DG Custom 30 amp disappointments

[Prina]

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).

It's interesting looking at the board components they used on the 25th Anni amp: F&T (and Nichicon blue) filter caps and metal film resistors for the power supply, and for the signal: Sozo coupling & bypass caps, with carbon film resistors and carbon comp for the V1 Ra and all the V3 LTPPI resistors. Very similar to what's in the pic of the HXDA which isn't surprising since they're both Plexi circuits.

The only ones that might be NOS would be the carbon comp resistors.

 

[László]

It's interesting looking at the board components they used on the 25th Anni amp: F&T (and Nichicon blue) filter caps and metal film resistors for the power supply, and for the signal: Sozo coupling & bypass caps, with carbon film resistors and carbon comp for the V1 Ra and all the V3 LTPPI resistors. Very similar to what's in the pic of the HXDA which isn't surprising since they're both Plexi circuits.

Not that I fully understand the significance of each part, I only know what my light reading in various articles has told me over the years; however, it does seem that Doug was very specific about the parts he wanted in these amps.

The last electronic thing I built was a Dynaco stereo FM tuner in 1974. I had to solder parts onto a circuit board, but it didn't require that I know what the parts individually did. It was more like building a plastic model as a kid where the instruction sheet tells you what to do.

Nonetheless it sure LOOKS impressive!!

 

[Prina]

Not that I fully understand the significance of each part, I only know what my light reading in various articles has told me over the years; however, it does seem that Doug was very specific about the parts he wanted in these amps.

The last electronic thing I built was a Dynaco stereo FM tuner in 1974. I had to solder parts onto a circuit board, but it didn't require that I know what the parts individually did. It was more like building a plastic model as a kid where the instruction sheet tells you what to do.

Similar experience here. My older brother and I built a couple of Heathkit kits including a TA-16 guitar combo amp. Definitely a paint by numbers sort of thing except that you have to get it all right for the kit to work.

I know WAY more about amps than I did a few months ago. I was really pleased with the Archon 25 combo, especially the clean channel that can get into Marshall JTM 45 territory when you push it, as well as the gain channel for the times when high gain is needed. It's not a CAD amp but it's great USA thick PCB construction and very well done with significant hand wiring and chassis mounted tubes & pots. With clean and gain covered I realized that the next PRS I needed was a HXDA to really cover the EOB middle. Unfortunately they're not too common and a bit more costly than the $650 that the Archon was. Ultimately what I wanted was a high quality Plexi (late '60s 50W model 1987, non-MV) and decided to build a clone myself using a kit from Scotland, nearly in the same town as @Alnus Rubra, using most of the same parts that the HXDA uses. More on that later.

And I agree that the CAD amps use high end parts, and likely more importantly, which high end parts to use and where to use them to get the best sound. For example using the old school carbon composition resistors in the locations I noted previously where they can influence tone the most. Carbon comps are noisy, have wider variation in resistance between resistors and don't have great thermal stability. But that's what the those classic Plexis used and I don't doubt that Sewell tried both carbon comps and carbon film resistors and went with what sounded the best.
And I'm also impressed with the HXDA's lovely ground bus.

 

[DreamTheaterRules]

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.

Completely true. And if you have a couple parts and a heavy wire, it’s great. Many times it’s just two small (cap/resistor) leads and the hole is much larger than the parts you’re soldering. No question, they are super heavy duty and built to be easy to service. I just prefer to build on a turret board. And the look. But I’ve built on heavy eyelet boards like this before.

 

[Prina]

I just prefer to build on a turret board. And the look. But I’ve built on heavy eyelet boards like this before.

Cool. What have you built?

 

[DreamTheaterRules]

Cool. What have you built?

let me get me get on from a PC later this evening. I have at least a few pics.

 

[László]

For example using the old school carbon composition resistors in the locations I noted previously where they can influence tone the most. Carbon comps are noisy, have wider variation in resistance between resistors and don't have great thermal stability. But that's what the those classic Plexis used and I don't doubt that Sewell tried both carbon comps and carbon film resistors and went with what sounded the best.
And I'm also impressed with the HXDA's lovely ground bus.

Fortunately, the HXDA is dead silent, unless you're playing through it, or your pickups or pedals are noisy (mine aren't).

It's pretty amazing to have a Plexi style amp that's this quiet! The DG30 is quiet, too.

Come to think of it, my Mesas are also quiet. Maybe it helps that the rest of my rig doesn't have hums and buzzes anywhere? I'm asking, not saying it's one way or t'other.

 

[DreamTheaterRules]

Cool. What have you built?

I’ll need to wait til I get to work Monday. My new personal laptop at home doesn’t have those old pics on it. I have a personal laptop at work that has a few.

 

[Alnus Rubra]

Ultimately what I wanted was a high quality Plexi (late '60s 50W model 1987, non-MV) and decided to build a clone myself using a kit from Scotland, nearly in the same town as @Alnus Rubra, using most of the same parts that the HXDA uses. More on that later.

Whereabouts as a matter of interest?

Asking for a friend

 

[Prina]

Whereabouts as a matter of interest?

Kirriemuir.

Maybe by Scot standards 14 miles from Dundee is not 'nearly in the same town' but in California double that distance can be in the same city.

 

[Alnus Rubra]

Kirriemuir.

Maybe by Scot standards 14 miles from Dundee is not 'nearly in the same town' but in California double that distance can be in the same city.

