Rocket w/ Reverb

[amplifiednation]

Those 220k resistors are balance resistors for the two 40uf caps on the bottom, not bleeder resistors.

Mark

I didn't use them on my build. The resistor helps to evenly split the power to the two 40uf series caps, correct?

I gotta get some stuff from Mouser, maybe I'll order them. What function does the 220k have on the ground side of the fiter caps?

[M Fowler]

You don't need them in your TW Rocket.

[angelodp]

I wanted to try adding the mid-pot to this build and did. I am not certain I'll keep it yet.

Adjusted layout... its a keeper.

[IMG1083]http://i260.photobucket.com/albums/ii9/ ... b-rj72.jpg[/img]

[rooster]

ange - Yeah that mid pot thing. I added one, too, but where you chose a 10K and a 25K pot, I chose a 5K and a 10K pot. My thinking was I could pull out some but not all, and add just a little.

Results? Well, I typically put the pot to where it is at 10K.

In the end, given a particular guitar and a particular speaker cabinet, the typical controls will get you where you need to be I think. Er, and sometimes not! And then you could swap power tubes, J/J to Saratov and than spend another day trying to dial it in. I think the AC30TBRocket is one of the most unique circuits ever made, although many times I think it is perhaps not the most versatile. ...No, I will not explain my last comment!!

[angelodp]

Hey Rooster, did you wire it up the same way? So you are indicating that the staple 10k is where you are ending up. Noon on the pot in any case is that 10k value. I do like to boost a little for my Tele. Do you think that the addition of the mid-pot alters the circuit in any significant way?

[Zippy]

ange - Yeah that mid pot thing. I added one, too, but where you chose a 10K and a 25K pot, I chose a 5K and a 10K pot. My thinking was I could pull out some but not all, and add just a little.

Results? Well, I typically put the pot to where it is at 10K.

With what guitar(s)? When RJ and I were tweaking on the first several Rockets that he built, we both enjoyed the extra bit that the MID control provided. I tend to prefer single coil guitars (ala Strat, Tele, and P-90s). RJ has a few humbucker guitars as well.

I think the AC30TBRocket is one of the most unique circuits ever made, although many times I think it is perhaps not the most versatile. ...No, I will not explain my last comment!!

What amps do you consider more versatile? I'm trying to understand what kind of music you play. We've certainly found it very friendly to pedals.

Hey Rooster, did you wire it up the same way? So you are indicating that the staple 10k is where you are ending up. Noon on the pot in any case is that 10k value. I do like to boost a little for my Tele. Do you think that the addition of the mid-pot alters the circuit in any significant way?

If the MID is dialed to a circuit equivalence of 10k, there is no difference. Adding resistance boosts the mids - that's about it.

What are you thinking might be altered?

[angelodp]

Hi Zippy, just wondering if the addition of the midpot alters the general frequency characteristics of the circuit, beyond being able to control the mids. AFAICT it does not seem to change the basic sound of the amp.

Best A

[rooster]

OK, with my 5K in place, I added the 10K pot after it. It's audio taper, 20%, so it reaches 5K about 3/4 up - which is then a stock value - and turning it up to full on the amp sees 15K. When I turn it off, the amp sees 5K, of course.

As to sound, well, when you have it at 5K or a few bumps up, I think the amp sounds anemic, losing some high frequency information in the process. Of course you all know what it sounds like at 10K. At 15K, well, it's not much different than at 10K, IMO. Which is to say that the control offers nothing 'surgical' to the mid range section IMO. No, I have never tried 25K.

What I will offer is that the amp is a 'signature sound' amp IMO. If it is a proper working example, then that 'signature sound' is there. If it is not, then, for my tastes, it's not working correctly. Yeah, I know this seems argumentive but then, please consider Ken Fischer and what he offered when he built the Rocket? It's a very stable example of an AC30TB channel. He even went so far down this path that he eventually offered a switchable 220K resistor to ground at the PI cap to duplicate the 'Normal' channel interaction. This is indicative of someone who really appreciated the AC30TB.

As to guitars, yeah, it's been said that Ken liked Teles into the Rocket. Whether he prefered it over all other guitars I can't say. I prefer my SC guitars into it best of all, but I do try to dial in my LPs, too. Frankly, I think they, HBs, are hard to dial in because the amp delivers so much midrange (and bass if you run the wrong speakers, and even then if you are not cautious with the Bass control), leaving you with, sure, maybe a fatass rockin' sound, but maybe not too much 'character'. Having 30% taper pots, running a 500pf bleed cap, and keeping the guitar turned slightly down is what I have to do for HBs (YMMV), when I want the guitar to have something less than a 'fatass' tone.

What other amps do I run? A Fender SR, a '59 Silvertone Medalist, a tweed Champ, two different Express clones (different OTs, 35/25), and an Ampeg 12" equipped early Port-a Flex. Of all of these, I think the Rocket is the one that is the hardest to set up to use with ALL my guitars. And, this said, it prolly has the most signature sound, as well, which takes us back to the top I think. Which is why I say I don't think it is a versatile amp. Instead, and as I said before somewhere, I think it does one thing very very well.

[Zippy]

Thanks, Rooster. I appreciate your detailed response.