Audio and Electrical Engineering
1965 Deluxe Reverb High Power Guitar Amp Build
"Hailed as the ultimate workhorse in guitar amplification, the Fender Deluxe Reverb is widely considered the most recorded amp in the history of music." — Happy Magazine
Much like my Tweed Deluxe build, I wanted one and I scratch built my own slightly modified one. Made in the USA pine cabinet, chassis, transformers, tubes, capacitors - all American. The speaker is a Made in the UK Celestion 50W Alnico Gold. This is a scratch built amp, with nothing more than the wiring and schematic of a 1965 Fender Deluxe Reverb. Parts came from Ted Weber, Tube Depot, StewMac and more. This is not a beginner build. Do not attempt without significant electronics experience — even if you have one of the DR kits available from MojoTone, StewMac and the like. A Deluxe Reverb is not a beginner build. Many amp techs can't fix one, let alone build one. Consider yourself warned!
Also, this gets crazy inside the chassis, but this is exactly how the originals were built by Fender back in the day. And that is exactly what I was going for. Besides, don't fix it if it is not broken and the most recorded amp in history is definitely not broken. Let's go!
Since I had a 15W Tweed Deluxe (it's definitely more power than that), I wanted the option of more headroom and power on this build. What I decided to change on my Deluxe Reverb build:
- Oversize power and output transformers so higher power is available without component failure
- This Deluxe Reverb clone can be run with 6V6, just like an original for ~ 18-22W output power
- Re-wire output tube sockets and bias circuit to accept all octal output tubes: 6K6, 6V6, 6L6, 5881, KT66, EL34, KT77, 6550 and KT88s — Note you cannot do this in a standard Fender or Fender clone amp without modification
- Allow use of multiple rectifier tubes safely, to change sag and output power characteristics. 5U4G gives less power and much more sag at volume; 5AR4/GZ34 will give ~ 15% more output power with less sag at max output
- Power Output with 5U4G Rectifier Tube
- Ouput is 18W clean at 8 ohms with 6V6s
- Ouput is 35W clean at 8 ohms with 6L6s
- Ouput is 24W clean at 16 ohms with 6L6s (note there are only 2/4/8 ohm taps, no 16, so less voltage is less power with 16 ohms on 8 ohm tap)
- With some of the big bottle tubes not originally available in a Fender amp, you can get ~40W
- Otherwise everything is exact clone of the original 1965 Fender Deluxe Reverb
Getting the chassis ready.
Chrome.
Starting to populate chassis mounted controls.
Real spring reverb tank, just like the original. Minus the bag.
Starting to wire the power supply.
Starting to populate the fiber board.
Dog house wired up.
Continuing work on fiber board and its hookup wires.
Power supply done, tested and working correctly.
Starting to figure out how to get the board in the amp. Meticulously double and triple check components and wiring. Note I switched the Chinese ceramic tube sockets to Micalex ultra high quality ones. I never want to replace these if I can help it. Note keeping track of all components and connections on a wiring diagram to know what's done and what isn't.
Starting to wire the tube socket side of the board to the amp chassis.
Board fully wired in and triple checked for errors.
Adding the knobs.
Checking everything one more time.
Fire up and testing time. Used a variac to bring up slowly. As above, power supply had already been tested. Just checking voltages on the A,B,C and D and bias sections of the amp.
Troubleshooting issue with vibrato circuit that ended up being new tube was actually failing. Replacing tube had it working with no other issues.
Testing max output power, noise and singal quality with a signal generator and oscilloscope. Note 400V+. Do not play around with tube electronics without knowing what you are doing or with someone who does. Note slightly modified bias circuit here from above.
Custom tube layout label. Speaker is a 12 inch, Made in the U.K. Celestion Alnico Gold rated at 16 ohms at 50 watts max.
Dropped in a set of NOS Sylvania and Phillips 5U4G, 6L6, 12AX7 and 12AT7. All american tube set, just like the Tweed Deluxe. Not too many more of these around. Biased and ran at output for a couple hours, checked bias and put it all together.
Amp is very quiet, sounds great, is quite loud and the reverb is as expected, fantastic.
