Got an nfb question now that I figured out mine works

charvel pointy head · Post by **charvel pointy head** » Tue Dec 18, 2007 10:03 pm

after the revelation that ppimv's affect this, mine works great.

Here's the deal, I have mine on teh 16 ohm tap, but I'm using a 100k resistor. What change would I experience if I drop to a 47k?

rockstah · Post by **rockstah** » Wed Dec 19, 2007 12:49 am

in theory more neg feedback. ( smoothing of the tone ) but using the PPIMV u probably wont hear any difference going from 100k to 27k especially if we are talking bedroom level.
get that PPIMV up to 3..4..5 and you will hear it. try it. its two solder joints.

Mark

ScottW · Post by **ScottW** » Wed Dec 19, 2007 12:50 am

charvel pointy head wrote:after the revelation that ppimv's affect this, mine works great.

Here's the deal, I have mine on teh 16 ohm tap, but I'm using a 100k resistor. What change would I experience if I drop to a 47k?

You'd get more negative feedback.

More nfb = tighter, smoother, tamer
Less nfb = rawer, more gain

rockstah · Post by **rockstah** » Wed Dec 19, 2007 3:33 am

but like i said you wont hear a difference until u get that PPIMV up loud.

ScottW · Post by **ScottW** » Wed Dec 19, 2007 9:18 am

rockstah wrote:but like i said you wont hear a difference until u get that PPIMV up loud.

+1

charvel pointy head · Post by **charvel pointy head** » Wed Dec 19, 2007 1:04 pm

now I'm torn. I like "raw" I like more "gain" I'm still a metal head at heart here. I think I will just try it and see if I like it?

HEAVIER THAN HELL · Post by **HEAVIER THAN HELL** » Wed Dec 19, 2007 2:24 pm

My fave has always been 68k on the 8ohm tap.

rockstah · Post by **rockstah** » Wed Dec 19, 2007 3:07 pm

HEAVIER THAN HELL · Post by **HEAVIER THAN HELL** » Wed Dec 19, 2007 6:00 pm

rockstah wrote:sigh

???

rockstah · Post by **rockstah** » Wed Dec 19, 2007 6:07 pm

hes not getting that yer not going to hear any effect with a different feedback resistor using a PPIMV unless that amp is loud. at 5 on the PPIMV u get 50% of your neg feedback circuit working the way it should. and thats if hes using a lin pot. with a log pot, what the master calls for, its more like 50% of circuit is back in effect with the volume at 7 or 8.

toner · Post by **toner** » Wed Dec 19, 2007 7:30 pm

charvel pointy head wrote:I like "raw" I like more "gain" I'm still a metal head at heart here.

Based on this, you should probably go for less negative feedback. Lowering the resistor value will give more NFB. Try your 100k on the 8 or 4 ohm taps.

As Mark mentioned, it won't make much difference until the MV is cranked up a ways.

curtg · Post by **curtg** » Thu Dec 20, 2007 11:23 am

toner wrote:Try your 100k on the 8 or 4 ohm taps.

As Mark mentioned, it won't make much difference until the MV is cranked up a ways.

+1

My 73 is 100k on the 4 ohm tap.

HEAVIER THAN HELL · Post by **HEAVIER THAN HELL** » Thu Dec 20, 2007 4:56 pm

rockstah wrote:hes not getting that yer not going to hear any effect with a different feedback resistor using a PPIMV unless that amp is loud. at 5 on the PPIMV u get 50% of your neg feedback circuit working the way it should. and thats if hes using a lin pot. with a log pot, what the master calls for, its more like 50% of circuit is back in effect with the volume at 7 or 8.

I was just stating a general preference as I don't use a post-PI master. I can see how it may have been taken wrong.

I'll have to try that post-PI mv with the 2M2 resistors, sounds interesting and your clips sounded great.

Metropoulos Forum

Got an nfb question now that I figured out mine works

Got an nfb question now that I figured out mine works

Re: Got an nfb question now that I figured out mine works