DG Custom 30 amp disappointments

[psamm]

I bought a DG Custom 30 amp new in 2019 from a well known dealer. The amp was manufactured in 2015 however, but I got a great clearance price.

I've never bonded with the amp and I so want to. It's just meh. There are hints of what I believe I know about the DG 30 from tons of YouTube DG live performances, but it never settles into a remotely inspiring tone, and I use a PRS DGT core guitar, among others. To top that off, I experience ghost notes at a level that makes me borderline crazy. Different levels and relationships of channel and master volumes or EQ don't significantly affect the ghosting. I've tried multiple sets of preamp, rectifier and power tubes hoping for a fix. I have some experience with VOX-based amps (DC-30, Hot Cat 30r) so I think my expectations are calibrated.

I communicated with support about it and furnished a couple of sound clips. To their credit, they offered to take a look at the amp for defects under warranty - but that meant cross-country shipping for me. It eventually boiled down to, "this amp is designed precisely for Dave and this is the way he wanted it." I really didn't think the warranty step was going to yield a meaningful outcome. My first mistake.

I've read about the history/causes of ghost notes and realize some amount of ghosting may be preferred by some players. I believe my situation is far more extreme than a touch or flavor of ghost notes. They're almost 50% as loud as the fundamental notes depending on the frequency played and how it relates to the presumed excessive 120Hz ripple that's likely present.

Because the chassis is unusually mounted, I was lazy and never pulled the amp to take a look. My second mistake.

I'm an amp and pedal kit builder and always want to examine what I bought - except this time. I finally yanked it and checked the filter caps and electrolytics around the power tubes. I checked the choke for inductance with an LCR meter ~20mH and normal for a vox-style amp I believe. Nothing's obviously out of whack.

Idly staring at the circuit in frustration I realized that many of the solder joints on the main board looked really poor. To some they might appear okay, but for a $3.5k+ boutique amp - no, they're not. Some of my favorite fastidious YouTube amp technicians would throw a fit if this hit their benches. It got me wondering if an excess of borderline solder joints could be causing the marginal performance I seem to be getting out of the amp.

As I'm now out of warranty I'm going to reflow the joints I can get to, and I've got to believe it's going to make a difference. It may help tone, it may help the ghost notes. I thought to get some outside opinions before I take that step and posting a few gut shots. Quality's not perfect but I hope you'll get the idea.

https://flic.kr/p/2qRQssz

https://flic.kr/p/2qRKVPz

https://flic.kr/p/2qRSn81

 

[Rider1260]

Even if you think you are out of warranty with PRS that is often not the case.
I have had great success on both the guitar and amp front sending " out of warranty " product back to PRS
and on both occasions I was 100% satisfied.
Just Saying.
I have also heard some amp owners got Doug S to mod amps to there liking

 

[psamm]

Even if you think you are out of warranty with PRS that is often not the case.
I have had great success on both the guitar and amp front sending " out of warranty " product back to PRS
and on both occasions I was 100% satisfied.
Just Saying.
I have also heard some amp owners got Doug S to mod amps to there liking

Thanks very much for this info. It was for exactly this reason that I thought to publicize my issues. I was definitely in an emotional space that kept me from considering that PRS Support may still be willing and able to help. With most companies, once the warranty period is over, we're strictly on our own.

I'll reach out to them as I'd corresponded previously regarding this amp.

 

[László]

I have one of the amps made for PRS' introduction at the Fall, 2013 PRS Experience event that I bought in 2014. I love it, and have used it in my ad music work for happy clients for over a decade.

I don't experience ghosting, and haven't had an issue with it. Maybe there's something wrong with that one that can be figured out and corrected.

One thing about the amp is that it isn't a Vox style amp like the Matchlesses, Bad Cats, etc (I've had them too), despite the designation of it being an EL84 amp.

The amp has a combination of Tweed lineage, a Hiwatt style tone stack, and a little Vox thrown in that frankly, I don't even notice. It's got way more bottom than any Vox, and the tone stack is definitely a different beast.