Close enough for friends.

The home town of Bon Scott, although he was born in Forfar.



You probably know all this though.

 

[Prina]

You probably know all this though.

No. Thanks for the info.

Bon: live fast & die young. Too bad that he died so early as it would have been awesome to hear 'Long Way to the Top' live in the half dozen times we saw them.

 

[psamm]

I heard back from PRS Support yesterday, and I'm SOL and on my own it appears.

No acknowledgement of the poor quality solder joints throughout the amp.

"The DG 30 was “lightly” filtered from the beginning, as David Grissom set the values exactly how he used the amp- edge of breakup. If you max out the gain, some light ghosting might occur. But, if the filter caps are getting tired, they may be causing out of spec ghosting. Caps have a lifespan, and these may need to be looked at. Please let me know if you would like to send this in for service, we have a bench fee of $100 per hour plus parts. We are currently at a 2–4-month backlog on repairs."

I take responsibility for not addressing this during the warranty period. I failed to open and examine the chassis myself. Dumb, and a lesson learned.

Sadly, the main takeaway for me will be an ongoing distrust of PRS amps. The DG30 will be both my first and last experiment with the brand.

I'll reflow every solder joint in the amp myself, and possibly replace the main filter caps. I'll report back on any outcomes.

 

[ruger9]

This sounds like a case of using the amp in a way other than intended? For example, Fender blackface amps controls go to 10, but the bass and treble controls weren't designed to actually be used at 10; many amps with Master Volumes weren't designed for the MV to be used at 10. When you're talking about tubes and analog components, the useful range of these things is not always from 0-10, unlike most digital/modeling platforms.

If you dial in the amp for edge of breakup, does it perform properly? If you're running the gain at 10, maybe you need an amp that is deigned to provide more gain than the DG30? I love the "clean" side of my Bad Cat Hot Cat cranked up, to maybe like 1:30. Beyond that, the gain becomes to woofy and loose to be useful. This is not a design flaw: it's how much useful gain the amp has on that channel.... you want more, you swtich to the lead channel where there's ALOT more gain.

If you think something is actually wrong with the circuit, I'd try to find a local tech to take it to, rather than send it back to PRS at $100/hour (plus whatever shipping charges would be...ouch.). But I'm starting to wonder if there is anything wrong it, or if you're just using it in a way it wasn't optimized for?

 

[psamm]

Agreed and I always understood that the DG30 was an edge of breakup amp. I carefully noted DG's recommended amp settings on a couple of his clinic demos.

The ghost notes occur within the range of MV and Volume settings and I've experimented across the width of the tone controls. That started my path of disappointment.

The other issue is that the amp just doesn't do anything for me. Notes don't bloom, the high end is sterile, and there doesn't seem to be much character at all. It's lifeless and completely uninspiring. This is in direct comparison to every other tube amp I own.

All of this led me to finally inspect the chassis only to find the low quality solder joints throughout. I'm seeing that even the grounding points' soldering is half-done and cold looking.

I'm an amateur but experienced amp builder and will do the clean up and possible filter cap replacement myself and will certainly not be paying PRS fees for a 2-4 month backlog and shipping back and forth to fix their low-quality build. I'm pretty baffled that they didn't admit to the obvious soldering flaws - my small hope was that they'd take some accountability, but ultimately blame myself for not taking action sooner.

To be fair, I never remotely considered (as I kept trying to like the amp) that the problems could be related to a bad build. I assumed too much, clearly.

 

[Wyzard]

This sounds like a case of using the amp in a way other than intended? For example, Fender blackface amps controls go to 10, but the bass and treble controls weren't designed to actually be used at 10; many amps with Master Volumes weren't designed for the MV to be used at 10. When you're talking about tubes and analog components, the useful range of these things is not always from 0-10, unlike most digital/modeling platforms.

Early and mid-period Boogies have a bass control that you generally set close to zero for higher-gain settings: ignoring this advice produces some pretty cr*p results

 

[László]

Agreed and I always understood that the DG30 was an edge of breakup amp. I carefully noted DG's recommended amp settings on a couple of his clinic demos.

It's disappointing that you have to do all that work yourself, though you seem to be up to the task.

It's weird, I have one of the first 20 made, and in 11 1/2 years have only had to change a single preamp tube that went bad. The amp still sounds superb.

I'm an edge-of-breakup player, like you. If anyone asked me to recommend an amp that'd be perfect for my style of play, I'd suggest playing through one to see if it's for them.

Problems with the amp are simply off my radar because of the good luck I've had during the period I've owned it. I'm genuinely surprised that yours is problematic.

 

[ruger9]

The other issue is that the amp just doesn't do anything for me. Notes don't bloom, the high end is sterile, and there doesn't seem to be much character at all. It's lifeless and completely uninspiring. This is in direct comparison to every other tube amp I own.

OK so, stuff like this could also be guitar-caused: meaning the pickups. I have found certain guitar/pickups "mate" better with certain amps. I'm sure DG developed the tone of the DG30 with a DGT. Those guitars are somewhat of an enigma in PAF-land; not only is the DGT bridge the best sounding PAF I've ever played, it sounds like a Les Paul and a telecaster had a baby LOL. I'm not saying the DGT pickups are so unique that they are making all the difference, but I could see them making some of the difference, regarding items like "sterile top end".

I definitely have guitars that sound great through some of my amps, and just OK through others.