ADCOM GFA-565 Monoblocks
dcmartinpc
Posts: 844
I have line on a Pair of Adcom GFA-565 Monoblocks Locally. I have scoured the net and people have nothing but great things to say about these amps that I can find.
Anyone here have any opinions on these amps. Should I jump on them if the deal is right? I would be driving LSi9's with them for now, but who knows what the future will bring!
How would they compare to a Rotel RB-1090 or even a Parasound HCA-3500?
Thanks!
Don
Anyone here have any opinions on these amps. Should I jump on them if the deal is right? I would be driving LSi9's with them for now, but who knows what the future will bring!
How would they compare to a Rotel RB-1090 or even a Parasound HCA-3500?
Thanks!
Don
Living Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9
Post edited by dcmartinpc on
Comments
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I am running them now. Bring a multi meter with you and check the DC offset. You do this by removing the speaker cable and reading the voltage at the terminals. Let us know the cost and if the capacitors have been changed.
BenPlease. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
He says the capacitors have been changed in one of them for sure. The other one, I do not know. I am assuming I should check the voltage across the terminals when the amp is on, correct?
Any signs of the infamous leaking caps I can look for? Or is the voltage the sign that it has already happened. If their is no voltage, and the caps are still good, is it a job someone who is fairly comfortable with a soldering iron could do?
Is their a way by looking at the boards to tell if the caps have leaked and were not properly cleaned?
The price is $450 for the pair!!! Not each, for the pair!
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
With the amps on. Where are you located?Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
I am in Michigan.
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
I work on those amps, but shipping would be expensive. Just do the test and get back to us.
BenPlease. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
If they test less than 15mv, should I just pick them up. They are just over a half hour drive away, and I would like to make only a single trip. What is your opinion?
Thanks!
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
15mv is very acceptable. It is when you start getting into over 1/4vdc that you need to worry. Also let the amp warm up. A little DC offset is normal at start up.Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
$450 is a steal!!!!!!
I have been looking into these for 2 ch or threshold but the cheapest I have saw these go for is $900 -
I've owned a pair of them, not too bad and brutal power. At the price, you should already have bought them and DC offset is not the biggest thing to worry about when buying a vintage amplifier. Pop the top, make sure they work for more than five minutes and move on. The fact that capacitors have been replaced should make you pay attention but not pass them up.CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
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I am going to be checking them out this weekend I think. I also am working on a deal for a 5800... I am hopefully soon to become a proud owner of the GFA-565's, a GFA-5800, and I have an Original GFA-555 on its way to me now also! Somebody went a little ADCOM crazy! :eek:
In my defense, I do have a couple parasounds on the way too
Mayeb I just went Amp crazy!
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
How about a shoot out ?SDA-2BTL with custom IC
Adcom 565 monoblocks--Monarchy Audio M-10 preamp
Theta Data Basic Transport--Stello DA100 Signature DAC--Camelot Dragon Pro2 MK III
Harman Kardon T-55c TT
DH Labs Q-10 Signature Speaker Cables With Furez silver plated copper bananas
Revelation Audio Labs Prophecy Cryo-Silver Reference AES/EBU
Revelation Audio Labs Prophecy Cryo-Silver i2s digital cable
4 Furutech FP-314Ag with FI-11cu Plugs/FI-11AG IECs--- Power Cords
DH LABS REVELATIONS ICs-amps
Revelation Audio Labs Paradise cryo-silver ICs-Source to pre -
I will be doing a shoot out once I get everything. I will only be keeping a selection of the following:
ADCOM GFA-565 Monoblocks (Pair)
ADCOM GFA-555 Original
ADCOM GFA-5800
Parasound HCA-3500 Upgraded by Big Sky Audio (This is a DEFINITE keep)
Parasound HCA-1500a
Parasound HCA-1200II
Parasound HCA-2205A (I already have this amp, and it is a definite keep) - Soon to be upgraded by Big Sky Audio
I am going to go check out the 565's tonight. Hopefully they are good to go! If so, I will probably get them upgraded by Big Sky Audio in the near future also. Just to be sure they are good to go long term.
Hopefully everything checks out on them!
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
Lets see some pics
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How about a shoot out ?dcmartinpc wrote: »I will be doing a shoot out once I get everything. I will only be keeping a selection of the following:
ADCOM GFA-565 Monoblocks (Pair)
ADCOM GFA-555 Original
ADCOM GFA-5800
Parasound HCA-3500 Upgraded by Big Sky Audio (This is a DEFINITE keep)
Parasound HCA-1500a
Parasound HCA-1200II
Parasound HCA-2205A (I already have this amp, and it is a definite keep) - Soon to be upgraded by Big Sky Audio
I am going to go check out the 565's tonight. Hopefully they are good to go! If so, I will probably get them upgraded by Big Sky Audio in the near future also. Just to be sure they are good to go long term.
