ab165 bassman with EL34's

[joelap]

Re: ab165 bassman with EL34's

A more modern sounding JMP is a JCM800. That was basically the theory behind the evolution of Marshall amps. Look into a single channel JCM800. The models are 2203 and 2204. If you want 2 channels, 2205/2210 but be advised the channel switchers have plate follower tone stacks (more like a fender style tone stack) and the 2203/2204 have Cathode follower tone stacks like the JTM/Plexi Marshalls. Not to mention the mods available for JCM800's are everywhere, tons of DIY mods too.

 

[drew_half_empty]

Re: ab165 bassman with EL34's

more modern isn't really what i'm going for, though

look, i'm not looking for a marshall, and i'm not looking for a bassman, i'm taking a bassman that has a good gain stage & making it into something totally new

a lot of people, well a couple on here, way back in the day said that when i finally got around to building my own amp, it wouldn't be a copy of anything out there, it'd be something new, and that's true. I'm way too much of a picky ass to pick one amp out there & say "this is the tone i'm going for", and now i'm finally getting around to building my own amp to match the tone in my head. Look at how long it took me to nail the last one, but i got it done, and IMO it sounds great.

this time i'm taking the much, much less expensive route. I can build one for about $500-600 (from the ground up), and have about 4 friends i can get help from.

all i wanted to know was if anyone had done the basic operation & what it sounded like, so i know where I'm gonna be working from. Sorry if it frustrated you

 

[CapoFirstFret]

Re: ab165 bassman with EL34's

I tell you what Drew...it may be beyond your abilities...I know it's far beyond mine but Scott or Jeff could give you the specifics. If you could take the idea of the Mesa/Boogie Blue Angel which uses 2 6v6's and 4 el84's and can be used in either mode or blended...maybe an amp can be built that does the same thing with EL34's and 6L6's. That seems to be what you're after. A circuit that can use either/or and has the option of blending them would be very interesting. Just some food for thought!

 

[drew_half_empty]

Re: ab165 bassman with EL34's

wow, never thought of that

yeah, i could use like a blend pot or something like that to go back & forth between the EL's & 6L6's

Jeff is getting a PM, this is a great idea, thanks much, man

 

[Benjy_26]

Re: ab165 bassman with EL34's

The easiest (though not quite inexpensive) way to go about doing what you want would be to get a preamp with the voicing you're looking for and running a stereo power amp with different tubes into a pair of dissimilar speakers. Maybe a Triaxis/50:50 setup would work for you. Write your preamp settings and run one side of the power amp with EL's and the other with 6L6's.

 

[drew_half_empty]

Re: ab165 bassman with EL34's

both the ab165 and jmp ballpark it

nothing else comes close

nevermind, i'll just build it & post some clips when i get done, ok?

 

[Quencho092]

Re: ab165 bassman with EL34's

I think that Benjy had it right, drew.

You seem to like a beefy power range, say around 50-100 watts. You might like your sound alot better if you built a BF tube preamp and just ran it into a tube power amp consisting of EL34's. You could choose to go mono and just run 2 El34's, or just run the whole stereo rig.

The other thing is that this would allow you to tap into more of your varying tastes more easily. From what i remember, you've always liked bassmans, but your tastes have changed slightly from that mold.

The kind of sound that you're looking for seems, to me, to be like something that paul rivera would have done, except for the bassman instead of the princeton. Didn't mesa boogie get started with him hot rodding a princeton with a big magnet speaker, big trannies, and some other goodies? Sounds almost like you want the Mesa Boogie version of the BF bassman-more gain, better components, power tube type switchable, and simply tighter sounding.

 

[drew_half_empty]

Re: ab165 bassman with EL34's

nah, not higher gain, and not THAT much tighter sounding

I'll just build it & post clips when i'm done

 

[Hot _Grits]

Re: ab165 bassman with EL34's

Of course, you could run two amps...

-but I like the Blue Angel 34/6l6 idea. though the BA doesn't offer variable blending. If you could get that happening you could be onto a major breakthrough in amp design...

 

[Quencho092]

Re: ab165 bassman with EL34's

anyone ever tried this? seems like (with a few additions like a mid knob, presence knob, and a blend pot to act as a gain control) it'd be one hell of a rock amp

What you're suggesting is the same thing as setting a master volume. A gain control would be just that, and the stock volume control becomes the master volume. In other words, you're trying to dial in more preamp gain, because non master volume is the equivalent of using your pre as volume and post dimed (minimum gain)

What you want is just a 1987x with a fender tone stack and gain control. That is what it equates to-EL34 power stage, fender pre w/ gain....

It'd be easier, IMO, to build a 1987x with the fender tone stack and just wire in the gain pot. The only other way i could describe it is that you like the way a marshall crunches, but at the same time preferring the way a fender tone stack 'sounds' and drives a power stage...

 

[drew_half_empty]

Re: ab165 bassman with EL34's

not so much

if i understand right, the ab165 bridges the bass channel with the normal & that acts as a gain stage, that's why they crunch so well. It doesn't make the amp any louder when cranked, cuz you know, 10 is 10, and the transformer/tubes can handle what they can. The whole reason for me wanting to control how much they get bridged together is so i can get the volume of it dimed & be able to controll how much it drives

plus, if i remember right, the ab165 is a lot simpler in design (and therefore cheaper to build), and if i'm going from the ground up, it won't be much of an issue as to where i start.

chops, get off my back

if i did run both types of power tubes, i could put 6l6's in the bass channel, so when i blend them in for more gain i get a more 6l6 tone, but it'd cost more, so at first i'm gonna try to get away with just EL34's

 

[Boogie Bill]

Re: ab165 bassman with EL34's

One option you might like would be a modded JTM45. The tube rectifier gives nice bloom. Clip out the bight cap, and modify the tone stack to give you just a little more bass. Easy to do--just changing one cap. The EL34's still give you that nice snarl.

