Adcom GFP-750 or Belles 21A?

steveinaz

TOOLFORLIFEFAN wrote: »

Maybe it's just being proud of what one has acomplished in a short time, I know someday my Adcom setup will be a thing of the past. But rest assure if and when I go deeper in what you like to call the rabbit hole I won't be an ****..

Hope being on your soap box has got you feeling better about yourself..

Larry.

Place him on ignore and move on, you won't miss much.

reeltrouble1

Well that is an option steve.

I know we travel different audo paths. So your using Adcom now?

Missed that.

RT1

megasat16

What happened today, Big Ted?

Your Tubes got violated by Adcom?

FTGV

As a public service I will gladly remove all of those offensive sounding GFP750 boat anchors from your rigs.Alternatively you can ship them direct (at your expense ofcoarse.)

BIZILL

since ted says so, send me the adcom. surely you wouldn't want your friends to know you've got one. sorta like doing a larger gal. so long as your friends don't know.

reeltrouble1

Its OK Mega nobody likes their baby called ugly. Tool is just pointing out that as I got bigger so did my backside highway I concur. Still does not change anything, Belles trounces Adcom. H9 will forgive me.

RT1

FTGV

BIZILL wrote: »

sorta like doing a larger gal. so long as your friends don't know.

LOL the type you have to chew your arm off so as to not risk waking them as you leave?:)

F1nut

Someone is pushing buttons.

reeltrouble1

and its not Mr. Walker.

RT1

F1nut

That's for sure.

headrott

What gives RT1? You are usually opinionated (which I think is a good thing), but not to the point of being obnoxious. I am not trying to takes sides with the Adcom crowd or the Belles crowd at all. I am just saying, make your point and move on, and leave it up to the OP to makes his mind up. I usually enjoy reading your posts RT1 and many times agree 100%, but let's not overdo the provocations.

Greg

lakesailor

In fairness to the GFP 750 it is to Adcom what the M series is to BMW. It is NOT your everyday Adcom. Not suggesting that I think Adcom is a premium brand, but the GFP 750 is a good pre-amp by ANY standard, and a bargain if you factor in the price.

In this case I would likely go with the Belles...mostly becuase tube rolling in a pre-amp is so darned entertaining.

heiney9

Guys let it go, RT1 is just pushing buttons, trying to get under people's skin. For some of you he succeeded. It's what amuses him sometimes.

H9

reeltrouble1

once there was a Kingdom with a large Castle, of course inside the Castly lived a King. Now the castle was surrounded by a forest (seems there is always a forest around a castle) only this forest was different whoever was to go in never came out.

two men went in, they did not come out, 10 men went in they did not come out, 20 men went in they did not come out. then for a long time nobody ever went in to the forest only an occasional eagle or hawk might fly over it and time passed.

one day a new lad came to the Kingdom, it seemed to him the Kingdom was a rather dull place so he went and asked the King "Hey King, is there anything exciting to do around this place?" The King replied "yes" but I do not recommend iyou do it, it is dangerous". The young lad thought and said sounds just like what I am looking for.

So the lad and his dog headed off into the forest. It was soon quite dark as the trees did block out most of the light, over the years they had grown unimpeded their limbs pervaded the light and trail, making it hard to see or travel deeper on the path. But the lad and the dog pushed on and miles past.

Then they came upon a large pool of water and stopped to look down at it, suddenly a large hand shot up from the water high into the air covering the space then just as quickly it reached down and grabbed the lad's dog pulling it down disappearing beneath the water.

The lad did not panic though. He just thought to himself "This must be the place".

RT1

Ricardo

oh, ok.

Toolfan66

heiney9 wrote: »

Guys let it go, RT1 is just pushing buttons, trying to get under people's skin. For some of you he succeeded. It's what amuses him sometimes.

H9

He did succeed, and I got it after I posted so I have no hard feelings. it did hit me out of left feild...

heiney9

TOOLFORLIFEFAN wrote: »

He did succeed, and I got it after I posted so I have no hard feelings. it did hit me out of left feild...

I've been on here for awhile and even met and had a great time with Ted in person and it took me a while as well not to fall for it everytime .

The thing is we are all so passionate about this hobby, which is a really good thing, that it's easy to get a little lost in that passion and wanting to butt heads a bit.

It's all good and I was sincere in my prior post with my impressions. Because I am so enamoured with tubes, I'd choose the Belles for that reason. Just be prepared to spend some money tube rolling.

Last I checked with all my tube gear and my quest to roll and collect some of the best tubes around I've spent over $1200 just on tubes. This month alone I've spent almost $300 on tubes for the Norh I just bought for the office rig.

I have a tube pre and (3) tube integrated amps.

$1200 for old discarded little glass bottles with rare metals and chemicals inside made by many since dead craftsmen who took many of those secrets to their grave.

Don't let anyone convince you today's tubes are as good as the tubes of yore. I have yet to find a current production tube that can match the sound of old, expertly manufactured tubes of yesteryear.............believe me, you will know it when you hear it!!!

H9

cstmar01

reeltrouble1 wrote: »

once there was a Kingdom with a large Castle, of course inside the Castly lived a King. Now the castle was surrounded by a forest (seems there is always a forest around a castle) only this forest was different whoever was to go in never came out.

two men went in, they did not come out, 10 men went in they did not come out, 20 men went in they did not come out. then for a long time nobody ever went in to the forest only an occasional eagle or hawk might fly over it and time passed.

one day a new lad came to the Kingdom, it seemed to him the Kingdom was a rather dull place so he went and asked the King "Hey King, is there anything exciting to do around this place?" The King replied "yes" but I do not recommend iyou do it, it is dangerous". The young lad thought and said sounds just like what I am looking for.

