HX/DA INFO (and my NAD 50 W Head(s)) Share your HXDA knowledge with the world!
RickP
Established 1960, Still Not Dead
I love the clean and open look. My music area is stacked so full of stuff that I am tripping over something no matter which way I step sometimes! I really need to re-work this space, and this is an inspiration.Thanks! The other side of the room is my workstation/composing area.
I was checking the readings on the power tubes... one is showing about 30.3, the other about 26.2 which means I'll have to get out a calculator and see what percentage off that is. Been a while. I've got one of those Eurotube meters to get the plate current and volts inline without popping the amp chassis out... a project for tomorrow if the storms aren't landing here this week. Waiting on the 10 pm advisory. Love the coast, except this part!
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Thanks! The space is a lot less "basement studio" looking with the lights dimmed. It's basically a good sounding space, and it's laid out pretty well for my work. Needs new flooring and a few details.
Re: biasing, I just use the bias points and adjustment screw on the rear of the amp with my multimeter, because my technical skills doing anything else are utterly nonexistent. In fact, I'm so electrical engineering-challenged that I have to keep the manual for the multimeter with the meter so I can remind myself how to actually use it.
Using a Eurotube meter would be a good idea if I actually knew how to interpret the additional information in the readouts!
By the way, their tube damper rings saved my Lone Star from hitting Reverb. Completely solved the rattle I was getting with the power tubes hanging right over the speakers on a 100 Watt amp. Good company to deal with.
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RickP
Established 1960, Still Not Dead
Speaking of “keeping the manual for the multimeter with the meter” I keep the instructions for the Eurotube Pro 1 wrapped around the unit with a rubber band! All the math for calculations, along with a tube chart for wattages, are on it. You just remove a tube, put the device into the tube socket, plug the tube into the back of the device plug (They “stack” in the tube socket) and fire the amp up. Because it’s inline, it reads the exact voltages and current the tube is seeing. Pretty cool, really, and you can play with it in there so you can see what effect that has on the tube. Plus, I’m not sticking my fingers into places with hundreds of volts of electricity waiting to bite them. The one I normally use has the meter one it, but I also have one that plugs into your own multimeter. They don’t get tons of use, but whenever I swap power tubes it’s good to know they’re set right!
I have a Carol-Ann Tucana 3, which is an incredible sounding 3 channel KT88 amp, and the designer rather thoughtfully added a bias setting circuit onboard that is awesome. Three lights, red/green/red top to bottom, and a bias pot. Warm the amp up, adjust to green, done. As it only uses one kind of tube, and a fairly stout one compared to 6L6 or EL34, it only needs to see one setting. You can set it hotter or colder, if you like, by the lights. Checked it with a meter, and it’s spot on. Great concept I’ve only seen on these amps!
This is the amp I added the Ox Box to be able to crank up, as those KT88s sound gorgeous when the master goes past 5. I’ll be putting that on the HX/DA too, because I’m sure I was nearing dangerous waters on that poor 50 watts of speakers yesterday!
EDIT: I found a video on the BiasMon funtion, narrated by Carol-Ann amp designer Alan Phillips:
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RickP
Established 1960, Still Not Dead
Sunday Amp Discovery:
1. Sounds amazing with the Hollowbody Spruce. Especially easy to coax cool feedback tones with it, though it doesn't feed back when just playing. Lovely!
2. Bias Update- My fave toy for biasing, the Eurotubes Pro 1, doesn't work well with this amp. In order to bias to the level suggested by the readings of about 405 to 411 VDC plate current, you'd have to go higher than the pot allows and put the mV reading at the rear test probe connections way high. I did some reading and found this is common, according to the Eurotubes site, which says "In older Marshall amps from the 1960's thru the 900 series amps the bias sweep or window only has about a 20 milliamp range, so in many of these amps the final bias resistor that is in series with the trim pot has been swapped out to move the bias window up or down to accommodate a colder or hotter set of tubes." I assume that, as this is a recreation of two old Marshall heads, that this is the situation, and is accounted for in the design. I biased the tubes to 30.2 mV on the probe points, and it sounds great. I'm going to leave it at that, unless I get some wise counsel otherwise.
