$300 amp versus $3000 amp ???

[Feanor]

Head to head my recently acquired Adcom GFA-555II against my Bel Canto eVo2i. Do all modern amps in good working order sound the same? Not a chance, friends.

I recently bought the Adcom on eBay with the intention of using it in bridged mode to power a DIY passive subwoofer I intend to built one of these days. This old unit does 200 wt/ch into 8 ohms; also, it does 850 watts into 4 ohms in bridged mode -- should be enough. The unit's last MSRP was $800; I paid $305 plus shipping, etc..

On the other hand I bought the Bel Canto new. It's last MSRP was $3200; it was $3000 when I bought it, but there were incentives going around and I actually paid only $2600.

Hello!! The Adcom is great all things considered. It has a smooth, slightly earthy character, and the bass is solid and very extended. I'm listening the Rene Jacob's version of Haydn's 'The Seasons' as I compose: really enjoyable. It reminds me a little of the NAD C270 I paid twice as much for a couple of years ago, except that the Adcom totally trounces the NAD for bass.

The Bel Canto is something quite different. Lighter, more neutral; the bass is as good as the Adcom's but not better. I suspect it would be easy for many people to prefer the Adcom's earthy warmth, but is the Adcom better? Undoubtedly not: where the Bel Canto cleans up is in the area of detail and transparency. Warmth might be tempting, but you can't argue with resolution. This is what you get for all that extra money.

I would like to go back to separates but I won't be settling for the Adcom, pleasant as it is.

[E-Stat]

Head to head my recently acquired Adcom GFA-555II against my Bel Canto eVo2i.

The Adcom is a good Nelson Pass designed amp built to a decided price point. One of those "great for the money" bargains. Enjoy it!

Do all modern amps in good working order sound the same? Not a chance, friends.

I find it amazing how many folks would disagree with that notion.

rw

[jocko_nc]

I'm currently digging an Adcom 545 II. Price was great, free. For the going rate of $200.00 or so, those old Adcoms are a great value.

For kicks, I am going to compare side-by-side with a monster Kenwood KA9100 I just picked up. That ought to be interesting.

jocko

[Feanor]

I'm currently digging an Adcom 545 II. Price was great, free. For the going rate of $200.00 or so, those old Adcoms are a great value.

For kicks, I am going to compare side-by-side with a monster Kenwood KA9100 I just picked up. That ought to be interesting.

jocko

It will be interesting to hear you conclusions.

I have no doubt at all that the 545 is a huge bargin at $200 -- perhaps one of the best you can get in amplification. On eBay you see all kinds of Kenwoods, Yamahas, Pioneers, and the like, that are apparently going for more money. Worth more? I very much doubt it!

[jocko_nc]

Yea, Feanor, that is exactly what I am wondering...

Is "desireability" based on performance or romantic attachment to the past. Let's compare the best of the late-70's with a more modern workhorse. Is there something to modern design? Are older components really old?

I wonder about all the "older-yet" equipment people seem to desire. Call it early to mid 70's. Marantz. Sansui. To me, that is nostalgia, a bit too old for performance. (???) Maybe that notion is way off base. (???) To me, its Japanese from the 1978-1981.

We are busy right now, I'll get around to it in time.

jocko

[JoeE SP9]

A lot of the current craze for older (vintage) Japanese receivers seems to be a result of comparing one of those old heavy workhorses against one of the new flimsy lightweight examples. Looked at in that way there is no comparison.
As far as any of them against an Adcom GFA-545 there is no comparison. The Adcom flat stomps all over them in clarity, detail and transparency. As far as bass goes they are simply in two different ballparks. The Adcom has bass that approaches true high end quality and character. The vintage receivers merely have nice bass.
If you want to improve an Adcom to the point of being a contender there are a few things you can do.
1. Replace the resistors with Vishay's
2. Replace the capacitors with Infinicaps or Musicaps or any other high quality caps.
3. Replace the rectifiers in the power section with high speed diodes.
4. Increase the power supply capacitance.
5. Replace the input connectors.
Optional
Change the AC cord to an IEC connector.
You have no idea how good the basic design of an Adcom is until you've heard one with upgraded parts.

