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previous: Mark Abbott Dear Joe ... -- 10/2/2000 8:45 AM View Thread

Re: Questions for Speedracer.

10/3/2000 3:03 AM
Re: Questions for Speedracer.
Hi Mark:  
Stephen's address is:  
If I may, I would add that he does beautiful work.. He's really a craftsperson in the classic sense.  
Also I've seen quite a few posts about JTM 45 amps, and I thought you said in a reply that the output transformer of these amps has a 8K primary impedience, is this true?  
To the best of my knowledge, yes it is. I have a couple original OT's (RS Spares Deluxe) and have read up on newgroups etc.. the consensus seems to be 8K, and at first I was sceptical. But running listening tests at 6.6k as well as 8k there is no mistaking the correct primary load IMHO. 6.6k is nice, but a little buzzy and not quite right. 8k is just flat out unreal.. Also, the older of the 100W OT's we RI'd was 4K, which would be fatally high with EL34's (esp at >500Vg2!) .. it may be circumstantial evidence, but it makes sense to go with half of your 50W load.. The final answer is that I have not peeked under the hood of a real JTM45 to see. My $5 is on 8K though. ;)  
Joe Pampel

Ian Anderson Joe/Speed,Any news ... -- 10/4/2000 12:20 AM