The output tubes are EL84Ms; they're different from EL84s - EL84Ms are designed to last 50,000 hours because they were created for use in Russian aircraft. I've had the same output tubes in my amp the entire time I've owned it. I bought a spare NOS set that I keep around for emergencies, but haven't had one yet.

They're also called 7189s; the Russian designation is 6P14P-EV. Apparently the 'EV' is an important part of the nomenclature as it has something to do with the construction of the tubes.

You've probably already checked this, but since the amp sat for years at a dealer's, you might want to make sure it has the correct tubes.

Doug Sewell told me in 2015 that the amp generates enough juice to melt standard EL84s.

 

[psamm]

@László
I really appreciate your thoughts about the amp. I guess I considered it a Vox-style amp based on the power section and features like the top cut -but was sure hoping with all its other classic amp influences it would slot in nicely to my collection. It wasn't right for me to categorize it quite the way I did. I'm familiar with a lot of DG's live performances with the amp - mine sounds like a poor imitation.

Luckily I've got some history with EL84Ms/6P14P-EV tubes. Back in ~2010 I bought a quad of 6P14P-EVs from an Ebay seller in Ukraine for my DC-30 because of their ability to handle extra power. I think they were $30 for the set - man if I knew then what I know now I would have bought a case. Where'd you get your NOS sets?

I thought tubes were the first logical problem and tried new Sovtek EL84Ms and my known and tested 6P14P-EVs. (Because of the amp's fans and the manual's details about power tube replacements I knew better than to sub anything else.)

Just getting confirmation from an owner of a DG-30 from the same approximate era that ghosting isn't an issue is strong encouragement for me to follow through. I was more than half convinced that really obvious note ghosting was a feature, not a flaw.

I suspect all of the questionable solder joints throughout the amp are the problem. Further examination showed several ground points to the chassis are also partially/cold soldered, besides all the other issues I see on the main board.

I think it's important to say that I'd buy another PRS amp without hesitation. Even the best manufacturing processes have a tiny percentage of QC issues, and some inevitably slip through to the end user. My amp certainly 'works.' It powers up and functions. The problems with it are subtle and on a factory floor or in a demo area were probably not obvious to a final tester - and the issues may have worsened over time before I finally bought it. Somebody's got to be that 1% statistic; it was just my turn. (The many dubious solder joints -could- have been caught visually however.)

My plan is to reach out to support and make my case based on the input I've received here so far. I'm grateful for the help.

 

[ruger9]

One thing about the amp is that it isn't a Vox style amp like the Matchlesses, Bad Cats, etc (I've had them too), despite the designation of it being an EL84 amp.

The amp has a combination of Tweed lineage, a Hiwatt style tone stack, and a little Vox thrown in that frankly, I don't even notice. It's got way more bottom than any Vox, and the tone stack is definitely a different beast.

Bad Cats have had so many models through the years, not all of them are even "Vox like" anymore. Current owner John Bingham has pushed the sound more Marshall in recent years (better than Marshall tho). My Hot Cat has EL34s and doesn't sound anything like a Vox. But yes- Vox is the "heritage" of the Matchless/Bad Cat/Sampson amp brands.

The new Bad Cat Cub V comes with either EL84s or EL34s, and I think they have one model than comes with 6L6s now...

 

[Mentalo87]

Perfect example why PCB isn’t bad or inferior to handwired stuff.

 

[ruger9]

Perfect example why PCB isn’t bad or inferior to handwired stuff.

The only way PCB is "inferior" is that it's more difficult for a novice to repair (solder) themselves. If I was a touring musician, I would prefer handwired for that reason alone. But otherwise, no: PCB is not inferior.

 

[László]

Bad Cats have had so many models through the years, not all of them are even "Vox like" anymore. Current owner John Bingham has pushed the sound more Marshall in recent years (better than Marshall tho). My Hot Cat has EL34s and doesn't sound anything like a Vox. But yes- Vox is the "heritage" of the Matchless/Bad Cat/Sampson amp brands.

The new Bad Cat Cub V comes with either EL84s or EL34s, and I think they have one model than comes with 6L6s now...