So the lad and his dog headed off into the forest. It was soon quite dark as the trees did block out most of the light, over the years they had grown unimpeded their limbs pervaded the light and trail, making it hard to see or travel deeper on the path. But the lad and the dog pushed on and miles past.

Then they came upon a large pool of water and stopped to look down at it, suddenly a large hand shot up from the water high into the air covering the space then just as quickly it reached down and grabbed the lad's dog pulling it down disappearing beneath the water.

The lad did not panic though. He just thought to himself "This must be the place".

RT1

awww I thought the story was going to end with and then they came upon a clearing where all sat was the men of old who had died listening to the Belles and along side sat the 750 smoking from the last time God struck it down saying you are no Belles, get the hell out of here..

er something like that

The 750 is a great pre IMO, and I have yet to hear the Belles, however I think the tube rolling and from what I hear about it, would make it a great pre to try out as well. Tube rolling is a venture in itself so I would say go for it! The 750 is still pretty easy to come by if you decided the Belles wasn't for you and wanted to sell it and grab the 750 back.

megasat16

Ok Ted! For an instance, I was a little worried you blew a tube or a fuse or something.

Adcom is Adcom and Belles is Belles. No comparison there. But Ted, if you must know, there is big Wolcott P400 Ref pair on the gon. Thought you need bigger tubes not to blow.

george daniel

Hmmmm,, all Belles are not made equal.;)

cheif pontiac

Uhhm so which is better?

george daniel

cheif pontiac wrote: »

Uhhm so which is better?

Belles 20A

danz1906

cheif pontiac wrote: »

Uhhm so which is better?

I think its like comparing Apples to Oranges, both Pre-Amp are
good and on the same level, BUT different.

reeltrouble1

belles trumps adcom, actually it jumps up and down on it and pulverizes it, sure talk about what makes a pre amp or amp better or not, perhaps nobody knows and its a peanut gallery with juju beads. adcom is about power on the cheap, they came along in the late seventies and filled the market a bit after NAD. Certainly not the first two, but each quite succesful nonetheless.

so then who wants to actually describe circuits, resistor types, gain design, capacitors, tubes, power supplies you know audio stuff, anyone??

RT1

FTGV

reeltrouble1 wrote: »

so then who wants to actually describe circuits, resistor types, gain design, capacitors, tubes, power supplies you know audio stuff, anyone??

RT1

Deal me in.:)

Ricardo

reeltrouble1 wrote: »

so then who wants to actually describe circuits, resistor types, gain design, capacitors, tubes, power supplies you know audio stuff, anyone??

RT1

Audio stuff? That would be electronics stuff. You don't need to know squat on electronics to enjoy music.

RG1

heiney9

reeltrouble1 wrote: »

belles trumps adcom, actually it jumps up and down on it and pulverizes it, sure talk about what makes a pre amp or amp better or not, perhaps nobody knows and its a peanut gallery with juju beads. adcom is about power on the cheap, they came along in the late seventies and filled the market a bit after NAD. Certainly not the first two, but each quite succesful nonetheless.

so then who wants to actually describe circuits, resistor types, gain design, capacitors, tubes, power supplies you know audio stuff, anyone??

RT1

Sorry RT1, but you can't generalize Adcom like that. They had a few stellar pieces one of them being the Adcom 750 and the 5802 amp and their dac's. The rest of it is as you describe.

Straight from the horses mouth (Nelson Pass):

"It's a differential pair—the end. A single gain stage, balanced input, balanced output, no feedback....We took a pair of MOSFETs, and the inputs go to the gates of the MOSFETs. The MOSFET sources are tied together and biased with a current source, with the signal taken off the drains. [The circuit] can run unbalanced on either side, although the performance is best when it's run balanced."

If you think you know more about it than he does; please feel free to enlighten us. Is it the end all, be all pre-amp, nope. Could they have used better parts in a few key areas like coupling caps? yep. Will it compete against the likes of Belles, BAT, Parasound, etc.

Absolutely

Would I choose the Belles over the 750? Most likely because I am enamored with tubes. If it was a SS Belles, I'd most likely stay put.

H9

megasat16

I think it's a little hot in here.

RT1's tubes must be burning bright red again.

I don't care what's inside both Adcom or Belles personally even if I know what it means. There is a reason why they both are LO-Fi to Mid-Fi products.

But hearing is believing regardless if what's put inside Adcom and Belles. Let the OP listen with his own ears. He may hear a difference or may not hear any difference between tubes and sand at all.

Toolfan66

If Adcom and Belles are both Lo-Fi to Mid-Fi what do you concider Hi-Fi??

Just curious as I know both are Mid-Fi, well the two pieces being discussed anyway..Adcom does have Lo-Fi products just as Polk Audio does as well.

heiney9

More design observations for the OP's benefit, not necessarily for anyone else.

Other than glue logic and the transistors used to drive the relays, the 12 active devices—four gain blocks, each with three devices—are HEXFETs from International Rectifier. The output stage is intended to function as a pure voltage source, making the GFP-750 relatively immune to cable differences or low amplifier impedances. As we've come to expect from Adcom, the preamp sports a honkin' big toroidal transformer, with multiple secondary windings for each channel. A large heatsink on the left-hand side carries the power supply regulator chips.

Both signal and control circuitry is carried on one large double-sided printed circuit board, though these are physically separated. The parts quality is superb throughout, and care has been taken to keep signal paths as short as possible. The input switching relays, for example, are all adjacent to the rear-panel sockets. Did somebody mention the proverbial brick outhouse?

In passive mode, the signal sees only input switching and the attenuator.