NAD: 1964 Fender Tremolux

[hotcoffeenochill]

Howdy, y'all. Not necessarily brand new, I've had her for a week or so now. Picked up this "player" grade (replaced output transformer) 1964 Fender Tremolux. The power and choke look original and seem to be 63. Either way, a transition era Tremolux, blonde cosmetics but black panel and circuitry (AA763, allegedly). Came with a 2x12 Bandmaster cab. Speakers date the cab to 61. You can see it next to my Orange Retro 50 and 76-ish silverface Deluxe Reverb. I've also included gut shots. If any of you experts can actually confirm this is the AA763 circuit, I'd appreciate it. Also, I assume the new output tranny is also for 4 ohms, but is there any way for me to tell without a multimeter? I tried to do some research on the Heyboer codes but couldn't get much info other than it is, in fact, a Heyboer. Happy to take more pictures of specifics if you need them. Either way, for the price I paid and how good it sounds, I won't be getting rid of her. Just would like to know what it is I actually have.

Thoughts so far:
My first 6L6 amp. Something special to the notes. Hate to use practically meaningless buzzwords but a sweetness, almost. Even at low volumes. This could pass as a "bedroom" amp, despite the 35 watts. The volume pot taper is much more manageable than the Deluxe Reverb. That thing is as loud as it gets by 3.5 and just adds breakup thereafter. This just keeps getting louder as you turn her up. Doesn't really break up until pretty much 9-10. So far I've most enjoyed the tones plugging in to input 1 of the Vibrato channel with the bright switch off, jumping input 2 of Vibrato to input 1 of Normal, and having the normal bright switch on. Absolutely beautiful cleans and gives an OD pedal some presence. Really love it with a Les Paul and an SG Jr. Have to switch both bright caps off to use a Tele. Only complaint is the tremolo is too fast even on 1 and too weak even with depth on 10. Will have to have someone look at that for me.

Anyway, really excited to have her. Thanks for your help in advance. I'm hoping to do some smaller local shows with it soon. Rock on.

 

[Phrygian77]

Based on the chassis, PT, and choke, it is definitely a '63.

 

[Phrygian77]

I've never seen an early transitional Tremolux from that period, so I don't know what an AA763 would look like. What Fender actually put in the amps vs. what he put on paper didn't always match up during those periods. The 5F6A is a good example of that, and the early 6G Professional Series amp are like that also. Your amp has an extra cap in the tone stack that is interesting. On paper, that cap shouldn't be there in either circuit.

 

[zook]

That amp is very clean and original, beautiful.

The OT is a the correct replacement for a Tremolux.

 

[Wally]

Based on the tube chart date code…ML….it is from December, 1963. It is an AA763. There is a 56K cathode resistor on the V3, P8 cathode. That changed to 100K in the AB763.

 

[Dana Rudd]

Congrats on that fine looking amp. Have fun with it. HNAD.

 

[archetype]

They really are fine heads. I had a black panel Tremolux head and it sounded and acted as you describe it, although mine started to break up a bit earlier. Back then I couldn't find a matching cab for it, so I played it through a Rickenbacker 4 x 10" loaded with some kind of alnico Jensens. That cab gave the tone a surprising amount of low end.

The circuit is essentially a Bandmaster, but with 410 Volts on the plates instead of 440 Volts and a tube rectifier for slight sag. It should be an AA763 no matter what the thing looks like externally.

Number One Task is getting it serviced. Unless you have an invoice in-hand that shows capacitor replacement within the last decade, you're in the danger zone with those electrolytic caps.

A way to change the tonal character and possibly get earlier breakup is to pull the GZ34 rectifier and use a 5R4GB or similar. The GZ34 has a 10 Volt drop, but a 5R4* has a 60-67 Volt drop. There is no upside to using a new production rectifier. NOS is cheap, readily-available, and should last the life of the amp. Your tech should rebias after the rectifier swap.

The other way to get earlier breakup and preserve a bit more of the scooped character of the tone is to use an attenuator, like one of the Weber Mass units or similar. A 50 Watt attenuator will do the job if you're not cranking the amp. If you need to run the amp loud, most of the time, I'd use a 100 Watt attenuator so it isn't stressed.

I now have a brown panel Tremolux 6G6-A into a reproduction J. D. Newell 2 x 10" Tremolux cab with a Weber 10A125 and Blue Pup speakers. It's a little blaster with more midrange than the black panel Tremolux has. I'll give it a 1/3 open back, because I like that kind of sound in the room, and two Weber Signature 10A-S speakers to get closer to the old-school Jensen/Oxford tone.

 

[schmee]

That is one clean amp! Nice.

 

[hotcoffeenochill]

Based on the tube chart date code…ML….it is from December, 1963. It is an AA763. There is a 56K cathode resistor on the V3, P8 cathode. That changed to 100K in the AB763.