[Feanor]

Yea, Feanor, that is exactly what I am wondering...

Is "desireability" based on performance or romantic attachment to the past. Let's compare the best of the late-70's with a more modern workhorse. Is there something to modern design? Are older components really old?

I wonder about all the "older-yet" equipment people seem to desire. Call it early to mid 70's. Marantz. Sansui. To me, that is nostalgia, a bit too old for performance. (???) Maybe that notion is way off base. (???) To me, its Japanese from the 1978-1981.

We are busy right now, I'll get around to it in time.

jocko

I've been looking at some vintage receiver offerings on eBay. Gosh, some are so georgious! The heyday was the late '70's. Marantz, Sansui, Pioneer, Kenwood, even Akai, especially the top-of-the line models. Sony and Technics (Panasonic) had some nice ones but not quite as splendid. Yamaha came along with some more sleek, "European"-style models.

Yes, I was alive and into hi-fi in those days. But even then I had moved beyond receivers. In fact I never owned a receiver, and by 1979 I had a Phase Linear 400, (spare me your comments on that one, please), and my Apt Holman preamp.

[kexodusc]

I've always liked Adcom - I had an old GFA-545 I sold to trade up to a used Parasound. I always regretted it, and later sold the Parasound for a GFA-535II. Then bought a second GFA-535II - I use those with another amp (Rotel, NAD, and AudioSource) in rotation in my home theater.
I really dig the 535's, they are much stronger than the 60 watts suggest - my NAD claims 100 watts, the Rotel and AudioSource 80, but the Adcoms deliver loud sounds with authority everybit as much as those without strain - I'm amazed the distortion lights still work.
I'm not a fan of the so called "warm" sound (which sounds completely unlike real, live music to me) which is probably why I like the Adcoms so much. On the used market they're a steal.

[jocko_nc]

I never had the jack for any of the "nice" stuff back then... Boy, I sure did oogle it though! I stared at lots and lots of equipment up there on the shelf. What I always wanted. Now, I can possibly find it cheap at Goodwill or a repair shop! (That Kenwood 9100 came from a repair shop, very good condition for $100.00. It would have been $200.00 on Goodwill and $300.00 on Ebay. I think I will shop those some more.) They are gorgeous.

I'll have to look into upgrading components on my Adcom, sounds like a good idea.

jocko

[jocko_nc]

There was a post on another forum regarding spending $30K on a HT. I'm a little wacky like that, but I'd stack some used Adcom 535 and 545's for power amps. A couple more for spares. $30K could go a loooong way and sound real sweet. Let's not mention speakers and subs. (o.k., I'll mention: Used. Kits. DIY's. PE / Dayton Reference. I want a pair of Seas Thor's. Heck, I have Vandy 2Ce's.) So many people spend so much and get so little. Of course, I am a little off the reservation.... ????.

jocko

[JoeE SP9]

I never had the jack for any of the "nice" stuff back then... Boy, I sure did oogle it though! I stared at lots and lots of equipment up there on the shelf. What I always wanted. Now, I can possibly find it cheap at Goodwill or a repair shop! (That Kenwood 9100 came from a repair shop, very good condition for $100.00. It would have been $200.00 on Goodwill and $300.00 on Ebay. I think I will shop those some more.) They are gorgeous.

I'll have to look into upgrading components on my Adcom, sounds like a good idea.

jocko

The easiest way to improve the sound of almost any power amp is to replace the input coupling capacitors (if there are any) with very high quality ones. Since only 2 are used (one for each channel) you can go a little crazy. If you later decide high quality caps are not worth it you're only out $20 or $30 bucks max.

