Why vintage Marshalls have more balls

Everything from original vintage Marshalls to reissues.

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shakti
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Re: Why vintage Marshalls have more balls

Post by shakti » Sat Feb 18, 2017 2:09 am

Sounds good, but without a before and after comparison it's not really possible to say what it did. What are your impressions of the mod?
JTM45 RS OT, 1973 18W, JTM45/100, JTM50, JMP50 1986, JMP100 "West Coast", AC15, AC30, BF Super Reverb, Boogie Mk 1, Hiwatt CP103, DR103

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bill bokey
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Re: Why vintage Marshalls have more balls

Post by bill bokey » Sun Feb 19, 2017 7:29 am

RockinRocket wrote:That's is some great tone you got Bill!
Thanks ! :hairband:
RockinRocket wrote: Would the high measuring pots only make a difference in tone when turned up past the point of the mod?
Standard pots vs high measuring pots at maximum settings (high : slightly less bass)

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And now with all controls on 0 (high : more bass)

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So you can see the frequency response is always different, the entire curve is shifted to the left.



And if you also use a high measuring slope resistor (38k in this particular amp) :

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But the volume pot also has a slight effect on gain (red : 1M5, blue : 1M)


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RockinRocket wrote: 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
This one is not the most accurate. I'll let you know when I have some more accurate head cabs if you want ;)

shakti wrote:Sounds good, but without a before and after comparison it's not really possible to say what it did. What are your impressions of the mod?

Unfortunately I can't tell you any more. I played the amp for years before I modded the pots but I modded too many things at the same time (guitar strings, cabs and a few other tweaks in the amp)

For my next build I'll try and find the time to record a before/after clip ;)

awangotango
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Re: Why vintage Marshalls have more balls

Post by awangotango » Sat Oct 28, 2023 1:00 am

Q why old marshalls have more balz,
A two gain stages

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Re: Why vintage Marshalls have more balls

Post by bobtec » Wed Dec 27, 2023 3:05 pm

I think its what kind of caps and resistors you use Mark made some great sounding amps ****** makes good transformers Marshall got war surplus pparts the cheapest he could find Eddiesamp the OP transformer was changed.alot My SLP is now 30 yrs oldI lowered some caps So not as bright And the Pre amp as phase filter caps It is a great amp

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