Idea For Shaka Tube

[Paul Marossy]

I used a 0.01uF cap to ground on the output on my last Shaka Tube build, but I feel that sometimes there is still too much high end and that it could have a little more lows. Has anyone tried changing the three 0.01uF coupling caps to 0.047uF or 0.1uF instead? I'm thinking this would give me more bass. Whaddya think?!

[aron]

It will work. You can try stringing resistor+caps to ground on the end or even, buffer->resistor/cap to ground multiple times.

[Paul Marossy]

A buffer on the output, huh? I haven't seen that suggestion before. Would that tame the highs or ?

[george]

I've toyed with the idea of just a buffer (with no resistor/cap to ground)...

I noticed my Shaka variant sounded smoother running through my AD-3208 with the delay level turned right down, effectively going through the AD-3208's JRC4558.

However I'm quite happy with the way it is now (with no output buffer):

.01 uf between op-amp and first valve stage -> .02uF
.01 after second valve stage -> .015uF

I also don't have any bypass caps on the valve cathode resistors, because I felt it was too bassy with them in.

I also replaced the 100K tone pot with 10K fixed resistor and 10K pot, and made the tone cap .047uF (because .01uF didn't do anything).  The tone control is a LOT less touchy now.  I also tried a 100K fixed resistor between the output cap and pot, but this made it a bit too bassy (ie muddy)

hth ... maybe just bumping up the tone cap from 0.01 to 0.047 may do the trick?

[Paul Marossy]

maybe just bumping up the tone cap from 0.01 to 0.047 may do the trick?

I was just thinking that while I was reading your post, george. I think I may try this first. Thanks for your insight on this one.  

[george]

no probs Paul!

I've futzed with mine for ages ... I'm thinking of putting switches all over it to switch between different coupling cap sizes,  switch cathode caps in and out :lol:  - just so it's *fully* adjustable .... :lol:  

cos I'm sure in a week's time I'm going to think "no it's just a bit *too* muddy on the neck pickup"  :?

[aron]

Yes, just increasing the value of the cap will work. I keep wanting to try Mark's idea of increasing the "poles" of the filter.

[Paul Marossy]

I'm thinking of putting switches all over it to switch between different coupling cap sizes, switch cathode caps in and out  - just so it's *fully* adjustable ....

I like versatility, too. Well, up to a point...  :wink:

[mlabbee]

Try coupling caps .022 or larger
Try putting the tone stack between the first and second stages (you may need to bump up the gain a little)
Try a Baxandall tone stack (see Adam's amps for a good article on tone stacks).  I've played around a bit with Baxandalls and I like them much more than anything else I've tried (although the insertion loss can be significant).

[Paul Marossy]

Yeah, I seem to like 0.022uF coupling caps best from my other tube projects.