Thanks Wally, appreciate the insight.

 

[hotcoffeenochill]

way to change the tonal character and possibly get earlier breakup is to pull the GZ34 rectifier and use a 5R4GB or similar. The GZ34 has a 10 Volt drop, but a 5R4* has a 60-67 Volt drop. There is no upside to using a new production rectifier. NOS is cheap, readily-available, and should last the life of the amp. Your tech should rebias after the rectifier swap.

I don't think I'll be looking to change it's character at all right now. Really happy with the sound.

I do have the Weber MiniMass, but because of the Tremolux's volume taper being so reasonable and using a pedal for OD, I haven't felt the need to use it. It's the only way I can play my Deluxe Reverb in the house, however.

I will definitely be taking it to a tech soon. I have no real info on it's servicing history. The seller didn't even realize (again, allegedly) that he had a non-original output transformer until I had him pull the chassis when I was checking it out.

 

[kuch]

Nice amp!!

My 1st amp was a 62-63 Tremolux with the dark grill cloth. Sweetest sounding amp ever. It was back in 68/69 so it came with the original 2x10 cab. I played a 63 Sunburst Jag and they paired really well together. If you get a chance, try it through 10's. I've been hooked on the sound of 10's ever since. My bandmate in those days had a 64 Bandmaster and imho the Tremolux sounded so much better....
About 12 years ago, I scored a BF 65 Tremolux with the original cab also and that sounded just as good. Eventually realized that I don't need/want that much amp so I "settled" for a PRRI. I'm happy.

The ones I've owned had the sweetest "sparkling" tones ever that had just the right amount of "crunch" when turned up. I think they sound best with single coils.

Enjoy!!

 

[Phrygian77]

I will definitely be taking it to a tech soon. I have no real info on it's servicing history. The seller didn't even realize (again, allegedly) that he had a non-original output transformer until I had him pull the chassis when I was checking it out.

You didn't have any pictures of the filter caps under the cap pan, but my guess is they've been done since the cathode and bias caps have been replaced.

 

[hotcoffeenochill]

Nice amp!!

My 1st amp was a 62-63 Tremolux with the dark grill cloth. Sweetest sounding amp ever. It was back in 68/69 so it came with the original 2x10 cab. I played a 63 Sunburst Jag and they paired really well together. If you get a chance, try it through 10's. I've been hooked on the sound of 10's ever since. My bandmate in those days had a 64 Bandmaster and imho the Tremolux sounded so much better....
About 12 years ago, I scored a BF 65 Tremolux with the original cab also and that sounded just as good. Eventually realized that I don't need/want that much amp so I "settled" for a PRRI. I'm happy.

The ones I've owned had the sweetest "sparkling" tones ever that had just the right amount of "crunch" when turned up. I think they sound best with single coils.

Enjoy!!

Thanks! The purple cab under the Orange is a 2x10 but it's wired for 8-ohms. Probably would be okay to run with the Tremolux but I haven't built up the guts for it yet. Perhaps I'll have to order some new 10" speakers.

 

[prairietelecaster]

...delete. My blather had nothing to do with the op questions. Cool amp!

 

[Wally]

I had to look up that EIA code for that OT…Grand Coil Winders in Grand Haven, Michigan.

 

[hotcoffeenochill]

I had to look up that EIA code for that OT…Grand Coil Winders in Grand Haven, Michigan.

Yeah there isn't much info regarding the OT. I may reach out to the company and see what else they can tell me. It does appear to be correct, as another user pointed out. But I'd still like to know what I'm working with.

 

[Phrygian77]

@Wally I don't know if you saw my post, but I'm curious if you've seen those extra caps in the tonestacks before?

 

[Wally]

@Wally I don't know if you saw my post, but I'm curious if you've seen those extra caps in the tonestacks before?

@Phrygian77 ….good eye…and no, I don’t recall seeing that extra cap; but we see them in both stacks here, don’t we? And…now that we have eyes on in that area, what is that ‘extra’ resistor sitting in between the plate resistors in each channel….and to what do they connect? I can’t really see the value….220K? It would be of interest to document this circuit if one had it on the bench, it seems to me.

 

[hotcoffeenochill]

@Phrygian77 ….good eye…and no, I don’t recall seeing that extra cap; but we see them in both stacks here, don’t we? And…now that we have eyes on in that area, what is that ‘extra’ resistor sitting in between the plate resistors in each channel….and to what do they connect? I can’t really see the value….220K? It would be of interest to document this circuit if one had it on the bench, it seems to me.

Oh fun! A mystery!

 

[Paul G.]

A way to change the tonal character and possibly get earlier breakup is to...

OP never mentioned wanting to change tonal character, nor was "early breakup" mentioned. I have no idea why that is always the goal. I can't be alone in enjoying a sweet-sounding, clean toned amplifier with character.