I had a Hot Cat. It's a lot more Vox in the preamp section than the DG30 but the Hot Cat has more bottom end than a Vox, as apparently the bottom isn't filtered out as much in order to make the amp louder (as in a Vox, bottom end making amps work harder and needing more power).

The Hot Cat is a terrific amp - at least it was in the previous iteration. I think Bad Cat has changed their manufacturing and design since hiring a new designer, and they may have gone over to PCBs.

 

[László]

The only way PCB is "inferior" is that it's more difficult for a novice to repair (solder) themselves. If I was a touring musician, I would prefer handwired for that reason alone. But otherwise, no: PCB is not inferior.

It's not inferior, but it is a little different sounding.

In a video interview a few years back, even Mesa's Randall Smith conceded that there is a difference in sound between PCB and hand-wired; he said he prefers PCBs only because they're more consistent from amp to amp.

Though I would guess that most amp manufacturers use PCBs because PCB amps are cheaper to manufacture in quantity than hand wired amps.

I find that hand wired amps sound more transparent and open. That doesn't mean 'better'; Mesas are less transparent than my hand wired amps, but they do a thing hand wired amps don't do.

I create music for a living and spend my life in the studio. I report only on what I hear myself.

I realize that everyone has different opinions on this stuff, and that's fine. I get what I get - I use both hand wired and circuit board amps - either can be great - and I don't object to anyone else's choices. YMMV

 

[Prina]

Agreed that those aren't great looking solder joints, so reflowing may help.

I'll guess that they're not eutectic solder.

 

[DreamTheaterRules]

Agreed that those aren't great looking solder joints, so reflowing may help.

To the point where it makes me curious... we haven't seen this before in a CAD amp. There are known incidents in the past where a vendor got bad solder that took a few years but oxidized and looked weird and bubbly like that does. It would IMO be unprecedented for PRS CAD amp to have more than one or two joints like that in the same amp unless it was potentially related to something like a bad batch of solder.

I could be wrong of course, but we haven't seen a CAD amp with even a few solder joints like that.

 

[ruger9]

I had a Hot Cat. It's a lot more Vox in the preamp section than the DG30 but the Hot Cat has more bottom end than a Vox, as apparently the bottom isn't filtered out as much in order to make the amp louder (as in a Vox, bottom end making amps work harder and needing more power).

The Hot Cat is a terrific amp - at least it was in the previous iteration. I think Bad Cat has changed their manufacturing and design since hiring a new designer, and they may have gone over to PCBs.

Well, a couple years ago the did a series called the USA Players Series, which was "military grade" PCBs. That's what I have. They also had their "Legacy" handwired amps. I think they have gone back to exclusively handwired again. They even had Mark Sampson come back (who recently passed away, RIP) the original Matchless founder (then later, Bad Cat founder). They currently are selling a design of his called the "Era". It also comes in a choice of EL84s or EL34s for different wattages. I don't think they are doing PCBs anymore.

That's my only gripe with Bad Cat: when John Bingham took over, they wouldn't leave well enough alone. Every years or two everything changed in one way or another. So saying "I have a Cub" or "I have a Hot Cat" doesn't really mean anything anymore, as it depends on WHICH one you have.

 

[László]

Well, a couple years ago the did a series called the USA Players Series, which was "military grade" PCBs. That's what I have. They also had their "Legacy" handwired amps. I think they have gone back to exclusively handwired again. They even had Mark Sampson come back (who recently passed away, RIP) the original Matchless founder (then later, Bad Cat founder). They currently are selling a design of his called the "Era". It also comes in a choice of EL84s or EL34s for different wattages. I don't think they are doing PCBs anymore.

That's my only gripe with Bad Cat: when John Bingham took over, they wouldn't leave well enough alone. Every years or two everything changed in one way or another. So saying "I have a Cub" or "I have a Hot Cat" doesn't really mean anything anymore, as it depends on WHICH one you have.

Mine was an early '00s version. I sold it to get a Two-Rock a couple of years later.