Hopefully everything checks out on them!
Don
Sure that's a great idea
Take all different kinds of used amps from different sellers, all different ages and unknown usage habits and then do a shoot out to see which sounds better :eek:. A recipe for disaster and it won't really tell you which one is better as a brand/model but which one is better in this singular test.
Test them all against factory specs, bring them back to life according to factory specs and then have a listening test; that's a lot more reliable, worthwhile and intelligent.
Congrats on all your amp purchases
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | Roon Nucleus 1 w/LPS - Tubes add soul! -
I definitely see where you are coming from... But I can only keep certain ones, and unfortunately I am only going to upgrade and refresh the ones I keep
So... I need to do a shootout for me personally, so I can decide which ones I like best in their default configurations, then send them off to Big Sky Audio. The HCA-3500 is going straight to Big Sky because I know I am going to keep that amp regardless. I already have the HCA-1200II, HCA-1500a, GFA-555, and the Parasound HCA-2205A in my possession. The 2205a is another keeper as I have had it for about a year, and it is the only 5 channel amp I have and I need it for my home theater Center, Surrounds, and Back surrounds. The 3500 will handle Front duty for the home theater and 2 channel. I will hopefully have the 565's tonight pending they test out correctly. Then to wait for the GFA-5800.
I can only work within my budget, unless someone else wants to pay to upgrade half of the amps
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
I have had my GFA-565 monos for almost 20 years and they have been serviced twice. They replaced two GFA-555's that were used for bi-amping my SDA-SRS's. The only Adcom amp that comes close to the 565's is the GFA-5802 and I get to play with both.
Leaky cap issues weren't the only problem with the 565. Both my amps had the transformers replaced under warranty within the first year. -
The 5802 is a stellar amp and I'd take it every day over any other Adcom amp including the 565's.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | Roon Nucleus 1 w/LPS - Tubes add soul! -
I never heard of a transformer failing in the 565's.Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
I had a loud mechanical hum develope in one of the amps and Adcom requested both amps be returned. The dealer actually loaded me a pair until they were repaired. I was told that both amps had the transformers replaced. I purchased these just after their introduction and maybe their was an early quality issue. Both amps also developed the leaky cap issue a few years ago and were repaired. I don't plan to part with these anytime soon. I just wish that they had the balanced inputs available on later 565's.
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Well.... I picked them up! One of them has a DC offset of about 20mV, which is not bad at all. The other one is showing about .5V or 500mV, which is obviously too high. But... drum roll please......... I picked the pair up for $350!!! I know I will need to get the one repaired, and quite frankly, I will probably send both of them out to Big Sky Audio to get upgraded caps and make sure that they both check out. But even at about $400 plus shipping for the upgrades, these are still an amazing deal! Basically, my ending investment will be about $800 or so. You can't buy a pair of these WITHOUT the upgrades for much less than $1000.
Anybody else agree on the deal I got, even with one that needs to be repaired? I hope I didn't make a mistake!
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
Nice grab but like all things audio these have dropped in value over the past 2 years. Anyone paying more than about $600 for a working pair (no high dc offset) is paying too much. At $1K for an original un-modded pair is simply getting soaked. About 5 years ago these were about $900-1000/pr for mint examples.
That said, you did well and once they are modded/refreshed you'll have a very nice pair of amps for a reasonable investment.
H9"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | Roon Nucleus 1 w/LPS - Tubes add soul! -
That was a great deal. Do you have a link to the place you are talking about having them upgraded.
BenPlease. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
Here is a link to the site, and directly to the GFA-565 upgrade page.
http://bigskyaudiomt.com/index.php?pr=ADCOM_GFA565
Why, do you want to upgrade/repair them for me Ben?
I did get them in the original boxes so shipping would be easy, wherever I would need to send them to. I could drive to Chicago, but I don't know any shops there that I would trust.
DonLiving Room: Adcom GFP-750 (Upgraded), Squeezebox Touch, Oppo BDP-83, Pioneer DV-79AVi, Parasound HCA-3500 (Upgraded), SDA SRS 2 P/B (Gimpod, Sonicaps, & Mills)
Theater: Denon 4311ci, Oppo BDP-93, Parasound HCA-2205+HCA-2200II, Polk LSi9, LSiC, LSiFX, LSi7, Custom 18" TC Sounds sub with 2 18" PR, Sharp XV-Z12000, Pioneer Kuro KRP-500M (isf Enabled)
Bedroom: HK AVR354, Pioneer DV-47a, Parasound HCA-1500a, Polk LSi9 -
I can do it. I just need to work it into my schedule.Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
Alot of the guys here help each other for no cost other than parts.
RT1



