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previous: Randy Jamz I wouldn't do it, but you could fin... -- 9/2/2000 1:06 AM

Re: OT advise!

9/2/2000 10:03 AM
lion	Re: OT advise! Thanks Randy. In the meantime I did a little research, and came out with roughly the same figures: 4xEL34 = 1700-2200 ohms 4xEL84 = 3000-4000 ohms I've also been reading diff sources (R.G. - Randall Aiken - ect) trying to grasp the theory of OT's. As I understand it, the OT has no impedance per see, but a RATIO between the prim and the sec side - meaning that, what imp the tubes are looking into, depends on the load on the sec. So the figures for the 4xEL34 being around 2000 ohms, only holds true, as long as you have the correct load at the sec - say 8 ohms at the 8 ohms tap. If you double the load - 16 ohms on the 8 ohms tap, the tubes would actually be looking into 4000 ohms as the prim imp. So, by doubling the sec load on my OT, I would probably get a prim imp of 3400-4400 ohms, which should be OK for 4xEL84??? Someone please correct me if I'm wrong! Lion

9/2/2000 10:03 AM

lion

Re: OT advise!

Thanks Randy.

In the meantime I did a little research, and came out with roughly the same figures:

4xEL34 = 1700-2200 ohms
4xEL84 = 3000-4000 ohms

I've also been reading diff sources (R.G. - Randall Aiken - ect) trying to grasp the theory of OT's.

As I understand it, the OT has no impedance per see,
but a RATIO between the prim and the sec side - meaning that, what imp the tubes are looking into, depends on the load on the sec.

So the figures for the 4xEL34 being around 2000 ohms, only holds true, as long as you have the correct load at the sec - say 8 ohms at the 8 ohms tap.
If you double the load - 16 ohms on the 8 ohms tap, the tubes would actually be looking into 4000 ohms as the prim imp.

So, by doubling the sec load on my OT, I would probably get a prim imp of 3400-4400 ohms, which should be OK for 4xEL84???

Someone please correct me if I'm wrong!

Lion

Replies:

Randall Aiken Yes, it is true that a transformer ... -- 9/2/2000 6:20 PM