Many acknowledge Fender's Princeton Reverb as a classic expression of blackface tone. The Sweet Spot is David Allen's take on that classic, and it delivers the goods: all the sparkling traits of the blackface era, at your fingertips and at a manageable volume.
I should also add that David Allen puts together top-flight kits. There is no need to sub in better components; the good stuff is already there! This is true of the chassis, transformers, small parts, cabinet—everything!
I have incorporated a few variations from the stock Sweet Spot circuit:
- 100k Bass pot vs. the stock 250k, to give more usable range
- 10k Midrange pot vs. the stock larger value that incorporates Allen's "RAW" feature
- 12AT7 reverb driver tube vs. the stock 12AX7, to more closely follow blackface topology and to take advantage of good tubes I had on hand
- 5Y3GT rectifier vs. the stock 5AR4, to change the DC operating point of the amp in order to reduce the output
- TO22 output transformer vs. the stock TO26, to give a "best match" for 6V6 output tubes
- Capacitor substitution in the tremolo oscillator, to allow a slower tremolo rate
Technical Rundown
- Circuit based on AA1164 Princeton Reverb amp
- Enhanced power supply and power amp
- TP25 160mA power transformer
- 5Y3 rectifier
- Vishay Atom and Nichicon electrolytic capacitors
- 2W metal oxide power resistors
- TO22 22W output transformer
- JJ 6V6GT power tubes
- New-issue Tung-Sol 12AX7 and JAN 12AT7 preamp tubes
- 1W carbon film signal resistors
- Mallory 150 coupling caps
- Cloth-insulated solid core hookup wire
- Finger-jointed, solid pine cabinet
- Floating birch ply baffle
- Eminence Copperhead 10" speaker (not pictured yet)