A 50-watt BF Bassman into a re-wired Marshall 412 with greenbacks is a formidable set-up for classic rock. These have a SS rectifier, so the bass with be tighter, with less sag and bloom. The top end is "airier" and the mid-range has less slice than the EL34 amp.

And, check out Eurotubes for information on his "integrated quads" sets.

Bill

 

[Lake Placid Blues]

Re: ab165 bassman with EL34's

not so much

if i understand right, the ab165 bridges the bass channel with the normal & that acts as a gain stage, that's why they crunch so well. It doesn't make the amp any louder when cranked, cuz you know, 10 is 10, and the transformer/tubes can handle what they can. The whole reason for me wanting to control how much they get bridged together is so i can get the volume of it dimed & be able to controll how much it drives

plus, if i remember right, the ab165 is a lot simpler in design (and therefore cheaper to build), and if i'm going from the ground up, it won't be much of an issue as to where i start.

chops, get off my back

if i did run both types of power tubes, i could put 6l6's in the bass channel, so when i blend them in for more gain i get a more 6l6 tone, but it'd cost more, so at first i'm gonna try to get away with just EL34's

The AB165 is a SF bassman. I've been through these amps thourghly. The AB165 preamp is essentially not different from any other 60's Fender high power tube amp. You will find it's the same basic preamp design regardless of it's a 68 bassman, or 64 Twin (sans reverb), or a 65 bandmaster. The AB165 doesn't have more gain than a BF. Iv'e had one or two. The signals of the two channels on all these amps are seperate until they reach the voltage amp tube just before the signal goes to the phase inverter tube. If you build an amp from scratch, build it based of the 6G6 BF circut as the starting point. The 6G6 has a tube rectifier, and the 6G6A has a solid state rectifier. If you use the 6G6 circut you can swap back and forth from a real rectifier tube and a SS tube replacemet. And EL34's will respond with more harmonic complexity with a tube rectifier. To get more power amp distortion on one of these Fender circuts use a 12AX7 PI instead of the speciefied 12AT7.

Running one channel into the other in series is basically the original Boogie MKI idea, if that's what your thinking.

 

[B2D]

Re: ab165 bassman with EL34's

and my transformer is bigger than a drake transformer, so there.

Bigger does not necessarily mean better. Duuuuuurrrrrr

basically what I'm doing is taking the jtm concept (brit-ified bassman) and jumping it foward 20+ years

...and then you say...

more modern isn't really what i'm going for, though.

Ok... :laugh2:

 

[drew_half_empty]

Re: ab165 bassman with EL34's

Bigger does not necessarily mean better. Duuuuuurrrrrr

...and then you say...


Ok... :laugh2:

silverface bassmans have good transformers


and yes i am jumping the JMP concept foward, but Jim used a '59 bassman as his base, i'm using a late 60's bassman and applying a few concepts of a 70's brit amp

not exactly modern, bro. MORE modern, but not like jcm2000/dual rectifier modern

 

[drew_half_empty]

Re: ab165 bassman with EL34's

well, my 3 main styles are rockabilly - ie brian setzer, psychobilly - ie nekromantix, and stoner rock/classic rock - ie bad wizard

both my guitars are pretty well suited for both.

The '59 is really bright & just a little recessed in the mids so it does rockabilly well, if i go into the mid position with the pearly gate i get a more bluesy midrange & tame some of the brightness

the hot rail is actually an amazingly versatile pickup, as far as rock is concerned. I can get good psychobilly tones, great rock & roll tones, it does have a sort of billy gibbons ish midrange, and it's got a lot of clarity while still being really high output.

the bassman I'm running now with a TS is capable of any of these tones, but i'm wanting something that sounds a little more brit. In other words, it's really good for psychobilly & rockabilly, and it does pretty well on stoner rock, but, for those genres it leaves a bit to be desired, it doesn't NAIL the tone i'm hearing in my head

the tone in my head is a cross between a jmp and an ab165 bassman, and i've been wanting to build an amp anyways, so it seems like the obvious choice

describing this tone, hmm...take gibbons' tone on "waitin for the bus", add a TINY bit of the tone on "jesus just left chicago", not so much the strattyness but the "blue grit", and that's pretty close i suppose

or just imagine a JMP mixed with an AB165

 

[JeffB]

Re: ab165 bassman with EL34's

but i would also like to own a jmp and a jtm45 at some point

but once again, neither are what i'm really going for, even though the JMP comes real close

Drew,

I really think if you got yourself a JTM45/BB/Clone..whatever...and kept the tube rectifier and had it rebiased for EL34s or KT88s or something..you would find your tone....the "sag" & other general charecteristics of the bassman with a bit more gain and the middy complex crunch added by the brit tubes.

 

[Vasshu the humanoid typhoon]

Re: ab165 bassman with EL34's

20 years later...it is still the same
Hehe never ending story.