biscuithead
Me likes the eargasm retroplasm...
Can you trace the circuit and figure out what that fourth tube does?
Marantz Model 9 Prototype
- Thread starter bryans12v
- Start date
Can you trace the circuit and figure out what that fourth tube does?
biscuithead
Me likes the eargasm retroplasm...
You should open another thread titled " Possible Marantz 9 prototype?" maybe that will bring out the experts....
biscuithead
Me likes the eargasm retroplasm...
I am by no means an expert ... but this looks like the real deal... I hope you have found a rare bird! It should be in appreciative hands!
crooner
Tube Marantzed
So yes, you have the real deal. This is the Marantz Model 9 engineering prototype No. 6. Built by Sid Smith himself. It is known that it took forever for him to have this amplifier released as he was a perfectionist and was constantly making revisions to his prototypes, never satisfied.
crooner
Tube Marantzed
It is amazing that you found this. Most likely it was originally at Sid Smith's old home in Sea Cliff and now that it has been sold these prototypes are beginning to surface. This is the third known Marantz prototype. The others are the Model 7 prototype 3 that I posted above and the Model 5 prototype which I am posting pics now...
I think I need to get my hands on that now! Image that.
Sad part of this story is I'll probably never have a matching pair.
Holy smokes. This is soo unreal and incredible. I think the Marantz gods have been with me over the past year.
Awesome 
congrats its in good hands
congrats its in good hands
crooner
Tube Marantzed
It is the find of a lifetime my friend!!!!
I would not even sleep for days if I found that!!
I will be analyzing your pics very carefully for clues. The wiring for a prototype is excellent. I work with prototypes in my job and they never have any markings. Perhaps a serial number and that's it.
I would not even sleep for days if I found that!!
I will be analyzing your pics very carefully for clues. The wiring for a prototype is excellent. I work with prototypes in my job and they never have any markings. Perhaps a serial number and that's it.
Oh trust me, I'm having a hard time sleeping the past couple days. I think this piece may be more significant than I realize at the moment because I'm still jumping up and down just to have a model 9 let alone something 8000x more rare. I think there were about that many made?
Now I'm really torn thinking about making it active again. I'd really hate to have to replace parts. I'm hoping a matched set of the RCAs is all it needs. Will know more this weekend.
I'm about 90 mins from Sea Cliff. Pretty neat story. Keeping it local, kind of.
crooner
Tube Marantzed
They only made 1000 pairs of Model 9's including the rack mount versions. I am talking about regular non-prototype production. An engineering prototype number 6 could have been one of the last ones before the design was finalized. Take closer pictures of the back of the Bias pots for the date codes. The transformers both have codes of 352 which is the EIA code for Essex transformer company, an OEM for Marantz. The number right next to it is most likely a date code. "034" would mean the 34th week of 1960. The Model 9 was released in late 1960.
crooner
Tube Marantzed
Lots of interesting aspects to the design. The triode switch is at the front above the low filter. Production units moved this to the back close to the output tubes. A phase switch was added in its place on the front panel. The front panel has engraved lettering but the font is not the regular Marantz font. The power supply choke is not potted and it appears lifted from a Model 8/8B. It is located below the chassis. In production Model 9's it was placed right below the bias meter and in between the power and output transformers.
I wonder what the extra tube is doing... in all this is really fascinating. Will be looking at those pictures over and over in the next few days for more clues!
I wonder what the extra tube is doing... in all this is really fascinating. Will be looking at those pictures over and over in the next few days for more clues!
crooner
Tube Marantzed
What is even more amazing is that it appears untouched, never modified or modernized. The Model 7 prototype pictured on my earlier post had been extensively modded by Sid when he was working on his commercial modifications in the early to mid 1980s.
I would not change a thing on this amplifier, as it is historically significant. Luckily the Good all brand caps rarely go bad and there is no selenium rectifier, so with a VARIAC and an ammeter to monitor current draw it may be possible to power it up with no problems. The filter cans last forever also.
Another thing I just noticed is the fuse rating on the front panel. It is marked as 2.5A slow blow. The finalized version upped the value to 3A. But I always run my amplifiers with a smaller fuse as I find it draws less than 2A at normal levels.
I would not change a thing on this amplifier, as it is historically significant. Luckily the Good all brand caps rarely go bad and there is no selenium rectifier, so with a VARIAC and an ammeter to monitor current draw it may be possible to power it up with no problems. The filter cans last forever also.
Another thing I just noticed is the fuse rating on the front panel. It is marked as 2.5A slow blow. The finalized version upped the value to 3A. But I always run my amplifiers with a smaller fuse as I find it draws less than 2A at normal levels.
Pio1980
AK Member
I'd be sorely tempted to leave it a time capsule.
crooner
Tube Marantzed
If money was no object I would assemble a three channel system using three sets of KLH Nine electrostatic speakers and have the right and left channels driven by a pair of regular production Model 9's and the center channel would be driven by this prototype. Playing back discrete 3 channel stereo recordings from the golden era (RCA Living Stereo, Mercury Living Presence, etc). It would be out of this world!
crooner
Tube Marantzed
I know that for the Model 9, many different output transformers were tried. They finally settled for their own in-house wound version dubbed the TA-3.
This prototype appears to have been used to assess different transformers, perhaps late in the development phase of the Model 9. I know Saul was getting desperate to have the amplifier released and Sid was a known procrastinator. It took Dick Sequerra to help him finally get it released.
Interview with Saul Marantz:
Interview with Dick Sequerra:
This prototype appears to have been used to assess different transformers, perhaps late in the development phase of the Model 9. I know Saul was getting desperate to have the amplifier released and Sid was a known procrastinator. It took Dick Sequerra to help him finally get it released.
Interview with Saul Marantz:
Interview with Dick Sequerra:
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I think you are right on the money here as it looks like the trannies have been swapped quite a few times judging by the wear marks on the square pots that hold them. The front to rear rails are worn alot more than everything else on the unit. Oh my goodness. This is soooo unreal. I've taken out screws that Sid probably put in, for the covers, going to put them back in now.