Rocket (VOX) - Odd Tone Stack Behavior

[RJ Guitars]

Have any of you ever looked at the behavior of the Rocket (or VOX) tone stack behavior using the Tone Stack Calculator on the Duncan Amps page? A friend pointed this out to me recently that just as you max out the bass pot you get a huge dip in the mid frequencies.

I swear I can actually hear it on my Rocket build... Recalling conversations over the last few months, I think Angelo asked me if I had noticed a weird notch in the tone when you max out the bass control and I never got around to a thorough test of it - good ears Ange!

If you are not familiar with the TSC, it's a free download on the Duncan Amps site and it's just absolutely a cool piece of work... and something you should find greatly useful

http://www.duncanamps.com/tsc/index.html

Watch the sonic spectrum as you go from 95% max to 100% max on the bass control... weird!

rj

[nickt]

Hi RJ

Try rolling both bass and treble back to zero. What you should get then is pretty much a flat response.

Having used an AC30 setup like that for the last 30 years I was interested to find my "standard" setup basically took out the tone stack. I did the experiment a year or so ago with Duncan's simulator.

One thing it could explain is why folks like the pre-top boost AC30's so much.

cheers
Nick

[RJ Guitars]

Hi RJ Try rolling both bass and treble back to zero. What you should get then is pretty much a flat response. ...cheers Nickt

Thanks Nickt - That definitely levels out the spectrum. I am curious if the result is the same if you were to just take the tone stack out altogether? Two less knobs and all the coolness of the Rocket, sounds tempting.


You can double click on the components in that TSC and replace them with different values. If you replace the 10K resistor with a higher value (I like 18K) you can get a nice mid boost... or in fact run the Treble and Bass down to zero like you say and put in a 100K and you get that same flat signal but a monster signal boost... cool stuff!

rj

[nickt]

Glad you found it useful

I did my testing in the context of messing with my Lightning clone trying to turn it into a 1/2 Rocket.

This was before your work shook all the apples out of the tree and got the rocket info consolidated (BTW thanks! )

I was trying to sort out the various rumored tone stacks at the time. All of the stacks had a flat response at zero treble/bass but there was a huge difference in attenuation - one was nearly 30db if I recall correctly.

Unfortunately none of my efforts sound anywhere near as good as the original vox

Now all the info is out there I'll have to get back and sort this little amp out.