Advice needed on Concentric stack knobs!

[davebass66]

Hi guys, just wondering if there are any folks out there with experience of using a jazz bass with the stack knob controls? reissue or original of course!

I've just started to build a bitsa Jazz (ordered my sonic blue body today)! which is gonna look a lot like the early 60's style and really like the idea of the stack knobs, however I can't find that much info on them from users, and what I have read has involved people reporting problems with low output because of the 2 resistors. Have also read that there is a loud hum if you solo either of the pickups. Is this a standard problem or could it be unique to the owner?

Obviously at the end of the day I want the bass to sound as good as possible and if that can only be achieved by using the TTV config then I will, but would definitely like to find out more info on the stacks first!

Also I notice that it is a lot more expensive to buy the stack knob config, is this just because they are less commonly used?

Thanks in advance!!

Dave

Edited August 13, 2012 by davebass66

[ikay]

[quote name='davebass66' timestamp='1344877596' post='1770549']
... people reporting problems with low output because of the 2 capacitors ...
[/quote]

This post on talkbass (about halfway down) explains the technical factors relating to the two extra isolating resistors in the VT VT circuit which result in slightly lower output and some loss of high frequencies compared with the standard VVT circuit - [url="http://www.talkbass.com/forum/f38/stacked-tone-volume-jazz-bass-401694/"]http://www.talkbass....zz-bass-401694/[/url]

Edited August 13, 2012 by ikay

[davebass66]

Thanks mate, I'll have a read through it!

[KiOgon]

I'm very happy with my AV '62 Ri Jazz, no problem with output compared with everything else & plenty of tone variation on both pups.

I have stacked pots to fit in my Frank Bello but I've been lazy & not got around to it yet

Cheerz, John

[davebass66]

[quote name='KiOgon' timestamp='1344886534' post='1770709']
I'm very happy with my AV '62 Ri Jazz, no problem with output compared with everything else & plenty of tone variation on both pups.
[/quote]

Thanks John
Do you get any hum/noise when you solo either of the pickups?

[KiOgon]

No problems at all, everything I play goes through - Fender Gold Cable to TC polytuner into Little Bastard - 4x8 & 1x12. I have a bench magnifier which runs 2 daylight tubes, that can induce 50Hz hum into anything, 'til I off it! From memory the Jazz is no worse than any other & certainly no extra noise with either pick up solo.

The only surprise I got with the '62 Jazz was the stepping on the tone pots, I didn't know they did that! The after market pots I have are just normal, smooth sweep.

[Stacker]

Yeh, the resistors, in the original circuit, prevented tonal loss on one pup affecting the other. Plus, there's an output drop. This is the main reason that Jaco converted his original Jazz to VVT and also why the '62 RI did away with them as well.

Matter of fact, I bought a set of Luxe resistors last year and meant to fit 'em to one my old Stackers. Will give it a go and post back at some point.

[bremen]

[quote name='ikay' timestamp='1344885900' post='1770702']
This post on talkbass (about halfway down) explains the technical factors relating to the two extra isolating resistors in the VT VT circuit which result in slightly lower output and some loss of high frequencies compared with the standard VVT circuit - [url="http://www.talkbass.com/forum/f38/stacked-tone-volume-jazz-bass-401694/"]http://www.talkbass....zz-bass-401694/[/url]
[/quote]

That's a really useful discussion.

The summing resistors will always reduce brightness when used with a long cable. Put a high input impedance preamp* in the cavity or use a wireless sytem and the problem goes away, however.

* I haven't tried this but it should work: http://www.cafewalter.com/cafewalter/fetpre/index.htm

[iiipopes]

The bottom line is that if Fender discontinued the stacks after less than a year of production for both production and tonal reasons, then (rhetorically) why would anybody want to go back to this configuration, especially since the VVT is so much easier to work with, both on stage and in the studio?!

Regarding hum/buzz: original Fender Jazz pickups and their copies are all single coil, and all are prone to hum/buzz/electrostatic noise when used singly. The humbucking effect is best when both pickups are set at the same level. But most people bias one way or the other for their personal tone, so it's a compromise at best. That's what finally turned me off traditional J pickups in favor of the humbucking varieties. I currently run a DiMarzio UltraJazz bridge pickup with my Rick humbucker on my custom fanned fret bass in VVT.

[dan670844]

If it helps I am pure jazz bass I have 2 three knob jazzes and two stack knobs, a reissue and an original. Both stacks have less top end and a smoother rounded tone they also have a better low end definition, if thats your thing then go for it. Great for motown and reggae I guess. Not so good for funk etc. There is not a great deal off difference but there is a difference. If you are looking for that bright punchy bridge for funk I would stick with the three knob. Also With the three knob job there are a wider range of tones. You can emulate the stacked treble roll off on a three knob by rolling of the both volumes equally a little to get the tone bleed, thats basically what all the reggae dudes did like aston family man. I use the stack knobs more because of the necks they both have 7.25" slab board necks. If I have been playing a lot they are godsend they fit you hand like a glove and are very easy to move around and fret. I can get my tone from both styles of jazz, but my core tone is pretty std. I use valve amps( LB30 and CTM300) they both have enough preamp sensitivity to make a jazz sing. I would imagine you have to boost the signal on most other amps to get the signal level right with a jazz to give it a nice tone and punch. If your pickup installation is shielded properly you should not encounter any higher buzz from the stack knob config. As you know all jazzes hum a little when pickups are soloed. If you want to emulate a period correct stack knob they made them between 1960- to mid 1962 the body shape is slightly different and the neck profile is wildly different from later jazzes with clay dots as markers and a huge slab of brasilian rosewood. They are as rare as rocking doo, not because they are the ultimate jazz bass, morever because they were at the time very expensive and the neck design was such that that most of them suffered neck twist and the pots where dodgy so a lot went back to fender for remanufacturing. I guess thats is why they changed to the three knob style. The ulimate jazz bass is for sure the 1963-1965 three knob i.e the one that John Paul Jones played in Zep

Edited August 14, 2012 by dan670844

[davebass66]

Thanks guys, this is all really helpful!

I think I'm going to go for it and fit a stack knob as tbh I have a Jazz deluxe which has been pretty highly modded so if i need a sound with more bite etc I can pick that one up! would be cool to have a nice round vintage tone. Plus, if it doesn't work out you seem to be able to pick up the standard control plates pretty cheap.

Almost everything is ordered now! Will post up pics (for those who might care)! when it's finished...I don't think it's gonna be a perfect era specific build, just going with the early 60's vibe........So.Damn.Excited!

Thanks again guys!
Dave

[LukeFRC]

go into a music shop and try one of the squier jaguar basses with the stack knobs for a wee trial. (common enough that there is likely to be one in your local shop)
I loved the idea of stack knobs till I tried it in practice. Not a clue on the tone differences but it annoyed me enough in a 10 min trial in a shop I went right off them!