[jocko_nc]

I was sort-of planning to do that with the Kenwood. 1978 is 1978. I would expect those to be in need. I recall Madisound sells them?

jocko

[2chAlex]

Hope it's alright to use this discussion to ask a ?. I too have been there for some time (long enough to remember Phase Linear and thinking someday). So maybe it's time to get into separates. I'm lucky enough to still have a brick and motar that deals used. They have Adcom (535, 545, and for abit more 555). From this discussion that might be the amps to go with. Also should pre-amp be same brand or just worthy of the amp. Adcom is available as well as Audiosource tuner 2 , B&K PT3 II

[jocko_nc]

Kex knows these things well... From what I read, the 545 got the good reviews. At a supposed 100 wpc, it will not shortchange a lot of speakers. I have been running for about three months now, believe me the amp has guts. I don't know that I would pay a big premium for the 555. From the sales literature, there were supposedly some improvements on the 545 II model. Kex says it was not such a big change. I have a 545 II and highly recommend it.

What is your use? Phono will change everything. HT will require a modern AV receiver. I use an AV receiver and have no complaints when running in "pure" two-channel mode. Sound for music fine.

jocko

[2chAlex]

Been thinking that seperates may be abit of overkill for myself. After reading AV forum for quite sometime then finally singing up this spring, that maybe I'm what's refered to as mid-fi. Granted it has usually been in the middle of a product line up. I had a A/V 5.1 reciever set up as two channel and it does ease some setup with connections and such. Had two recievers and that one sold the easiest. My current is older Sony ES pro logic which is run in two channel, usually in direct mode. The thing is like day one in operation and it seems to push a lot sooner than the 5.1 did for the same power rating. So long story short maybe I'm ok and just got bitten by the bug. Still think'n about intergrated though (remember those of Kenwood back in the day).although I would go newer. Still curious though about the pros/cons of intergrated versus seperates. My phono hasn't seen the light of day in sometime it keeps my laser disc company. So it's CD and xm by direct tv (bye bye music choice). Thanks for your time

[GMichael]

A lot of the current craze for older (vintage) Japanese receivers seems to be a result of comparing one of those old heavy workhorses against one of the new flimsy lightweight examples. Looked at in that way there is no comparison.
As far as any of them against an Adcom GFA-545 there is no comparison. The Adcom flat stomps all over them in clarity, detail and transparency. As far as bass goes they are simply in two different ballparks. The Adcom has bass that approaches true high end quality and character. The vintage receivers merely have nice bass.
If you want to improve an Adcom to the point of being a contender there are a few things you can do.
1. Replace the resistors with Vishay's
2. Replace the capacitors with Infinicaps or Musicaps or any other high quality caps.
3. Replace the rectifiers in the power section with high speed diodes.
4. Increase the power supply capacitance.
5. Replace the input connectors.
Optional
Change the AC cord to an IEC connector.
You have no idea how good the basic design of an Adcom is until you've heard one with upgraded parts.

Can you still call this amp an Adcom after all this? Seems like you are building an amp from scratch and just keeping the shell it came in.

[JoeE SP9]

Can you still call this amp an Adcom after all this? Seems like you are building an amp from scratch and just keeping the shell it came in.

You are probably right. What started out as small as changing the input coupling capacitors mushroomed over a period of years to what I have now. I haven't made any changes to the actual circuit designs just replaced most of the components with higher quality ones. My Dyna MK-III's are more in the line of new amps. The only thing they have in common with the originals is the transformers and the choice of output tubes. I designed new hard wired input driver boards (no PCB) using a 6CG7/6FQ7 as a driver and a 12AT7 as a phase splitter. I had experimented with a solid state power supply but it needed a soft start circuit to allow easy tube warm up so I went back to a GZ34 rectifier tube. The RCA tube manual (out of print) has been invaluable for any kind of tube design work. I have used high quality parts with my MK-III's also.

