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Re: Marshall JTM45/100 questions

11/21/2005 1:03 PM
Re: Marshall JTM45/100 questions
Having built for Diaz last year, specifically Warren Haynes special, which uses (2) 100 watt OT`s!!, had no schematic to follow, I just paralleled the pri/sec, BUT, didn`t run ANY feedback, it would just howl, the TONE, Warren` still uses TWO of those ampsI built him!!  
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11/21/2005 5:19 PM
Dave H

"It does seem that one should be able to parallel everything"
You can but transformers in parallel are not like resistors in parallel. If you parallel two 50W output transformers (both primary and secondary) the impedance doesnít change as the turns ratio hasnít changed. If the transformers each had a primary impedance of say 4k for two 6L6/EL34 then two of them in parallel will still have a primary impedance of 4k. It will work but itís probably not what youíd want for four output tubes.  
11/22/2005 11:10 AM
Ace Pepper

Thanx for all the tips/suggestions! Someone @PlexiPalace suggested that I connect an 8ohm load/speaker to the 16ohm taps. Assuming 8k primaries (on the two 50w OTs) that's supposed to reflect 4k to the tubes, which would be about right for a 100 watter, no? I know whatcha mean Dave, that does seem kinda high. Too high to get 100w of output? 100w OTs are usually around 2k or so. Hmmmm... One person said he'd done an amp this way (2-OTs paralell) and it works, soooo... I guess I'll give it a try when I get a chance.  
Thanx for the input!!

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