67 / 68 / 69 (Super) Lead / Bass for later Jimi, Led Zep,etc

[VintageCharlie]

Btw., could i stick with the Drake 80 PT for either a Drake 119/132 OT and a Dagnall OT? OR would i have to go with a Dagnall T2562 PT to get the correct voltages for a 68 and a 69 amp? If either of these PT's (Drake or Dagnall) can work well with either Drake or Dagnall OT's, then the transformer choice is half as critical, as it involves gambling with half less money. Afaik Marstran Dagnall PT is 490v, not sure, but i think the Drake 80 puts out the same voltage. Are there any other specs between these two power transformers that might affect the tone? If both are good, then i think i might buy Drake PT, OT and, if needed, change the OT to a Dagnall later on - if i happen to go the 69 route and circuit tweaks towards it aren't enough. I think there shouldn't be a big problem to sell a good slightly used Marstran OT without too much loss of $.

One last thing - putting the power caps on top of the chassis would probably make tweaks much easier and the whole design more flexible, but aren't there any bad side-effects - the caps being close to transformers, etc.?

[bulatovic]

My opinion is that the OT would somewhat colour the sound, create the tonal basis, but again the main things to tweak the amp are resistor/cap values. If going with '67 i'd definitely go with 2" Drake. Actually, if i was building a 100w now, i think i'd choose the 2" drake regardless of the amp - as long as it's '67, '68 or '69 spec...

'67 is more gainy than the 45/100, but to my ears not nearly as gainy as a '68 or a '69, but a lot sweeter and more "round" if you get what i mean. However it can get really barky when you turn up the mids and treble and add a bit of presence, with a nice PAF-like humbucker it does miracles!
a '68 is a lovely amp, got that "spongy" saggy thing to it and really sounds great when cranked up, but to my ears still a bit on the bright side, '69 is more of the same, just feels more powerful and punchier due to the filtering. Another thing to mention - if you're using pedals, i am quite sure that a '67 would be a better platform for those...

so my verdict is - a '67 spec with:
-0.047uf or similar PI coupling caps
-470k - 470k/500pf mixers
-100pf bright cap
-Shared V1 cathode (820r/ anything from 50uf - 200uf cap)
-a switch on the back for V2a bypass cap 0.68uf to boost the mids, and maybe also, on the same switch - 2 in 1 tonestack (you'd need a 3pdt for that) - Up: Bass tone stack, no V2a bypass cap, down: Lead tone stack + 0.68uf V2a bypass cap
-maybe a bit higher filtering for stiffer feel and more punch and less sag - something like 100/50(32)/32/32/32 (mains/screens/pi/preamp/preamp)

but that's just my 2c

-as the matter of fact i am building a 50w based on the things above, just with 0.039uf PI and 0.018uf preamp coupling caps, and 32(64 switchable)/32/32/32+32 uf filtering and a tube/ss rectifier switch...

[VintageCharlie]

Thanks Luka,

btw. a 50w is something what i haven't ruled out completely yet too, as this 2nd amp is meant to be more of a "lead" amp while the 45/100 a rhythm-machine. And for lead the 50w's sound great afaik. One of the things to like about them is supposed to be more dirt or gain and earlier, more compression. On the other hand compression is something one can add even with a good quality studio compression VST plugin to the recording, but you can't get it out of there once the amp does it on its own. (though the amps compression is probably much better sounding than any what so ever hi quality VST plugin can do). But on the other hand, a 50w doesn't seem to be able to get that BOG thing going on - it doesn't have that amount of punch and headroom (on a recording it seems to be able to come close though).

[Roe]

Thanks for this reply Roe, it was very helpful. Btw. the 67 can sing easily without pedals, right? - it has quite some more dirt and gain on tap than the 45/100? - like a dimed 45/100 would have the same dirt as a 67 on 7-8 or something like that?

I will do some more critical listening on my own and i hope some other guys can jump in here and share their experiences - 67 100w lead/bass vs 68/69 100w lead/bass Marshalls for Bog and Led Zep.