3. Bias Update 2- As I mentioned in an earlier post, I was getting readings several mV apart (~15%) on the tubes in the amp. I had an older (2005) set of Winged C Marshall branded tubes, so I plugged them in. They read exactly the same on the bias probes. Looks like the others were just slightly mismatched, but good. I left the Marshall-version Winged Cs in there... it seemed appropriate for the history of the amp.
4. Pedals- I tried a few pedals to see how it dealt with those on the front end. At one time, PRS could add an effects loop to these, but I checked and it's no longer available. I like the way reverb or delay works in a loop better, but it's no big deal. As it turns out, everything sounded fine coming in the front door so far. An old TS9 Tube Screamer was a cool boost with the drive low and level up, and gave a tonal variation with tone knob settings too. I have a pedal that I love, that not many folks seem to know about. It's called the Secret Preamp, by Chase Tone. I have an Xotic EP Boost on the way, as lots of people love the Echoplex pre-boost it emulates. The Secret Preamp is a more elaborate Echoplex preamp recreation, and has all three versions of the Echoplex preamps. I'm tempted to just leave this one on all the time, it sounds so good, clean or distorted. I forgot how much I liked it! I will be curious to see how the EP Boost compares. Also began testing a few delay and verb pedals, and early indications are that this amp is a great pedal platform.
5. I love playing loud.
6. I want to hear this through a 4x12 cabinet.
7. 5 & 6 will likely never happen in my band, but I can hope. And it's fun at home anyway.
1. Sounds amazing with the Hollowbody Spruce. Especially easy to coax cool feedback tones with it, though it doesn't feed back when just playing. Lovely!
2. Bias Update- My fave toy for biasing, the Eurotubes Pro 1, doesn't work well with this amp. In order to bias to the level suggested by the readings of about 405 to 411 VDC plate current, you'd have to go higher than the pot allows and put the mV reading at the rear test probe connections way high. I did some reading and found this is common, according to the Eurotubes site, which says "In older Marshall amps from the 1960's thru the 900 series amps the bias sweep or window only has about a 20 milliamp range, so in many of these amps the final bias resistor that is in series with the trim pot has been swapped out to move the bias window up or down to accommodate a colder or hotter set of tubes." I assume that, as this is a recreation of two old Marshall heads, that this is the situation, and is accounted for in the design. I biased the tubes to 30.2 mV on the probe points, and it sounds great. I'm going to leave it at that, unless I get some wise counsel otherwise.
3. Bias Update 2- As I mentioned in an earlier post, I was getting readings several mV apart (~15%) on the tubes in the amp. I had an older (2005) set of Winged C Marshall branded tubes, so I plugged them in. They read exactly the same on the bias probes. Looks like the others were just slightly mismatched, but good. I left the Marshall-version Winged Cs in there... it seemed appropriate for the history of the amp.
4. Pedals- I tried a few pedals to see how it dealt with those on the front end. At one time, PRS could add an effects loop to these, but I checked and it's no longer available. I like the way reverb or delay works in a loop better, but it's no big deal. As it turns out, everything sounded fine coming in the front door so far. An old TS9 Tube Screamer was a cool boost with the drive low and level up, and gave a tonal variation with tone knob settings too. I have a pedal that I love, that not many folks seem to know about. It's called the Secret Preamp, by Chase Tone. I have an Xotic EP Boost on the way, as lots of people love the Echoplex pre-boost it emulates. The Secret Preamp is a more elaborate Echoplex preamp recreation, and has all three versions of the Echoplex preamps. I'm tempted to just leave this one on all the time, it sounds so good, clean or distorted. I forgot how much I liked it! I will be curious to see how the EP Boost compares. Also began testing a few delay and verb pedals, and early indications are that this amp is a great pedal platform.
