Why vintage Marshalls have more balls
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Re: Why vintage Marshalls have more balls
You're right actually, most modern parts such as resistors and pots that I've measured have mostly been slightly below value. Still within tolerance but below. I ordered a 5K Pot recently from someone on Ebay and I asked if they could measure the pot for me to make sure its 5K or over. They said they couldn't believe how much they varied!
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Re: Why vintage Marshalls have more balls
Btw, it's pretty easy to open up potentiometers and shave off some of the carbon and increase the value. A little hard to do with alphas because the carbon track does not protrude out like cts pots and its very thin and easy to scrape off, but still works. A little goes a long way and a sharp razor blade will smoothly shave off what you need. Great for dialing exact circuits, ala Howard dumble.
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Re: Why vintage Marshalls have more balls
Ah, you can open up Alphas can you? I heard you couldn't get to the track because they're clamped together.
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Re: Why vintage Marshalls have more balls
Just tried it, hard not impossible. Pot was 1M nowis 1M4.
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Re: Why vintage Marshalls have more balls
Cool! Do you just scratch the outside of the carbon track with a knife?
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Re: Why vintage Marshalls have more balls
Razor blade, yeh. Just be careful, the carbon trace is very thin
way too easy to slice the track in half

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- neikeel
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Re: Why vintage Marshalls have more balls
Any chance to try in the amp yetwhopperplate wrote:Razor blade, yeh. Just be careful, the carbon trace is very thinway too easy to slice the track in half

Neil
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Re: Why vintage Marshalls have more balls
I know
I assume because I can get a reading it will work, but I will have to test of course, haven't yet. Thanks for forced disclaimer 
I intend to do this to the alpha pots in my 100watt clone, so I will report how successful I am at the time.



I intend to do this to the alpha pots in my 100watt clone, so I will report how successful I am at the time.
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Re: Why vintage Marshalls have more balls
Report back when you do. Be interesting to see how well it does work! I've heard of people doing it but never tried it. I'm assuming you'd have to try and evening cut off enough all the way around to keep the taper the same?
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Re: Why vintage Marshalls have more balls
That's what I have assumed concerning retaining the original taper; no matter the brand of potentiometer I try to evenly scrape the entire surface for this matter.
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Re: Why vintage Marshalls have more balls
If you scrape the entire surface, try your fingernail first
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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Super 100 amps: 1202-119 & 1202-84
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Re: Why vintage Marshalls have more balls
Any updates on this? I am curious to hear if anyone has success modding Alpha pots and what their findings are with regards to tone/EQ.
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Re: Why vintage Marshalls have more balls
Unexpected move took place, lost my rehearsal space for testing
working on finding somewhere to turn up. Has put a hold on all sonic experimentation, but it's sooo all on my mind and in my intention to document asap




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- bill bokey
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Re: Why vintage Marshalls have more balls
I just modded the pots on my SL68 clone. The volume & bass 1M (were slightly below 1M) are now between 1M4 and 1M5, the 250K is now 310K, the 25K around 30K . I can't remember the exact value but it was the same as my '67 Super Bass.shakti wrote:Any updates on this? I am curious to hear if anyone has success modding Alpha pots and what their findings are with regards to tone/EQ.
Here's a clip :
https://soundcloud.com/castle-made-of-s ... 68-replica
(I obviously didn't think of recording a before clip !

And here are a few pics of this build :










Oh and I used Pyramid Monel strings, great stuff !
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Re: Why vintage Marshalls have more balls
That's is some great tone you got Bill!
Would the high measuring pots only make a difference in tone when turned up past the point of the mod?
Who made the head cab? Its surprisingly hard finding someone who builds with all genuine Marshall parts whith the correct cab construction, roundover, wood thickness, back panel ect
Would the high measuring pots only make a difference in tone when turned up past the point of the mod?
Who made the head cab? Its surprisingly hard finding someone who builds with all genuine Marshall parts whith the correct cab construction, roundover, wood thickness, back panel ect