OT windings question

[hebaton]

I have a JTM45 clone built by Trinity. Everyting seems up to original spec on the board but the amp sounds quite different from a previous clone I had.
I know the OT they used has 6K and 8K primarys. ( not sur which they used )
What was the original JTM45 Ot primaty and, would the fact that : " Trinity has the same turns ratio but is wound in a different pattern to accommodate extra taps " make that amp sound significatly different ?

THanks !

[bepone]

steel core laminations have big influence on sound, also if the winding is the same.. so 2 transformers cannot be the same if the winding is the same and laminations are not the same type.. then you change also winding type... you can have big difference

[hebaton]

What sould be theplate voltageon the Ktt6 in a JTM45 clone ?

[martin manning]

There is an old hand-drawn schematic that shows 440 VDC.

[R.G.]

" [...] but is wound in a different pattern to accommodate extra taps"

Winding pattern is huge. It's an even bigger contributor to frequency response than laminations and primary inductances.

And that is assuming that nothing, not a single component connection or tolerance add-up is different.

[martin manning]

I know the OT they used has 6K and 8K primarys. ( not sur which they used )
What was the original JTM45 Ot primaty and, would the fact that : " Trinity has the same turns ratio but is wound in a different pattern to accommodate extra taps " make that amp sound significatly different ?

My understanding is that JTM45 originally had 8k primary (which is too high), and then went to 6k6.

[pdf64]

I know the OT they used has 6K and 8K primarys. ( not sur which they used )
What was the original JTM45 Ot primaty and, would the fact that : " Trinity has the same turns ratio but is wound in a different pattern to accommodate extra taps " make that amp sound significatly different ?

My understanding is that JTM45 originally had 8k primary (which is too high), and then went to 6k6.

I think it was the other way around, the first year or 2’s production used the RS DeLuxe wired for 6k6 primary and 15 ohm secondary, then went to Drake 784-103, which was just under 8k primary, 8 and 16ohm secondary.

Marshall database -
http://marstran.com/Historic%20Data%20Base.htm

Original schematic with voltage chart https://el34world.com/charts/Schematics ... ad_45w.pdf

Bear in mind JTM45 was a range, with guitar, bass, organ and PA models, all with different tone shaping
https://el34world.com/charts/Schematics ... pa_45w.pdf
http://raw-sewage.net/images/jtm45.jpg

[hebaton]

THanks Everyone,
That's the info I needed.