How to tweak gain in any vintage amp. We hot rod our 62 Princeton with some added gain.

Someone asked about techniques for increasing pre-amp gain in an amp. Here's how simple it is. Ask your questions in the comments & subscribe for more videos. universal gain stage

[@Finom1]

Thank you for the Line Drawing, I am a visual leaner. Fantastic!!!

[@roncarter2188]

This was one easiest understood ways that I have seen to tweak the sound and gain, thanks so much for the info. I'd love to see more of your videos on the mods and tweaks to amps, great job.

[@giulioluzzardi7632]

Thank's exactly what we needed to know explained in a manner that can be understood , more please on tone section too.

[@Finom1]

Hi Pat, thank you for sharing your wisdom with us!!!

[@docdeens4030]

Damn this made more sense than nearly any other explanation I've heard. Thanks!

[@toddmayer6859]

Thank you Pat! Somehow the lightbulb finally went on over my head. I understand how to bias a tube now ....

[@robertbarcus2008]

Thanks for all the info and your knowledge in time we really appreciate it

[@johnmarshall3903]

I really like how you explain things, thank you!

[@patfurlan]

Glad it was helpful!

[@clownhands]

I design guitar amplifiers. About half of what this guy said is correct.

[@DavidBrown-ez5jc]

Hey bud excellent explanation on the va le tweeks loving this

[@johnb4024]

Do any of these modifications have an impact on the power tube bias? If I was to put in a modification with different resistors for a cold clipper selector, would I have to re-bias the amplifier?

[@Finom1]

Pat, could you please explain, Grid Stop Resistors How and Why you would need to use them. Thank you for the drawings!!!

[@patfurlan]

Finom1 grid stops are used to reduce noise by blocking stray signals from activating the grid

[@Finom1]

How would you us this - www.ampbooks.com/mobile/amplifier-calculators/grid-stopper/calculator/

[@markgrimm3564]

what cathode restorer value are you using

[@Turboy65]

Changing the cathode resistor does not change gain, it does change the operating point instead. Using a higher value, such as 10K, turns the stage into a cold clipper like the overdrive stage of a master volume Marshall 2203 or 2204. Changing that plate resistor to 330K will let you get into heavy metal territory.

[@jonbuckner4467]

Thanks x 100

[@robertbarcus2008]

Can you keep doing that at each stage at V1 and V2 for instance and add more gain adding a 220 resistor to the plate instead of the hundred k

[@patfurlan]

robert barcus yes each stage works in a similar manner. The ART is in not overdoing it... and ending up with a mess. Sonically speaking ...too much salt can ruin the soup.

[@Finom1]

What make & type of caps do you like most for the signal path for each location?

[@patfurlan]

always Tubular ...they sound better

[@Earlvis]

So the Mallory 150’s

[@mikecamps7226]

I would suggest a bit of a remodeling of the amplifier as its very close to a single channel tweed deluxe. I would make the PI dedicated with the first stage gain as is with the tweed deluxe cathodyne PI (it presently is a cathodyne but not complete), and move the trem circuit to the first preamp tube 2nd half......then switch it to cathode biased power tubes rather than the fixed bias and alter the trem for the cathode bias operation. Next step would be to change the 5y3 rectifier to a 5U4 or a GZ34 to bring up the power tube plate voltage and readjusting the down stream plate voltages properly...….but doing so will make the output transformer marginal, so I would change that to a 60's/70's deluxe output transformer so it can handle the wattage. It would transform into one screaming amp for a small amp...… oh I forgot......eliminate the feedback resistor too As best as I can tell this is a 1960 or 61 6G2 series amplifier.....single tone control, so it has minimal signal loss.....2 6V6's in class AB push pull

[@deeem-tee799]

Your lecture added nothing to the matter at hand ….thank for the “input”?

[@michel333100]

Hi Pat, what value is your bypass cap that you change? Thanks

[@patfurlan]

I like 8mfd and 10mfd ... traditional values are 25mfd for fenders and .68 for Marshalls... the smaller the value the less gain and the more treble content ...

[@PurposefulPorpoise]

So if i was gonna add a 12ax7 in between the 2 preamp tubes, would you just copy/paste the first gain stage? Or would u want the second stage to “compliment” stage 1, by maybe boosting highs and cutting lows/mids? Thank you for the vid!

[@patfurlan]

Yes pretty much copy and paste, but you shouldn’t need an extra gain stage if you unlock all the hidden gain in your existing setup

[@moforockband]

Hi Pat, I have a '77 Traynor YRM-1 that I wish to smooth the pre-amp overdrive on. It sounds a little nasty when in overdrive (ie when preamp volume on 10). It has a cold clipper gain stage with 85 volts on the 3rd stage. For the meantime I have increased this voltage to 160 to get more cleans, and use a dirt pedal for gigging. Any suggestions for us YRM-1 owners??

[@Finom1]

Hi Pat, is the grid stop resistor only used on the first preamp tube? Thank you.

[@patfurlan]

Finom1 they can be used on any tube input. You see them on power tubes. I add one to the tremolo tube if you hear ticking on some amps. They are very useful.