I was into the Two-Rocks for a long time, and had 5 or 6 of them; but the Hot Cat was also a great amp, and it's one of those amps I kinda wish I'd kept along with the T-Rs.

My guess is the difference between the circuit board and hand-wired versions would be very subtle. I wouldn't turn my nose up at a circuit board Hot Cat. I'm sure they're great. Maybe a titch different, but not all that important, at least not important enough to make one desirable and the other undesirable.

Lovely sounding amps.

Hey, a hand-wired Mesa might sound a little different vs one with a circuit board, but I might prefer the circuit board model for that 'Mesa Sound'. You just never know with this stuff! If it sounds good, it's good!

 

[psamm]

To the point where it makes me curious... we haven't seen this before in a CAD amp. There are known incidents in the past where a vendor got bad solder that took a few years but oxidized and looked weird and bubbly like that does. It would IMO be unprecedented for PRS CAD amp to have more than one or two joints like that in the same amp unless it was potentially related to something like a bad batch of solder.

I could be wrong of course, but we haven't seen a CAD amp with even a few solder joints like that.

That's a good insight about potentially bad solder. Hadn't considered that. I was going down the rabbit hole of just too low a temp being used - a brand new employee, etc. But, it passed QC - so maybe the joints have deteriorated over time. Thanks for the reply

 

[DreamTheaterRules]

That's a good insight about potentially bad solder. Hadn't considered that. I was going down the rabbit hole of just too low a temp being used - a brand new employee, etc. But, it passed QC - so maybe the joints have deteriorated over time. Thanks for the reply

I think Paul took a great deal of pride in the CAD amp line, and a great deal of care to make sure they were what he wanted. I’d run it by them and see what they say.

 

[DreamTheaterRules]

I will also note, because it makes absolutely no difference to anyone , this is why I much preferred turret boards, rather than these eyelet boards, when I was building a few amp circuits. Let’s say you stick a lead from a cap and a lead from a resister into this hole. Those two parts need to be soldered to each other, but they may only take up 20% of the space in the “eyelet.” If you look close at some of the ones above, you’ll see what I’m talking about. So then you’re trying to fill this big hole with nice smooth shiny solder. The hole is so big, that the solder just wants to flow on through it. So you go to the two leads and you try to flow a little more, and a little more around them until the hole is full. But if you try to hit the top one more time just to smooth the whole joint out so it looks nice, you run the risk of melting the built up solder and it flowing on through the hole and you start over. There are a few tricks, but it’s an unnecessary hassle. IMO.

Just saying, it’s not easy. And, if the two parts that need to be soldered together are completely soldered together with a good shiny solder joint, then the circuit integrity is good, and the rest of the hole isn’t really that important. IMO.

 

[László]

Inside an HXDA like mine that someone posted in the web. Looks like good workmanship to me, but I’m not an amp builder.

Looks better inside than a lot of original old Marshalls to these untrained eyes.

 

[DreamTheaterRules]

Inside an HXDA like mine that someone posted in the web. Looks like good workmanship to me, but I’m not an amp builder.

Looks better inside than a lot of original old Marshalls to these untrained eyes.

Very nice, clean build, and very nice solder joints on the ones I can see clearly!

 

[László]

I will also note, because it makes absolutely no difference to anyone , this is why I much preferred turret boards, rather than these eyelet boards, when I was building a few amp circuits.

Having met and talked with Doug Sewell a decade ago, I know that they spared no expense on these amps (though I was told that the best sounding parts were chosen regardless of whether they were expensive or inexpensive).

So, for durability, the eyelet boards are significantly thicker than what one would expect, and thicker than the boards used in the US non-CAD amps, which are thicker than the boards used by other amp makers.

It's my understanding that eyelet boards allow multiple thick leads to be used more easily than turret boards. Just going on what someone told me here. Could be wrong.

DTR certainly has experience in doing that, and I don't.

Here's an interesting video on how the amps are put together in final assembly; you can see that some of the wiring involves thick leads wrapped together for insertion into the same holes on the board. Whether these leads would fit into a turret I can't say.