2016年3月9日 · So, do yourself a favor: Get the Electro Harmonix power tubes. They're a solid new manufacture tube with very, very few complaints. Get a bunch of the Sovtek LPS tubes for the V-12, V-13, V-14, V-15 positions as well as the phono positions. The Sovtek's won't break the bank but will give you a solid base to work from.

AEA custom restores the Fisher 500-C into a modern, extreme high-end amplifier. We source excellent condition core receivers and perform a complete restoration that entirely transforms the sound quality of the already legendary 500-C.

2011年7月22日 · It employs a specially developed RF amplifier tube combined with three tuned circuits for maximum selectivity, sensitivity and rejection of unwanted signals. Early versions of the 500-C (serial #’s 10000-20000) used the same FM front end as the 500-B which was a Golden Cascode design.

2016年10月13日 · For the 7591A output tubes, Brent Jessee has NOS Westinghouse for $140/matched pair. That is what I would choose if I was re-tubing a 500C. I would avoid the current-production Electro Harmonix Russian tubes, even though they are far cheaper.

2005年6月19日 · The 500-C's amplifier section has five front-end inputs: two phono inputs and a tape-head input (all three of these use the phono stage but with different equalization options selected), a monitor input, and an Aux input. The phono/tape-head stage uses one 12AX7 tube per channel for about 20dB of amplification.

2016年2月25日 · The 500C Owner’s Manual shows the tube layout. V16 and V17 are for phono and tape head, which won't come into play if you use the AUX input. Here’s what I found to sound the best as the result of my tube rolling last year:

2019年7月29日 · The 500C shows the 330K grid resistors and 0.047 uF couplers and I believe is one of the units where a change to 200-220K grid resistors and 0.068 uF (or 0.1 uF) couplers is recommended, particularly for new production tubes like the TS or JJ's.

Tube complement: seven 12AX7 (phono, tone control, phase inverter stages); four 7591 (output stage), 6HA5, 6HR6, two 6CW4, three 6AU6/EF94 (tuner stages). Output power 30Wpc at 0.7% harmonic distortion (14.8dBW) into 8 ohms from 8 ohm tap, 75Wpc "total music power." Frequency response: 25Hz–25kHz, ±1.5dB. IM distortion (60Hz/7kHz, 4/1) 0.7%.

2015年6月22日 · So it was with a high degree of skepticism and anticipation that I tried one of the heralded heavyweights of vintage hi-fi – the Fisher 500C receiver. These are tube-powered 35 watt per channel receivers from the 1960s.