Sold to Maxim in NYC!
And the amps just keep on rolling! This is the nicest GFA-545 II I’ve ever restored. Cosmetically, It’s pretty close to perfect! The face is nearly flawless. There’s just one scratch that I’ve touched-up on the top cover, towards the back, and a two barely noticeable scuffs on the sides. Click on the photos to see it in hi-res. Overall, it looks just about brand new.
But it’s better than brand new! This is a complete tear-down and restoration using every trick I’ve learned about Adcom amplifiers.
- Power supply capacitors upgraded from 10,000uF to 15,000uF Panasonic TS-HA 105C for higher current reserves, longer life, lower DCR and more ripple current capacity.
- All electrolytic capacitors replaced with carefully selected audio-grade capacitors from Nichicon and Panasonic. Signal capacitors upgraded to WIMA MKS.
- Transistors in the critical input stage are matched for gain. This step is important to assure low DC offset at the output, and low distortion.
- Circuit boards cleaned and all solder joints re-flowed and inspected.
- New power switch and spark-supressor capacitor.
- New and higher-rated surge-protection MOV. I replace them even when they test OK. They’re known to develop latent failures due to exposure over time to moderate spikes.
- Sealed Bournes trim-pot installed for precise bias adjustment and better reliability.
- Heat sinks added to the transistors in the thermal protection circuit. (These are known to run hot and burn the board.)
- Emitter resistors changed from 5% tolerance sand-cast types to mil-spec DALE LVR 1%. These are more reliable, and frankly, prettier.
- 25A bridge rectifiers replace original 10A.
- Heavy-duty gold-plated binding posts.
- A high-quality snubber capacitor is installed across the AC power input to reduce RF interference and reduce noise.
- All wiring is obsessively neatened.
I measured 130WPC into 8 ohms, just before clipping.
As a listening test, I’ve been using this amp to power my mid-range drivers for about a week. It sounds so sweet!
Contact me here if you’re interested…