HX/DA INFO (and my NAD 50 W Head(s)) Share your HXDA knowledge with the world!

No question that my HXDA will outlive me by many years.



Just gonna say we pretty much think alike...But you have more! In addition, you get bonus points for springing for the Tube Cube.

I feel insecure now.

I mean, what if I live long enough to use all the tubes I'm saving for the future, need more, and can't find good NOS stuff? Will I be forced to dumpster dive as a very old dude, looking for "previously owned" tubes?

"But these test the same as new, Les!"

"Oh sure. But who knows what sockets its pins have been in?"
I can only say I regret my misspent youth. I could have bought these things for a couple of bucks a pop all day long. I keep hoping I’ll stumble into a warehouse full of classic tubes, cases and cases of pristine goodness.

Oh, and a date with Ksenia Buzina, while I’m dreaming.
 
I can only say I regret my misspent youth. I could have bought these things for a couple of bucks a pop all day long.

Likewise. Of course, in a few years, you'll be able to say you could've bought these things for $100 a pop all day long...

My misspent youth was actually a lot of fun. But yeah, misspent. But fun. ;)
 
Likewise. Of course, in a few years, you'll be able to say you could've bought these things for $100 a pop all day long...

My misspent youth was actually a lot of fun. But yeah, misspent. But fun. ;)
I’ve got a set of the Siemens tubes coming. If they sound as good as I expect, I’ll slowly build a little stash of those too! Plan to visit my estate sale. :D

Edit... I got the Tube Cube when I was gigging with the Road King II. There are a slew of tubes in that dude, so I kept a full set in the trailer, safe and secure in the Tube Cube. I think you could park a car on that thing. Still has a set in there which, thankfully, I never needed. Better to be prepared than end up playing the night on some solid state keyboard amp!
 
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I’ve got a set of the Siemens tubes coming. If they sound as good as I expect, I’ll slowly build a little stash of those too! Plan to visit my estate sale. :D

Edit... I got the Tube Cube when I was gigging with the Road King II. There are a slew of tubes in that dude, so I kept a full set in the trailer, safe and secure in the Tube Cube. I think you could park a car on that thing. Still has a set in there which, thankfully, I never needed. Better to be prepared than end up playing the night on some solid state keyboard amp!

I often wonder what I would do at a gig if my amp failed.
 
I’ve got a set of the Siemens tubes coming. If they sound as good as I expect, I’ll slowly build a little stash of those too! Plan to visit my estate sale. :D

Edit... I got the Tube Cube when I was gigging with the Road King II. There are a slew of tubes in that dude, so I kept a full set in the trailer, safe and secure in the Tube Cube. I think you could park a car on that thing. Still has a set in there which, thankfully, I never needed. Better to be prepared than end up playing the night on some solid state keyboard amp!

I actually bought some of the Mesa branded Siemens tubes when Mesa said they'd found them in their warehouse. Definitely genuine. Sounded perfect.

So I bought a several more sets of them. I'm old enough that it's a lifetime supply. ;)

I have some of the boxed original logo Siemens tubes, too.
 
I often wonder what I would do at a gig if my amp failed.
I carry my two 513s in a Mono dual guitar case, and keep a FlyRig5 in the pocket, just in case I need a quick replacement to my main rig. I've never needed it, but it's tiny and sounds decent enough to get by for a show, or if my fellow guitarist had his amp go down. Prior to getting it (and maybe as justification for the purchase) we did get bad power one night, and his amp released the magic smoke. I use a Furman PL-Pro DMC power conditioner, which shut down the power before any damage happened to my rig. Since then, I don't gig any rig of my own without some power protection.
 
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I actually bought some of the Mesa branded Siemens tubes when Mesa said they'd found them in their warehouse. Definitely genuine. Sounded perfect.

So I bought a several more sets of them. I'm old enough that it's a lifetime supply. ;)

I have some of the boxed original logo Siemens tubes, too.
Awesome! They're a little expensive, but they're brand new and that does count for something. I get what you're saying about a lifetime supply. I remember Lou Holtz saying "I'm so old, I don't even buy green bananas anymore." I feel like that some mornings. But I'm going to make sure I don't go to my grave playing some crappy Chinese tube. :eek:

And absolutely no one will ever want to hear me attempt accordion! I've heard some killer players, from my days recording down at Q-Zone in Corpus Christi, but I can only make the sound of a painful, wheezing screech attack. Then again, sometimes my guitar playing sounds like that, too!
 
And absolutely no one will ever want to hear me attempt accordion! I've heard some killer players, from my days recording down at Q-Zone in Corpus Christi, but I can only make the sound of a painful, wheezing screech attack.

I got big smiles and high fives when I pulled out an accordion for some 'Cajun-influenced tracks on a session for some car ads I did in Europe a while back. The clients were delighted!
 
