MV Tweaks Thread
Posted: Thu Dec 31, 2009 9:51 am
Just a thread on some tweaks I've found and am going to try as soon as I get my MV built. Nothing over the top; a lot of these be found on other parts of the site and can be applied to other amps as well as the MV, but I just wanted to compile my findings for what can be applied to the 2203 circuit. Feel free to share, add, discuss, etc.
.068uF capacitor on V2a (across 820Ω resistor) – gives mid gain boost
100kΩ resistor placed between PI input cap and MV wiper – reduces bass kill at low volume settings
Removing 1000pF bright cap on Preamp Gain – Can help alleviate brightness at low volume settings. Try other values to see what is desired.
100pF fizz cap – Can roll off high end. In some cases, it can be used more effectively with .1uF PI caps.
NFB resistor/speaker tap – By lowering the speaker tap (or doubling the resistor) you can get some different sounds. Lowering the speaker tap is usually more gainy and raw sounding, and vice versa with a higher tap.
Lower Filtering – Lowering the filtering, especially in the preamp (located under the board), will cut some of the low end punch for a looser sounding amp. It will also cause it to saturate more.
Resonance Control – 1Meg A pot placed between speaker tap and NFB resistor with a .0022 - .0047 capacitor placed between the middle and left terminal (ground).
And of course there’s the Lar/Mar and star grounding scheme to try out. More specifically with the Lar/Mar is converting your presence control into a cut control so it is effective at all volume levels. You can see a diagram of this here.
Happy New Year
Kramer
.068uF capacitor on V2a (across 820Ω resistor) – gives mid gain boost
100kΩ resistor placed between PI input cap and MV wiper – reduces bass kill at low volume settings
Removing 1000pF bright cap on Preamp Gain – Can help alleviate brightness at low volume settings. Try other values to see what is desired.
100pF fizz cap – Can roll off high end. In some cases, it can be used more effectively with .1uF PI caps.
NFB resistor/speaker tap – By lowering the speaker tap (or doubling the resistor) you can get some different sounds. Lowering the speaker tap is usually more gainy and raw sounding, and vice versa with a higher tap.
Lower Filtering – Lowering the filtering, especially in the preamp (located under the board), will cut some of the low end punch for a looser sounding amp. It will also cause it to saturate more.
Resonance Control – 1Meg A pot placed between speaker tap and NFB resistor with a .0022 - .0047 capacitor placed between the middle and left terminal (ground).
And of course there’s the Lar/Mar and star grounding scheme to try out. More specifically with the Lar/Mar is converting your presence control into a cut control so it is effective at all volume levels. You can see a diagram of this here.
Happy New Year
Kramer