1997 Hot Rod Deville 410 Re-Tube

Mon Feb 04, 2019 10:23 pm

So I bought this 20 year old amp from the second owner who had played it a bit and put it in his closet. He had bought the amp from the original owner who had also played it a bit and put it in the closet. I think both of them had purchased something that was way more powerful than they were expecting. Because caps age whether or not they're used, I used my moderate soldering skills and recapped it shortly after buying it. Then I gigged with it for a year and you guessed it, put it in the closet! My plan was to eventually change the tubes because I wanted a warmer sound with better defined bass. Controlling the volume was a secondary goal. When "eventually" arrived and I pulled it out to work on, I discovered a busted power tube that was either broken moving it from a gig or from careless handling during a move. Either way, it sucked.

:shocked028: BEFORE YOU ATTEMPT ANY WORK ON AN AMP, MAKE SURE IT IS UNPLUGGED. IF YOU ARE DOING ANY WORK ANYWHERE NEAR THE CAPACITORS, DISCHARGE THEM ALL COMPLETELY AND DO NOT TOUCH THEM UNTIL THEY'RE DISCHARGED. EVEN AFTER UNPLUGGING AN AMP AND LETTING IT SIT FOR A CONSIDERABLE TIME, THERE IS SUFFICIENT AMPERAGE IN THE CAPS TO KILL YOU. Where I grew up, a person was said to be "dead" if they were knocked unconscious. If they were actually dead, they were said to be "dead finish". Charged capacitors in these amps have the ability to make you dead finish. BE CAREFUL PLEASE. :shocked003:

Tube Vendor: Eurotube
Tech: Self

Old Tubes:
V1 12AX7WA Fender Groove Tubes aka Sovtek PN 013341
V2 12AX7WA Fender Groove Tubes aka Sovtek PN 013341
V3 12AX7WA Fender Groove Tubes aka Sovtek PN 013341
Pwr Tubes Fender Groove Tubes 5881/6L6WGC aka Sovtek PN039214

New Tubes:
V1 ECC83S (Standard) JJ Tone
V2 ECC832 (12DW7) JJ Drive Channel
V3 ECC83S (balanced) JJ Phase Inverter
Power Tubes 6V6S JJ Matched Pair

This tube configuration is Eurotube’s “Blues Option” for the Deville $80. I substituted the 6V6S power tubes for the 6L6GC tubes in the option. Eurotube is actually in Oregon and not Europe and they deal exclusively in JJ tubes from Czech Republic hence their name.

Cleaned and lubricated sockets with Nu-Trol Electical Control Cleaner by spraying the old tubes contacts and inserting/removing from sockets several times. Then the new replacement tubes contacts were lightly sprayed and inserted as advised by vendor Eurotubes.

Allowed the amp to warm up for 45 minutes on Standby and played it w/ my new favorite thing G&L Fullerton Deluxe S500. I played rhythm and lead both before and after tube change with exactly the same settings and dB meter in exactly same position in an acoustically bright space. Using a multi-meter and the blue bias pot, I carefully biased it to 35.0 which I understand from Eurotube is a bit cold as far as these tubes go. Old tubes delivered 98dB compared to new tubes 103.8dB. Since the new tube configuration was designed to reduce volume somewhat, the difference I think can be attributed to the broken power tube in the “old” configuration.

New configuration delivers warm chimey tones with easy breakup on clean and is very sensitive to eq settings. Bass much more coherent (less muddy). Presence is very subtle and spring Reverb transparent and full. It’s a whole new amp! I may re-bias it a little hotter in the future just to see the difference in breakup.

After testing the amp, I connected a JHS Little Black Amp Box (Sweetwater $45) to the fx loop with astounding results. I cranked up the Deville to 4 (annoy the neighbors/peel paint off walls volume), dialed in the tone I wanted and with the single knob on the JHS brought the exact same tone down to conversational level. Great box if you have an fx loop to use it with. In spite of Sweetwater calling it an “attenuator”, the instructions from JHS says that it is not and must be used only with an fx loop.

I’ve got a killer amp! (Now if there were just a way to make it lighter.)

Wowie!

the Palm :banana:

Re: 1997 Hot Rod Deville 410 Re-Tube

Mon Mar 25, 2019 4:17 pm

After wanting to make my Hot Rod Deville lighter, I figured out how. I sold it and am waiting for delivery of my '65 Princeton Reverb 1x12" tweed. Went from a 50 pound amp with great tone and too much volume to a 34 pound amp with hopefully great tone and manageable volume.

Re: 1997 Hot Rod Deville 410 Re-Tube

Mon Mar 25, 2019 7:35 pm

i think you will like that choice!

Re: 1997 Hot Rod Deville 410 Re-Tube

Sun Feb 09, 2020 6:34 am

I bought mine new in 1998 and about ten years or so ago I made the same tube changes. I\ve also played with a 12AY7 in v1 but frankly I think the layout you have is perfect. It calms the clean volume immensely and makes the overdrive tones at least usable. Or occasionally I just dial in an edge of breakup tone on the drive channel and then use my guitar volume to dial back for clean tones, almost -- but not quite -- as nice as those in the clean channel. Ultimately I prefer to still use the clean channel with pedals as necessary but I'm not averse to using the drive channel for certain types of low OD tones, especially when boosted with a TS or another pedal. I still can't quite get a neutral EQ that works really well across the two channels, but honestly, I can get close enough. Overall, I think this is a brilliant and easy "mod" to make the amp very usable. I also made the reverb mod -- super easy -- and now have a far more usable reverb sweep as well, I've thought about the many other mods to balance the EQ etc but I think that's too much for my skills on a 20-yr-old PCB so I live with it.

I played for years with a simple volume pot in the effects loop and often left the clean volume between 7 and 9, for some pretty sweet edge-of-breakup tones at house-acceptable volumes, but of course that didn't bring in any power tube OD which was a shame.

So I built my own attenuator (about $50) which allows me to attenuate from -3.5db to -31.5db. This works phenomenally well all the way down, though I generally try to remain in the -21db range. There is no noticeable frequency loss and the amp is still pushing so much air that it is a real pleasure at what I'd call low stage volumes. I will say that this ain't no dumble or even bassman, Dimng the amp isn't a very pleasurable tone, but driving the clean and master volumes at around 9 to 10 gives some very acceptable noise!

I'f say that if this amp can be fully repaired for a little financial outlay, it's an exceptional big amp, and whatever people say, those four ten inch speakers mightily broken in are very well balanced. On the there hand, make the amp lighter b replacing the speakers with some neos - I have no experience with them but for sure the ones Fender are using in the ToneMaster amps sound pretty damned good (Admiteddly for digital music output). Contgrats mate!