tubes for these OPT?, pri 1.75Kohm, sec 2.5, 4, 8ohm, taps 20%, weight 4Kg

[heinrichs]

hey

i got 2 OPT for free some time ago with these specs:

pri 1.75Kohm,
sec 2.5, 4, 8ohm,
taps 20%,
weight 4Kg
no ideer about wattage.


and i have no ideer what to use them for... guessing it would have to be some parallel push pull? but i could really use some ideers, as to what tubes would make sence with these OPT.

I am open to any ideers, dont have to be the usual tubes.

-heinrichs

 

[danFrank]

Hi,
They should be large enough for PPP EL34 (4 of them). I do not know the quality of the transformers, but they would do well for guitar amp service. Do you play guitar?
1.75K Ohm is pretty low for a single pair of tubes.
Daniel

 

[smoking-amp]

8.8 Lbs, sounds like maybe a 70 to 100 Watt OT (for 20 Hz low end, would be more, maybe 120 Watts for 30 Hz low end). The low primary Z sounds like for parallel tubes. On the 20% taps, is this 20% of turns or 20% of impedance (.45 turns)? If 20% of turns, I think maybe EL84 has this 20% spec for UL mode. Could be made to work for a UL sweep tube too if the DC level could be dropped as well.

 

[nicoch58]

mismatch the secondary the load will be 3.5k ....

 

[hidnplayr]

I would use EL36 in triode, push-pull parallel (you could try in UL mode too, dont know how good it will work)
Should give over 30 watts, with those big OPT's you should have really nice bass I guess..