's all just rolled into the 'III+' mod as if to say all those mods are the same. Well, it surely doesn't sound like they're all the same, does it?

It appears to me like these III+ mods are a function of a couple parameters that come down to personal preference.



Many thanks!

 

[xdg999]

I had Mike B. reduce the brightness on the Mark lll’s like the HR c+’s. Before the mod I set the presence at 0-2. Now I can set it at 5-6. I use Chinese Military Beijing 12ax7’s in all of my Mesa’s and Sovtek 5881’s in all of my simul amps and most of my c+’s. This tube combination along with an MS-12 speaker is probably my favorite setup. The tone is really thick and touch sensitive.

 

[MonacoElite]

I started a thread in the Mark forum, but I'll just throw this here for simplicity...


I've heard folks promote these 105 power transformers like they're important, but it seems like from my admittedly very basic understanding, they aren't really optimal.

Based on what I'm told, these bigger 105 transformers run a higher voltage across the plates of the tubes which necessitates a lower grid bias. This lower bias essentially pulls the intended Class-A operation (~50% idle) towards Class-AB operation (~10% idle). I don't know how close it gets to Class-AB. Maybe someone can elaborate?

Anyhow, it seems to me that if someone really wanted Simul-Class, they ought to prefer the Simul-Class transformers with their lower voltages. That would be easier on the power tubes and allow true Class-A operation (which is the goal of Simul-Class). If on the other hand someone didn't like the idea of introducing Class-A, they'd be better off with with a standard 100w or 60w (non-Simul) model.

It seems to me that based on what I'm learning, my Mark-III DRG with its 105 is sort of "in the middle." I guess it's a "sort-of-Simul-Class" amp.


So, I don't get the hype of the 105 transformer. It's not maximizing any particular function. What is it specifically doing that makes it desirable?


And yes, I get that it's a way to associate your amp more closely with the IIC+ amps, but it's got to be more than that.

 

[MonacoElite]

I had Mike B. reduce the brightness on the Mark lll’s like the HR c+’s. Before the mod I set the presence at 0-2. Now I can set it at 5-6. I use Chinese Military Beijing 12ax7’s in all of my Mesa’s and Sovtek 5881’s in all of my simul amps and most of my c+’s. This tube combination along with an MS-12 speaker is probably my favorite setup. The tone is really thick and touch sensitive.

So did he talk to you about "bright" and "not-so-bright" IIC+'s?

Did he imply there were any alternative 'flavors' of his III+ mod (i.e. III++)?

Thanks for the tube advice. Share a link if there's a good source. It seems like 75% of what's out there are matched JJ's.

 

[xdg999]

The bright reduction mod makes the amp like a 100 watt c+. My simul c+’s are really bright which makes the cleans very detailed but can make the overdrive grainy. My Mark lll with the 105 was a beast before I sent it to Mesa. It was a lot tighter and more aggressive than any of my c+’s. I almost didn’t want to mod it. It’s waiting to be picked up at a UPS store. Unfortunately I’m out of town for work until Friday night. The 105 HR c+s are bold and tight. The 105 DR is softer and looser. If I had to choose one amp to play the rest of my life it would be my upgrade HR c+ with the 100 transformer in a combo with an MS-12 speaker. It has the best overall tone for my style of playing. I bought enough of the Chinese 12ax7’s years ago to last me the rest of my playing days. I don’t know where to find any now.