5. I love playing loud.
6. I want to hear this through a 4x12 cabinet.
7. 5 & 6 will likely never happen in my band, but I can hope. And it's fun at home anyway.
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bodia
Authorities said.....best leave it.....unsolved
This what I recall setting mine to, when I had it.
I love my amp with the Fulltone Tube Tape Echo. I'm sure it'd sound great with the solid state version as well. Echoplex front end into a Plexi is a classic thing.
Also, 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).
I'm not an effects loop person; my favorite guitar tones have always been generated by players using effects in front of the amp, including delays. The signal gets cooked nicely, and becomes more organic, unless you're going high gain, where a loop seems to make more sense.
RickP
Established 1960, Still Not Dead
Thanks, Les. I am thankful for you, @bodia, @Tahlee, @MA Pete, and others sharing your insights and experiences with this amp. Pete’s Windy City post and your recordings that were on Soundcloud at the time were a big part of what put me on the trail of the HXDA to begin with!
Once you find your way around the controls, it’s surprising how fast you can dial in adjustments. It’s really cool how you can change the low and high end focus with just the two gain controls... never touching the EQ section. That has been really handy, making it very easy to return to your basic setup. I can’t imagine why these aren’t better known and more highly regarded.
bodia
Authorities said.....best leave it.....unsolved
Happy to help! Even happier to hear how much you like it.
Tahlee
Tollywood Rhode Island
I’m really happy that you bought the Xotic EP, Rick. I leave mine on all the time for a foundation of my dirty tone, and then I build upon that. I hope you love it.
You’re welcome. It’s really fun helping each other out.
You’re welcome. It’s really fun helping each other out.
RickP
Established 1960, Still Not Dead
The EP just came in this morning. I like it! Set to it's default it is clean and doesn't stomp all over the tone. I didn't expect it, but i can see using it and the Chase Tone preamp together, something I will likely try later tonight. I'm having a blast with it.
I tried the HXDA with the Silver Sky today, and it was another page in the tone book. Set right, this really got into some of those ZZ Top tones i was looking for, and (of course) it's an inspirational guitar to play. I don't live in that sound all the time, but I think I have the right vehicle to cruise the neighborhood when I want. So far, I haven't plugged in a guitar that I couldn't get to sound good with the amp. The greenbacks match with it well for getting that 60s era sound. I'm going to look for a V30 or similar 2 or 4 12 cabinet and see if it stays crunchy but cleans up a little when pushed hard. Those 25 watters are screaming for mercy at times. There are PRS 4x12 semi open back and 2x12 Big Mouth cabs for sale within driving distance... so tempted, but I have to replenish the money pool. Probably going to list a few amps on Reverb this week to speed that process (1967 Bandmaster and cab, and a Mesa 55 4x10). I haven't used either in ages and need to make room. Ahhhh, the circle never ends, does it?
Next up: The Universal Audio Ox Amp Top Box. My ears have been requesting this one for a few days.
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Beats me why more people didn't get one. Speaking only for myself, YMMV, it's the best sounding amp I've ever owned. That would include a lot of very highly regarded amps, by the way, many of them more costly than the HXDA. But everyone's needs are different, and these days high gain and two channels are more of a thing.
Mine's been my #1 amp since I got it in 2014 - I just love it. I thought about buying a backup just in case, but it's been bulletproof, so I picked up the DG30 instead of a second HXDA. And that's yet another great amp, but with a different voice altogether.
You have it exactly right when you say the HXDA is a breeze to dial in, and how useful the two gain controls are. One of my session player friends, who's also a fantastic producer in his own right, gave a pretty apt description:
"What I like about it is that you can hear the guitar, and yet you can also hear the distortion when you want dirt. But the distortion works with the guitar, it doesn't obliterate the guitar's tone."
