Adcom GFA 555 II vs Yamaha M4 Amps

Nabnassett

Nabnassett

Well-Known Member
I'm currently running a Yamaha M4 from a recently restored Yamaha C4. From there everything goes into a pair of ADS 1230s.

The M4 hasn't been touched and likely needs to be. The plan was to recap and adjust it then enjoy it. Sure.

I've found an Adcom GFA 555 II that's advertised as rebuilt but that means different things to different people. Half a can of Deoxit or totally gone over. I haven't seen or heard it but it's got me thinking.

Say that both were rebuilt, clean, and running well, would one have any benefit over the other? I know defining sound is akin to describing the color green.

Wondering if anyone has experience with either, or better yet both. It's a longshot but worth a try.

Thanks in advance!

Dave
 
Register to hide this ad
What speakers are you running? The Adcom has quite a bit more power. 200 watts vs 120 watts.
Some speakers will benefit from more power, some will have all they need with the Yamaha.
 
Thanks for the reply.

Running a pair of ADS 1230s, 6 ohm. Suggested power 60-200W

I don't think that the M4 is having issues pushing the speakers, they sound pretty good, at least to me.

I guess I was just wondering if the Adcom was an upgrade in any other than power.
 
I was able to see the amplifier early this afternoon. The seller had advertised it as Refurbished but said that basically all that was done was the fuses replaced (3 were blown as a previous owner had installed the wrong ones), power switch cleaned, Bob's you uncle...

It sounded great but the fuse situation has me concerned. If someone put the wrong ones in there must have been something wrong with the previous fuses. Additionally, I don't believe the unit has protection relays and with power issues I kinda backed off.

Again, sounded great but the fuses and Refurbishing concern me. Probably doesn't make a difference but I get a good feeling powering up the M4, counting to 5 and hear the relays click in.

Thanks all!!!!!

Dave
 
So long as all of the output devices are original, or are at least all of the same type & spec, I wouldn't worry too much about blown fuses. My own 555 MKI blew the fuses (and the bench breaker) when I tried to drive it into clipping at 2Ω. Replaced the fuses, and didn't try that again.
 
arts said:
So long as all of the output devices are original, or are at least all of the same type & spec, I wouldn't worry too much about blown fuses. My own 555 MKI blew the fuses (and the bench breaker) when I tried to drive it into clipping at 2Ω. Replaced the fuses, and didn't try that again.
Click to expand...

I appreciate the reply.

Not sure I understand the meaning of Output Devices and wonder if you'd expand on that.

The 555 II would be driving a pair of old but rebuilt ADS 1230s rated at 6 ohm. I wouldn't think there'd be an issue as my current M-4 runs them smoothly but hard to say, at least for me.
 
Nabnassett said:
I appreciate the reply.

Not sure I understand the meaning of Output Devices and wonder if you'd expand on that.

The 555 II would be driving a pair of old but rebuilt ADS 1230s rated at 6 ohm. I wouldn't think there'd be an issue as my current M-4 runs them smoothly but hard to say, at least for me.
Click to expand...

He means the output transistors. Had those required replacing, it would imply a larger problem had occurred.

I wouldn't put too much worry into the wrong fuses being installed at one time. You see that all the time, people use what they have on hand rather than seeking out the correct parts.

I really don't think the Adcom would have any issues with your speakers. Mine drive twp pairs of speakers in parallel. I even broke the "rules" and drove two pair of speakers with the amps bridged with no trouble at all.
 
Nabnassett said:
Thinking of going to have another look at it tomorrow afternoon.

Will report back.
Click to expand...

If you don't have a fair amount of electronic knowledge or experience, it will be really hard to spot issues. And bigger amps like this can be difficult and expensive to "put right" after some bumbler has had a go at it, as there are fewer and fewer of the old guys left who actually know and understand these machines. Although I prefer the MKI, the MKII is also fine amplifier, so long as it's unmolested.
 
Maybe take the cover off. If a real hack was in there bad/sloppy work might be obvious even to the untrained eye. Some, though admittedly not all, unskilled work can stick out like a sore thumb.
 
I'm planning on bringing a Philips screwdriver and at least pull the cover. I've already asked the seller.

As mentioned, there's likely not a lot i can really tell about past work unless its some bat-**** crazy stuff. Solder splatter, sketchy etches, dead mice, etc are pretty easy to spot. It's what you don't see...

As an impressionable and inexperienced teen I bought an old Blackface Fender Bandmaster amplifier. I took it home, fired it up and was having a blast until I started smelling something. A buddy of mine who'd taken apart a few more radios than I had pulled the fuse and found it wrapped in aluminum foil.

To this day the sniff test is still an invaluable tool. If something smells like burning toast or popcorn it's time to walk.
 
Checked out the previously mentioned 555II this afternoon. Amazing how good condition the cabinet was.

Seller played it again into a pair of Polk speakers that I wasn't familiar with. Cranked it pretty loud and I was a bit worried about the speakers but the amp didn't break a sweat.

Pulled the cover and rust everyplace. Transformer, chassis, screw heads. Didn't look like anyone had been in there mucking around but with all the corrosion it didn't look like it'd be long before they were.

I'm guessing that the piece spent a fair amount of time in a garage or damp basement at some point. I passed on it and feel bad but glad I saw it.

Onward.

Dave.
 
I don't know how as a seller you wouldn't look inside the unit.

I never have sold a unit without looking inside.
 
Just selling anything can be a huge PITA.

20 years ago I sold a 16' sailboat. Put an as in the old weekly Want Advertiser. Guy called asked if he could try it out. Sure!

He showed up with his girlfriend and a 6 pack in a cooler. Standing on the dock he tells me he'd never sailed before. He walked when I told him I'd need 500.00 before I could let him take it out. Pretty sure he not only didn't have the asking price let alone the 500. She was kinda cute though.
 
BilboBaggins said:
The seller is a flipper. My definition of one.The kind who buys stuff as cheap as he can and sells quickly. They don't want to hang on to anything.
Click to expand...

I am the same way with the exception of cheap. I want pretty close to market value, and will get close to it or better. I must be a different kind of flipper......

And I do not want to look foolish selling. I want folks to be happy with their purchase, and not waste time one way or the other.

One big caveat....no phone calls, and no texts. That eliminates many folks, but it has always also eliminated problems.

I called somebody for the first time in forever last week because of how we exchanged emails. You could tell he was sincere, and had difficulty getting here from his destination which was 9 miles away. Give me your address. He did along with his phone #. Called him and delivered. Gave me an extra $10 for gas without me asking........And I don't mind driving back north up through University Parkway so I can see how the 10% live........
 
Last edited:
I mean the type that buy and sell as fast as they can because as long as they are holding onto the stuff, their money isn't making any money for them.

When I was doing this, (I still am, but not aggressively), I tested, cleaned, and fixed the gear as quickly as I could, but even that takes time. Only on very rare occasions do I sell it without getting to know the gear well. Once for a pair of Technics SB-7000. I had just gotten them the night before, and while I was in the getting to know them stage, my son and a couple of his friends dropped by, and one of them insisted on buying the technics. Another time, I had an Optonica turntable I had just picked up, and someone came to check out a pair of speakers. He ended up leaving with the speakers and the Optonica. I regret both of those sales, because I never did get to know them.
 
You must log in or register to reply here.
Back
Top Bottom