jimmymcfarrell
pfm Member
For sale. Adcom GFA-555ii power amp. This is listed on eBay for £450. Not expecting to get that much for it but something in region of £400 would be nice. This being the case if anyone on here is interested I’m open to offers. £375 maybe.
The amp is in good working order but not perfect cosmetically. Has a few dents & dings. It’s been powering one half of the bass section of my Isobariks which seems a bit overkill for a system I hardly use.
The amp has been configured (internally) for uk mains (unlike most which you see listed as needing an external step down transformer) and it’s fitted with a uk mains plug. It still uses the original 2 core power cable so the grounding is provided from the source upstream via the RCA input. I always meant to fit a 3 core power cable with the earth connected to a point on the metal chassis but have never got round to it (once I got it wired up & in place I couldn’t face removing it to do so, due to the size & weight of the thing). I’ve had no issues with hum or ground loops in the current configuration but from an electrical safety pov a 3 core power cable would be a good idea. If this is a deal breaker for someone I’ll fit a 3core cable prior to sale.
Please see pics for confirmation of cosmetic condition.
It’s a heavy beast so postage won’t be cheap however I know it’s possible as it was delivered to me. I’ve still got the packaging (NOT an original Adcom box) it came in so will be well wrapped etc if needed to be sent. I’m in Plymouth so collection welcome and delivery maybe possible if you live anywhere south west of Bristol as I travel all over the West Country for work.
Specifications (copied from from Ken Rockwell on t’internet).
Inputs
100k Ω.
Two gold-plated, Teflon-insulted brass RCA jacks.
They are close enough together to make connection a breeze.
Gain
27 dB.
Input Sensitivity
1.75V for 200 W into 8 Ω.
130 mV for 1 W into 8 Ω.
Rated Power Output
200 watts per channel into 8 Ω from 20 - 20,000 Hz at less than 0.04% THD, both channels driven.
325 watts per channel into 4 Ω from 20 - 20,000 Hz at less than 0.04% THD, both channels driven (requires fan option to do this for any length of time).
600 watts into 8 Ω from 20 - 20,000 Hz at less than 0.04% THD, bridged mono (requires fan option to do this for any length of time).
850 watts into 4 Ω from 20 - 20,000 Hz at less than 0.09% THD, bridged mono (requires fan option to do this for any length of time).
Dynamic Headroom
2.5 dB at 4 Ω.
Power Bandwidth
1.7 - 100,000 Hz at - 3 dB.
Frequency Response
10 - 20,000 Hz +0, -0.25 dB at 1 W RMS into 8 Ω.
Damping Factor
Not less than 800 from 20 - 20,000 Hz into 8 Ω.
Noise
Not less than -110dB down from 200 watts into 8 Ω, A-weighted.
Power Input
120 VAC 50-60 Hz.
72 VA idle.
1,500 VA maximum.
675 VA at 200 W into 8 Ω.
I measure 37.5 watts at idle, cold.
60 watts at idle, warm (0.73A).
92 Watts (1.09A) when delivering 1 watt per channel into 8 Ω.
845 watts when delivering 265 watts per channel into 8 Ω.
It draws zero power when turned off because it has a real power switch. It's not like modern equipment that never really turns off and consumes power and remains a fire hazard any time its plugged in. The GFA-555 II is completely disconnected when switched off.
Size
Chassis: 6-3/4 x 17 x 12-3/16 inches (172 x 432 x 310 mm) HWD.
Overall: 7-1/4 x 17 x 12-3/16 inches (185 x 432 x 310 mm) HWD.
Weight
35 pounds (16 kg).
39 pounds (18 kg), packed.
Quality
Made in USA.
Replaced by
Replaced by the GFA-5500 in 1995.
The amp is in good working order but not perfect cosmetically. Has a few dents & dings. It’s been powering one half of the bass section of my Isobariks which seems a bit overkill for a system I hardly use.
The amp has been configured (internally) for uk mains (unlike most which you see listed as needing an external step down transformer) and it’s fitted with a uk mains plug. It still uses the original 2 core power cable so the grounding is provided from the source upstream via the RCA input. I always meant to fit a 3 core power cable with the earth connected to a point on the metal chassis but have never got round to it (once I got it wired up & in place I couldn’t face removing it to do so, due to the size & weight of the thing). I’ve had no issues with hum or ground loops in the current configuration but from an electrical safety pov a 3 core power cable would be a good idea. If this is a deal breaker for someone I’ll fit a 3core cable prior to sale.
Please see pics for confirmation of cosmetic condition.
It’s a heavy beast so postage won’t be cheap however I know it’s possible as it was delivered to me. I’ve still got the packaging (NOT an original Adcom box) it came in so will be well wrapped etc if needed to be sent. I’m in Plymouth so collection welcome and delivery maybe possible if you live anywhere south west of Bristol as I travel all over the West Country for work.
Specifications (copied from from Ken Rockwell on t’internet).
Inputs
100k Ω.
Two gold-plated, Teflon-insulted brass RCA jacks.
They are close enough together to make connection a breeze.
Gain
27 dB.
Input Sensitivity
1.75V for 200 W into 8 Ω.
130 mV for 1 W into 8 Ω.
Rated Power Output
200 watts per channel into 8 Ω from 20 - 20,000 Hz at less than 0.04% THD, both channels driven.
325 watts per channel into 4 Ω from 20 - 20,000 Hz at less than 0.04% THD, both channels driven (requires fan option to do this for any length of time).
600 watts into 8 Ω from 20 - 20,000 Hz at less than 0.04% THD, bridged mono (requires fan option to do this for any length of time).
850 watts into 4 Ω from 20 - 20,000 Hz at less than 0.09% THD, bridged mono (requires fan option to do this for any length of time).
Dynamic Headroom
2.5 dB at 4 Ω.
Power Bandwidth
1.7 - 100,000 Hz at - 3 dB.
Frequency Response
10 - 20,000 Hz +0, -0.25 dB at 1 W RMS into 8 Ω.
Damping Factor
Not less than 800 from 20 - 20,000 Hz into 8 Ω.
Noise
Not less than -110dB down from 200 watts into 8 Ω, A-weighted.
Power Input
120 VAC 50-60 Hz.
72 VA idle.
1,500 VA maximum.
675 VA at 200 W into 8 Ω.
I measure 37.5 watts at idle, cold.
60 watts at idle, warm (0.73A).
92 Watts (1.09A) when delivering 1 watt per channel into 8 Ω.
845 watts when delivering 265 watts per channel into 8 Ω.
It draws zero power when turned off because it has a real power switch. It's not like modern equipment that never really turns off and consumes power and remains a fire hazard any time its plugged in. The GFA-555 II is completely disconnected when switched off.
Size
Chassis: 6-3/4 x 17 x 12-3/16 inches (172 x 432 x 310 mm) HWD.
Overall: 7-1/4 x 17 x 12-3/16 inches (185 x 432 x 310 mm) HWD.
Weight
35 pounds (16 kg).
39 pounds (18 kg), packed.
Quality
Made in USA.
Replaced by
Replaced by the GFA-5500 in 1995.