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View Full Version : Nearly new JJ KT88 Matched Quad for sale.


JohnJo
16-09-2016, 19:50
Matched quad of JJ KT88 for sale.

Bought these new two weeks ago from Hotrox but you know how it goes, preferred something else.

They have about 10 hrs on them.

Cost me £120, how does £85 delivered sound?

http://i1229.photobucket.com/albums/ee462/castle48/JJ%20KT88/D84EE95F-24FF-49D4-BEEB-AFAF68203E9C.jpg (http://s1229.photobucket.com/user/castle48/media/JJ%20KT88/D84EE95F-24FF-49D4-BEEB-AFAF68203E9C.jpg.html)
http://i1229.photobucket.com/albums/ee462/castle48/JJ%20KT88/AEBF5A5C-150A-480D-A50E-5AAE31E2E943.jpg (http://s1229.photobucket.com/user/castle48/media/JJ%20KT88/AEBF5A5C-150A-480D-A50E-5AAE31E2E943.jpg.html)
http://i1229.photobucket.com/albums/ee462/castle48/JJ%20KT88/E6B2FBDD-D4BE-4448-908F-221C16A0CD93.jpg (http://s1229.photobucket.com/user/castle48/media/JJ%20KT88/E6B2FBDD-D4BE-4448-908F-221C16A0CD93.jpg.html)
http://i1229.photobucket.com/albums/ee462/castle48/JJ%20KT88/D5010958-2F48-4940-9EB8-61683CF4DD89.jpg (http://s1229.photobucket.com/user/castle48/media/JJ%20KT88/D5010958-2F48-4940-9EB8-61683CF4DD89.jpg.html)
JohnJo
22-09-2016, 19:47
Bump
JohnJo
12-11-2016, 17:02
Bumparoo
JohnJo
22-11-2016, 12:39
bump
Lawrence001
22-11-2016, 14:08
I'll sound stupid, but can KT88s be put in any KT66 amp for more headroom? Or are the currents and voltages different and I'll blow it up? Is there an easy way for a sensible layman to measure if it can take them?
JohnJo
22-11-2016, 19:15
I'll sound stupid, but can KT88s be put in any KT66 amp for more headroom? Or are the currents and voltages different and I'll blow it up? Is there an easy way for a sensible layman to measure if it can take them?

I doubt if they're a direct swap, even with a bias adjustment. The heater current is a good 25% higher for a start which is going to put That supply under pressure.

I imagine it's a similar story with the HV supply too it don't know enough to make an informed reply. I would guess that although the KT88 can withstand higher voltages, it probably needs a higher voltage than the KT66 to operate in its sweet spot.

That's assuming the pin-out is the same.
https://frank.pocnet.net/sheets/086/k/KT66.pdfhttps://frank.pocnet.net/sheets/164/k/KT88spec.pdf
JohnJo
30-11-2016, 22:03
Will swap for a good matched quad of Mullard reissue el34s, Primaluna EL34 or similar.
JohnJo
26-01-2017, 10:12
Sold!!