black stripe ultra in the hands of frankenstein

[marinebassplayer]

i have one more switch in my possession, what can i do with it???


the list of mods i have tried:
a 3 way switch on c-3
the r7 resistor bypass "boost" mod
the mid sweep
r1,2,3 changed to 150 ohms
r10 between stock 10k? and 470kohms (removed)

 

[bot]

Have you tried anything with C6?

 

[marinebassplayer]

no i have not. its a 1uF (if im reading it correctly) what did you have in mind for its replacement?

 

[SacredGroove]

i have one more switch in my possession, what can i do with it???


the list of mods i have tried:
a 3 way switch on c-3
the r7 resistor bypass "boost" mod
the mid sweep
r1,2,3 changed to 150 ohms
r10 between stock 10k? and 470kohms (removed)

R10 won't do a whole lot for you. You may notice a loss of some high end with a higher value resistor there, but on the Ultra R10 is probably the last place I'd think of trying to improve/alter tone, unless you have cap across the resistor.

R7 is a Grid Leak resistor. It's often referred to as having a "boost" quality because it's ability to be removed. When R7 is removed, there is a disconnect from ground, therefore, all signal present before R7 will be retained and allowed to pass, but only on certain pcb's, including the Ultra.

 

[marinebassplayer]

i have one more switch in my possession, what can i do with it???


the list of mods i have tried:
a 3 way switch on c-3
the r7 resistor bypass "boost" mod
the mid sweep
r1,2,3 changed to 150 ohms
r10 between stock 10k? and 470kohms (removed)

R10 won't do a whole lot for you. You may notice a loss of some high end with a higher value resistor there, but on the Ultra R10 is probably the last place I'd think of trying to improve/alter tone, unless you have cap across the resistor.

R7 is a Grid Leak resistor. It's often referred to as having a "boost" quality because it's ability to be removed. When R7 is removed, there is a disconnect from ground, therefore, all signal present before R7 will be retained and allowed to pass, but only on certain pcb's, including the Ultra.

and thats why i put r10 back to stock. the reason why i tried that one was looking at the excel file with all the values on it and i was aiming to create a grail. but after trying it and realizing i missed a small detail. im working on the wrong pcb. :x

now back to the cap on r10 idea. what value range would you put there???

 

[SacredGroove]

now back to the cap on r10 idea. what value range would you put there???

Like I mentioned before, it's not the place I would go to mod. But, if you want to try something there you could use your 470k resistor or a 1M resistor with the combos below. The higher the resistor, the more attenuation on the freq's below the cut-off freq.

500pF//470k=677Hz
470pF//470k=720Hz
250pF//470k=1.3kHz

250pF//1M=636Hz
220pF//1M=723Hz

 

[marinebassplayer]

Like I mentioned before, it's not the place I would go to mod. But, if you want to try something there you could use your 470k resistor or a 1M resistor with the combos below. The higher the resistor, the more attenuation on the freq's below the cut-off freq.

500pF//470k=677Hz
470pF//470k=720Hz
250pF//470k=1.3kHz

250pF//1M=636Hz
220pF//1M=723Hz

if im understanding this right, this would affect lower mids and bass. what would be the the combination for ~250 hz? im curious to what the formula is that your using for this as well. my rm100 has always sounded dark to me and im using the mxr 10 band to cut 125 and 250 hz to clean up the bottom end.

i think that c6 is gonna be my next change but im curious to what the r10 cap would do....:wink:

 

[SacredGroove]

Those are all high-pass filters, so maybe they would benefit you with your low end issue?

The freq's above the cut-off freq. will be retained at full gain at that point in the signal. The freq's below the cut-off freq. will be attenuated, or lowered in gain allowing for the signal to retain more highs, and high mids.

The formula for freq. in this instance is: f = 1 / 2pi(RC)

What's your plan for C6?

 

[marinebassplayer]

not sure yet. im still looking around the forum and the excel doc to see what i could try. if you have a suggestion or a value range on what i could put there that would be awsome.

 

[bot]

I believe .68, 1.0, & 2.0 are common values.

 

[marinebassplayer]

sweet. tomorrow is payday so i will grab some replacements and have some fun with c6.

on a unrelated note, this is post 10 for me. yay

 

[marinebassplayer]

well i finally got some time to mess with c6, funny how a new kid will put all your hobbies on hold for 2 months. i couldn't find anything smaller than a 4.7 to replace the 1.0 that was installed (radio shack has a great selection)

so i put the 1.0 and the 4.7 in series to make a .82. i like it but it makes some noise. i might put it on a switch and to cut the 4.7 in and out of the mix. any thoughts??

 

[Ryzakk]

I still have no spare time and my kids are no longer new! :lol: plus I think I'd tinker more than play-and that scares me!