Adcom GFA-5800 2 ch amplifier for sale in NJ

devani

I have the Adcom GFA-5800 Amp for sale.

I prefer local buyer and give perference to local buyers first. I also have the box for it. No manuals. Can be used with SDA by negative terminals grounded together...

8/10 condition.....located in 07885 NJ for pick up and hooked up to Monitor 10 A for demo. Too much of an amp for me....thanks...

$550

more info on the amp

Adcom GFA-5800 (Nelson Pass Design)
The GFA-5800 is unlike most amplifiers as it uses only MOSFET's in the signal path. NO bipolar transistors anywhere.
It also simplifies the signal path by using only three gain stages.
Built-in Bi-wire capability
250 + 250 watts RMS into 8-ohms from 20-20,000-Hz @ 0.18% THD
400 + 400 watts RMS into 4-ohms from 20-20,000-Hz @ 0.18% THD
Freq. Response: 10-20,000Hz [+0/-.25 dB]
Power Bandwidth: 3-130,000Hz (-3dB)
Dynamic Headroom @ 4-ohms: 2.1dB
IM Distortion: (CCIF 4kHz-20kHz) 100dB
Damping Factor from 20-20,000Hz: > 1100 (incredible!)
Gain: Unbalanced (29dB), Balanced (26dB)
Dimensions: 17" W x 8" H x 13.5" D
Weight 62 lbs

John in MA

I have one of these I've been trying to sort out for years. Any idea what the mode of operation for the fans is actually supposed to be? Most owners I've talked to have similar malfunctions to mine.

devani

john,
No I don't. but it sure looks simple enough to figure out if I had Pspice on my computer.....previous work place had it and would have run a simulation with LM317....

audiobilly

If this in the realm of what you are talking about. If the unit does not come with fans. I am not familiar
with the 5800, yet.

What about AC powered fans after the main Power switch? Lots of places to come out of the amp, some nice grommets, little mounting hardware, you are good to go. Get the correct size and CFM. High cfm fans can be noisy, some experimenting may be necessary.

I have two GFA-5500 that I have done this on, works great!

heiney9

John in MA wrote: »

I have one of these I've been trying to sort out for years. Any idea what the mode of operation for the fans is actually supposed to be? Most owners I've talked to have similar malfunctions to mine.

NM................this is a FS thread don't want to muck it up. John in MA I'll PM you.

H9

devani

$520.......bump~

bigaudiofanatic

WOOOOOW That would rock a set of LSi25's

dpowell

This amp is a powerhouse! Good luck with the sale.

devani

another bump with new price $500.....
anyone want this shipped??

devani

I can bring the amp to the Polkfest if anyone is interested....

also I can ship the amp if shipping is paid...

devani

new price bump! $480

kevhed72

Man, that is a great price. If this was for sale before I bought my Parasound, I would have bought it in a minute....:)

steelervic

i have had and compared the 5800 with the 5500, 555, 555II, 5802. i still have the 5800 and have sold the rest.

john, the fans come on at different temperatures, one when it starts getting warm and the other when it gets warmer. i measured them, but can't recall the temps. i also measured the temp of the 5500 and 5802, the 5800 ran cooler than both because of the fans.

the 5800 is a great amp, at that price your giving it away. if i could, i would have bought it when you first listed it. i highly advice you if at all finacially possible to keep it before selling at that price.

vic

devani

thanks vic and sal, I can bring the amp to the Polkfest if anyone is interested....

original box is included in the price...$480 for excellent condition Adcom amp

Lietuvis91

Kim wrote: »

If you look at the schematic there are two different values for the thermal switches that turn on the fans. The left side uses a 60 C switch, and the right side uses a 40 C.
Why two different values, I don't know...

could it be because the second fan only comes on if the first one cannot handle the duty of keeping the temps to a reasonable level? If you're not pushing the amp hard enough there is no reason for the second fan to come on and therefore it doesn't?! Just a thought...

I'm thinking of that becuase the fans in your car have 2 settings, hi and low, the fan comes on at a low setting at 180F and switches to high at 215F. It's a similar concept.

steelervic

thats correct

steelervic

and because of the fans, it stays cooler than the 5500 or the 5802.

heiney9

The reason the fans are used is because the heat sinks are enclosed. The 5802 has the heatsinks in open air.

The amps are similar with the 5802 getting the edge in sound and design. This is a great deal for a very nice amp.

steelervic

i compared the 5802 and 5800 side by side, same everything, i couldn't hear a difference. it seems like using the fans may be a better design, as the 5800 stays cooler than the 5802.

heiney9

steelervic wrote: »

i compared the 5802 and 5800 side by side, same everything, i couldn't hear a difference. it seems like using the fans may be a better design, as the 5800 stays cooler than the 5802.

Some designs are designed to run hotter so I don't buy that. Sure overheating is never a good thing, but a high bias A/B amp should get warm to very warm and a single ended Class A will get hot enough to make morning eggs.

If the parts and design are good enough then running warm to hot isn't bad, it's necessary. In this case since the heatsinks are internal Adcom felt fans were needed for proper cooling.

The 5802 doesn't need fans for cooling.

H9

devani

possible sale bump!

devani

still open to all buyers....

Earthy

It's a heck of a deal too.

infinity man

interested in buying adcom amp.

devani wrote: »

still open to all buyers....

infinity man

I live in New Jersey interesed in adcom,will also pick up

bigaudiofanatic

Trades?

infinity man

bigaudiofanatic wrote: »

Trades?

are u selling the adcom if so I'm willing to pick up.

infinity man

infinity man wrote: »

are u selling the adcom if so I'm willing to pick up.

I am trying to find out if the person selling the adcom 5800 is for real willing to buy & can pick up.

cstmar01

infinity man wrote: »

I am trying to find out if the person selling the adcom 5800 is for real willing to buy & can pick up.

I think we get the idea you are interested. However it would probably be better to send him a PM or email as it doesn't look like he's responding to your posts.

devani

infinity man wrote: »

I am trying to find out if the person selling the adcom 5800 is for real willing to buy & can pick up.

I am real and have made several transactions here.....sent you a PM....

devani

I have received your PM and I want to chew on this for a few days. I was surprised to see your offer lower than the my asking price but not by much....

Thanks...