I think that's kinda spot on. I like to say that the distortion the amp puts out is more like a halo of harmonics around the note, but you can still hear the guitar. And that's pretty darn consistent with the Plexis I played through in the late '60s. The fact that I can dial Duane's "Live at the Fillmore" tone right up in a few seconds, but then switch to something more my style with delays and modulation, without skipping a beat, is something ya can't put a price on!
RickP
Established 1960, Still Not Dead
Yes, great insights and descriptions all around. Funny you mentioned thinking of getting a second one. I thought the same thing today... grab one while they can still be found. I felt the same when Alan Phillips stopped making Carol-Ann amps. If I was rolling in cash, I probably would, but this amp appears to be very solidly made, as does the Tucana 3. Huge transformers, too! I'm betting it will be around as long as it's foundational amps.
Tahlee
Tollywood Rhode Island
I thought about getting another HXDA but I’d like to try the DG30. I have one arriving on Thursday. I will be reaching out to Les for his opinions. He made me start looking at nos tubes and my wallet doesn’t like them at all. But, I’m considering them since they last for a long time and I am a tone junkie.
Since my 25th doesn’t have those HX/DA toggle switches, I will need to get one at some point. “Need”. I crack myself up. I really appreciate that my wife doesn’t hassle me about my needs. 17 year old me would love and approve of 50 year old me.
Since my 25th doesn’t have those HX/DA toggle switches, I will need to get one at some point. “Need”. I crack myself up.
I really appreciate that my wife doesn’t hassle me about my needs. 17 year old me would love and approve of 50 year old me.
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RickP
Established 1960, Still Not Dead
“I will gladly pay you Tuesday, for a matched pairs of Siemens EL34s today!” - J. Wellington WimpyI thought about getting another HXDA but I’d like to try the DG30. I have one arriving on Thursday. I will be reaching out to Les for his opinions. He made me start looking at nos tubes and my wallet doesn’t like them at all. But, I’m considering them since they last for a long time and I am a tone junkie.
Since my 25th doesn’t have those HX/DA toggle switches, I will need to get one at some point. “Need”. I crack myself up.
I’m going to have to learn what a “real” Siemens EL34 looks like! I’d hate to get burned at that price point. I noticed several Mesa/Boogie tube sets out there that say they are Mesa branded, Siemens A-Grade tubes. I used to see them at Tubestore.com, but no dice. I’ll check Watford in the UK, they helped me stock up on Wnged C tubes.
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Tahlee
Tollywood Rhode Island
Oh my god, I can’t believe you said, “I’ll gladly pay you Tuesday for a hamburger today.” Words to live by.
Tahlee
Tollywood Rhode Island
How many pairs of Winged C is stocking up? I bought one extra pair, but I want more just to be safe. I really just want something to base my freakishness off. Hahaha. If you bought four pairs, I won’t feel silly buying a few more.
Tucson Thump
Mint Heavy Relic
Any combo that does Leslie West is stellar.
RickP
Established 1960, Still Not Dead
Oh, fear not... you're fine.
That's in addition to all the tubes in the 11 other tube amps in that room. If anyone has gone far overboard, it's me. About 20 of the NOS tubes on the shelf are Winged C/SED/Svetlana originals. I've got more rectifier tubes than three people would use in a lifetime. It's crazy. I know. Oh, and I did find a pair of Siemens branded EL34s in the box... on the way. Like I needed more.
Oh my god, I can’t believe you said, “I’ll gladly pay you Tuesday for a hamburger today.” Words to live by.
Now that is just next level connectedness. Life is good.
No question that my HXDA will outlive me by many years.
Oh, fear not... you're fine.
That's in addition to all the tubes in the 11 other tube amps in that room. If anyone has gone far overboard, it's me. About 20 of the NOS tubes on the shelf are Winged C/SED/Svetlana originals. I've got more rectifier tubes than three people would use in a lifetime. It's crazy. I know. Oh, and I did find a pair of Siemens branded EL34s in the box... on the way. Like I needed more.
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?"