[hertz]

Hey JoeE,
For that much trouble one could assemble a AKSA dual mono power amp. Don't you think these would outperfom the modded ADCOM.

http://www.aksaonline.com/products_2_2.html

[GMichael]

Hey JoeE,
For that much trouble one could assemble a AKSA dual mono power amp. Don't you think these would outperfom the modded ADCOM.

http://www.aksaonline.com/products_2_2.html

I bet he had fun tinkering with it though.

[kexodusc]

Lots of people tweaked the Adcoms. For my part, the few cap tweaks I've heard didn't produce enough sound improvement for me to bother. I like the Adcoms and even Rotel for their bang for the buck. Once you start upgrading them, you get a bit more bang for a lot more buck. I think other used amps become more attractive at this stage - but that's just my line of thinking.

The 545II is supposedly a bit better than the 545 - for my part, I don't think my 535II's sound any better than a 535. The improvements were subtle - real binding posts instead of lock down spring clips - maybe nicer to work with, but no audible improvement generated, I'm sure. I think the 535 and 545 had a/b speaker selectors too, my 535II doesn't. I'm sure the electronics were upgraded a bit to accomodate the slightly modded rear plate, but I understand the bulk of the amps topology remained the same.

If there's a big premium on the II model, I'd get the original, it's definitely not worth spending much money on. If they're close in price, $20 or whatever you're comfortable with, it might be worth something to have the newer version.

I look it along the lines of a 91 or 92 Ford Taurus - are they really that different? The 92 might actually have more miles on it and be in worse shape?

[GMichael]

I remember seeing that the II of a couple of models were 4 ohm stable where the originals were not. Not sure of the model numbers though. If you have 8 ohm speakers it shouldn't make much difference.

[kexodusc]

I know the old 535-555's are 4 ohm stable - A lot of amps just didn't bother publishing the 4 ohm specs back then...not because they couldn't do it, just because the market they were targeted for didn't care.
You can download a spec sheet off Adcom's website on those models that shows them all being 4 ohm stable though. PSU's are the same, near as I can tell...same size, anyway.

[JoeE SP9]

Hey JoeE,
For that much trouble one could assemble a AKSA dual mono power amp. Don't you think these would outperfom the modded ADCOM.

http://www.aksaonline.com/products_2_2.html

Very true, it does seem like a lot of trouble. I'm not familiar with AKSA but I will check the link. I've had one of the GFA's more than 10 years and the other about 5. I just started with the input caps and couldn't stop! The changes took place over a period of years. Idle hands you know. I'm looking into some Transcendent Sound OTL monoblocks to drive my ESL's.

[JoeE SP9]

Lots of people tweaked the Adcoms. For my part, the few cap tweaks I've heard didn't produce enough sound improvement for me to bother. I like the Adcoms and even Rotel for their bang for the buck. Once you start upgrading them, you get a bit more bang for a lot more buck. I think other used amps become more attractive at this stage - but that's just my line of thinking.

The 545II is supposedly a bit better than the 545 - for my part, I don't think my 535II's sound any better than a 535. The improvements were subtle - real binding posts instead of lock down spring clips - maybe nicer to work with, but no audible improvement generated, I'm sure. I think the 535 and 545 had a/b speaker selectors too, my 535II doesn't. I'm sure the electronics were upgraded a bit to accomodate the slightly modded rear plate, but I understand the bulk of the amps topology remained the same.

If there's a big premium on the II model, I'd get the original, it's definitely not worth spending much money on. If they're close in price, $20 or whatever you're comfortable with, it might be worth something to have the newer version.

I look it along the lines of a 91 or 92 Ford Taurus - are they really that different? The 92 might actually have more miles on it and be in worse shape?

My two 545's don't have a/b selectors. I suppose I could add .....noooooooo!!!!

[JoeE SP9]

I bet he had fun tinkering with it though.

I may have become addicted to rosin fumes. I have had a lot of fun though. I have also perfected my soldering skills. I won't tell you guys what I did to my Haflers but here is a hint, fully regulated power supplies.