By the way... HX/DA Discovery Wednesday:

I was going to list how each type of pedal performed with the amp, as a help to anyone who might follow this using a 25th Anniversary, HX/DA, or even a DG30. But I have discovered exactly what Les mentioned a few posts back: "I use mine with other pedals, and you bet, it's a great match for pedals (if they're good sounding pedals in the first place)." This has proved true in every instance, and I am just going to say that the amp handles pedals very well. So, in the GI/GO principle, if the pedal you're using sounds good, what you will hear coming out will sound good. If not, get a new pedal. :)

And, all joking aside, it is ridiculous the dearth of information available on this amplifier. A tube chart. That's it. No other printed (electronic or otherwise) information have I found. I did find another video of Bryan Ewald demoing the HX/DA:

HX/DA 30 Combo

Demoing the "Bass (DA) Channel" HX/DA 30 Combo


And "Lead (HX) Channel" HX/DA 30 Combo


Paul Demoing his own Custom Recording 100, the predecessor to the HX/DA


and Tim Pierce demoing his 50 and 100 HX/DA heads


I am hopeful that PRS Staff will add some documentation or insight to this thread. More to come....
 
We should form a Tube Brotherhood. :)
This is true! I love all kinds of guitar gear, and modelers are awesome these days. I've got an Axe Fx III, and love it. But you're just never going to replace the experience of a playing through good tube amp. It is its own thing.

May the soft glow of NOS glass forever light your musical path, Brothers of the Tube. Or, Brothers of the Valve, if you happen to be in other parts of the globe.
 
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The videos pretty thoroughly cover the territory; there was a terrific demo early on in Paul's studio that sounded so good that after watching it, I immediately ordered one.

I think the amp's operation is pretty straightforward; there was a sheet (not really an owner's manual) on the PRS website re: the 25th Anniversary amp, upon which the HXDA is based. It might still be available for download. Most of the info applies, except that the wattage switch was changed to a master volume control, and there weren't the switches for input, tone stack, and cathode follower.

Because Tim Pierce's demo of the amp shows off how well the amps respond to the guitar's volume control, and how good it sounds at higher volumes, I think it's a great source of info on the amp's possibilities.

Really, it's just great to experiment with an amp and find whatever for you is its sweet spot. I have some Mesa amps, and they have excellent owner's manuals, but sometimes I think that it's just as useful to turn the controls and see what happens!
 
The videos pretty thoroughly cover the territory; there was a terrific demo early on in Paul's studio that sounded so good that after watching it, I immediately ordered one.

I think the amp's operation is pretty straightforward; there was a sheet (not really an owner's manual) on the PRS website re: the 25th Anniversary amp, upon which the HXDA is based. It might still be available for download. Most of the info applies, except that the wattage switch was changed to a master volume control, and there weren't the switches for input, tone stack, and cathode follower.

Because Tim Pierce's demo of the amp shows off how well the amps respond to the guitar's volume control, and how good it sounds at higher volumes, I think it's a great source of info on the amp's possibilities.

Really, it's just great to experiment with an amp and find whatever for you is its sweet spot. I have some Mesa amps, and they have excellent owner's manuals, but sometimes I think that it's great just to turn the controls and see what happens!
True!

@Tahlee added a copy of the sheet from the 25th Anniversary model near the beginning of this thread. I added a copy to my records for the HX/DA. I'd love to get a schematic as well, but haven't found anything more in depth than the tube chart. The schematics exist... but whether it can be viewed by mere mortals is another matter!

A few more demos:

HX/DA 50 and 2x12 Cabinet:

Sweetwater Demo w/ Mike Clark:

Paul and Mike Ault/Nicky Moroch with the HX/DA:
Points that Paul makes here, interpreted by a person that can't be sued for saying Duane Allman, Jimi Hendrix, Allman Brothers, or Marshall:

HX/DA Info

This amplifier was cloned from Duane Allman’s Marshall amplifier, which was used on the “Live at the Fillmore” recording. This amplifier, on inspection by PRS and Doug Sewell, turned out to be more a Marshall bass amp circuit than the expected normal Plexi. The HX/DA, with all switches in the DA setting, is this amplifier.

Jimi Hendrix was using Marshall Super Lead 100 (1959 Plexi model) amps in the period following this, which are a modification of the circuit encapsulated in the DA settings. The HX settings make this conversion when all activated. You can use any combination to explore sound possibilities.

Switch 1- Moving this to the HX setting takes some of the bass out of the first stage, which begins to take it towards the brighter sounds of the Super Lead amp.

Switch 2- Moving this to the HX setting adds some gain, which Paul points out is in the cathode follower.

Switch 3- Moving this to the HX setting changes the feedback resistor, another modification that Marshall made in creating the Super Lead Plexi used by Hendrix.

And Part 2:

A great 30 watt demo showing how volume and picking on the guitar end can make tons of variation in drive on the amp, from Wilcutt Guitars:

and His Grissomness demoing at NAMM 2013:
 
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Found an internal HX/DA 50 photo, which saved me from taking mine out of the cabinet to satisfy my curiosity!

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And one more from Reverb, which has two less fuses in the top left. As I don't know what the fuses do (schematic anyone? :rolleyes:), I'm not sure why one has two and one four... they both appear to be two-power-tube versions. Oh, Doug Sewell, where forth art thou?

P6FzzEl.jpg
 
The Mike Ault video is what sold me on the amp. In the photo without the fuses, maybe they simply took a pic of the amp while it was being built or serviced?
 
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