Best regards,

VintageCharlie

a 67 doesnt sing easily with a strat no. you need to work quite a lot without pedals unless you are playing real loud

[bulatovic]

In that case, since you said you want an amp for more lead stuff rather than rhythm go with a '69.
Try playing around a bit with the preamp - remove the bright cap (volume pot), use 0.022uf on the bright channel coupling cap rather than 0.0022uf, try having a shared cathode on V1 and that just might be the key

[VintageCharlie]

Btw. here's Rock me Baby on a early metal panel JMP-50 lead spec:

http://www.youtube.com/user/vintagetom# ... -tDcz1iPZs" onclick="window.open(this.href);return false;

that guy is a fantastic player and under his fingers the JMP-50 gets quite close to Hendrix's tone.
Oh and here some clips from the Plexi335 guy on Youtube. A late 60's JMP-50 bass spec:

http://www.youtube.com/watch?v=KqsVmvbi4DM" onclick="window.open(this.href);return false;

and a 69 Super Lead:

http://www.youtube.com/watch?v=f9KVRiHr ... re=related" onclick="window.open(this.href);return false;

I suppose the "67" JMP-50 might really be a 69 as the description speculates, as it sounds quite edgy for a bass spec.
These were the clips i was referring to when i meant that a jmp-50 doesn't sound that much different to a 100w - what i hear when these are compared (thoug h the comparison is not really fair as the 50w is a bass spec and the 100w is a lead): the 100w is less compressed and more open sounding, it has a tad more clarity, but it is also almost piercing on the attack. They sound surprisingly similar, to me at least.
So i'm still wondering about the 50w option too. I suppose what a 50w can't manage, which should be very audible live, is the punch and impression of a huge size of the 100w due to it's bigger headroom - it has to be a massive sound compared even to a 50w. I suppose in this regard, despite it's bigger size, more tubes, bigger trannies and hence slightly more expensive price, the 100w is more versatile. I guess if a more compressed sound (a la the 50w) is desired one can get the compression by other means and the edge on the 100w can be taken off by lowering treble and presence controls. But with a 50w you can't get the same cut and headroom if desired. OR am i completely wrong here?

[neikeel]

I personally usually use a humbucker guitar with coil split. The strat for a bit of Jimi noodling or funk stuff.

I really like the 68 SL. The amp is not bright or harsh (totally stock with 5k bright cap etc) it runs Mullards throughout with M8137 in PI. I find it will do Led Zep Jimmy Page very well at 3-4 on the dial and if you crank it up to 7-8 you head for VH tones. It does not have that thick percussive with a strat that you get with the 66 or 67. I find most 70 and up superleads too bright and aggressive - they have to be tamed. The 68 is actually quite forgiving of my relatively sloppy (blame Jimmy Page ) technique.

[VintageCharlie]

Just heard Udo Pipper playing Sleepy time time on his JTM-45 on youtube and compared to the tone on the record i can say for sure that in this case, to my ear, the 45/100 is hands down the winner (though there are many other variables in the equation involved). The JTM-45 sounds fantastic, no question, but in this case the 100w has more of everything. The 45/100 is also very smooth, but sounds huge and has a fantastic attack and really makes the guitar get a cello-like tone. If this also translates to the JMP-50 vs JMP-100 question, then i think i might rule out the 50w for my choice.


p.s. And spoonful is simply godly (i hope it's really a 45/100 )

[Roe]

the 68 is very popular around here, partly because of evh. personally I prefer the 69 - the chassis is better and the amp is tighter and more responsive. its not harsh or stiff with good tubes and caps (e.g. sozo super cap)

[shakti]

p.s. And spoonful is simply godly (i hope it's really a 45/100 )

Spoonful is the quintessential JTM45/100, don't worry.

[shakti]

the 68 is very popular around here, partly because of evh. personally I prefer the 69 - the chassis is better and the amp is tighter and more responsive. its not harsh or stiff with good tubes and caps (e.g. sozo super cap)

In your experience, which one would be better suited for a Band of Gypsys tone? I had just about decided to build a '68/12-series, but am a bit torn...I doubt that I'll build one of each, since they basically only differ in the filtering.

[VintageCharlie]

Thanks Thorleif, good to know!

[VintageCharlie]

Btw., Thorleif, how does your black flag handle BOG stuff - is it far away from that tone?
IIRC Gutpile once told me that a even a 45/100 can perfectly do BOG tones - hence i'm curious - a 67 or Black Flag should be capable of that too. I asked him if he could share some clips, but they were buried somewhere in his PC. But, hearing what a great player he is, i believe it's true, when it comes from him (though again ,it might be a subjective thing if a tone is spot on or just an approximation).

[Roe]

the 68 is very popular around here, partly because of evh. personally I prefer the 69 - the chassis is better and the amp is tighter and more responsive. its not harsh or stiff with good tubes and caps (e.g. sozo super cap)

In your experience, which one would be better suited for a Band of Gypsys tone? I had just about decided to build a '68/12-series, but am a bit torn...I doubt that I'll build one of each, since they basically only differ in the filtering.

too be honest, I'm not sure. the 68/low filtering gets a good jimi tone for sure. I like the higher filtering for riffing

[VintageCharlie]

Hi guys,

Brian told me that the 1203-80 and T2562 are interchangeable, as the voltages are practically the same. So i could use either of them (in this case i'd choose the Drake - just because to me "older, bulkier = better" ) and then switch the OT if i end up wanting a proper 68 or 69 spec and if i feel the Drake 119 or 132 doesn't deliver what's needed for that (though i suppose the circuit changes should be enough and such a hybrid build might sound equally great, just with a tuch less harshness maybe).

So for now i settle with the idea of something like this:

- My leftover 45/100 alu chassis
- Drake 80 PT and probably 132 (instead of 119) OT
- Starting with '67 specs and then, if needed, trying out '68 and maybe '69 or simply including some aspects of the later circuits, like gain increase, etc. (filtering, tone stack, treble cap, split cathode arrangement evolutionary incarnations)
- Caps probably under the hood - maybe even the one that is usually on top in 67 and upwards amps - it could be mounted inside on the side of the chassis - just as with JTM-45's i suppose?
- some small mods on some push pull pots - for different bright cap values, changes in tone stack (lead / bass) or something like that (actually this would be mostly for A/B testing - i might go back to one value without the mod after i hear the differences live) - nothing fancy or complicated.

So it probably will end up either as a stock 67' or some sort of hybrid. And if wanted it might even end up as a stock 68 or 69. Apart from the chassis - might sell that one and go for a steel chassis for the build after all, but that depends on what is going to happen with George's shop. Ceriatone would be an alternative for the time being, but i have no clue how the mounting holes for trannies, etc will/won't line up with Marstran and other parts.

Btw. if anybody from Europe (this would make most sense as i've paid for the expensive shipping to Europe already) is interested in a Metro 45/100 alu chassis, i might sell mine to get a more "correct" steel chassis for a '67 or later amp. But i'm still wondering - maybe alu chassis is better though not being "correct".

Thanks for all your input and help guys! I'm still very interested in any input in regard to 67 vs 68/69 spec 100w amps and their suitability for BOG. With Led Zep, after listening more closely and after what Roe said, i have to agree that to get it spot on, the 69 SL is the only ticket - it's really an edgy, cutting and relatively stiff tone that a 67 doesn't fork out (maybe a 68 comes close).

Oh, one last question what are the values of all the filtering stages (and how each of the stages are designated and in which order you list them?) in a 45/100, a black flag, a 67, a 68, a 69 100w (i know it varies much, but i mean, in general)?
As i have minor understanding in electronics, i'm not sure, but from what i gather (i'll list them from left (beginning with the preamp) to right (to the mains?):

45/100: 8-32uF (preamp) / 32uF / 32uF / 32uF / 32uF
JTM-100: 16-32 (preamp) / 50uF / 50uF / 50uF/ 50uF
'67: 32-64 (preamp) / 50uF / 50uF / 100uF / 100uF? (this one is definitely totally wrong - i'm just guessing from the caps i see on the board)

Would be great if somebody more knowledgeable could chime in and complete/correct the list up to a '69 spec, or share a link to such a list - couldn't find one.


Thanks!

Make it a great day!

VintageCharlie