What OT for a Pair of KT88's?

[eddie25]

I think you need more like a 4500-5000 Ohm primary.
http://www.tubezone.net/pdf/kt88new.pdf

Hammond 1650R?
http://www.tubesandmore.com/scripts/fox ... m=P-T1650R

I've never seen a secondary done like that. I'm assuming you can get 4/8/16 out of it somehow though.

[Hellhammer]

I've never seen a secondary done like that. I'm assuming you can get 4/8/16 out of it somehow though.

http://www.hammondmfg.com/1608.htm
Scroll down. They now also have an easy wire secondary series!
http://www.hammondmfg.com/1608A.htm

[eddie25]

So you only get one choice for a secondary impedance with that one? Am I missing something?

[Alexo]

So you only get one choice for a secondary impedance with that one? Am I missing something?

You can have 4/8/16, it just requires more complex switching, I think it takes a 3 or 4 pole switch, and they have hookup instructions on their site and their packaging. It is a PITA, but the 1600 series transformers are sort of incredible, and their secondary wiring technique plays a role in their performance.

[eddie25]

Aha. Well I was just about to bitch about this, so thanks for clearing that up. The 60 watt version is exactly what I need if I can get switchable impedance.

Still kinda sucks the 'new improved' versions are like 20% more money. Do they really cost that much more to make I wonder?

[super100]

Aha. Well I was just about to bitch about this, so thanks for clearing that up. The 60 watt version is exactly what I need if I can get switchable impedance.

This should help.

https://secure.cedist.com/scripts/foxwe ... em=P-H1600

http://www.tubesandmore.com/scripts/fox ... em=P-H1600

http://www.tubesandmore.com/scripts/fox ... tem=P-H394

[eddie25]

I saw that, but does anyone have a diagram for how it's wired so I could save $12? I could probably think it through, but I would need to the switch in front of me. There must be a way to do it with two switches also.

[ToneMerc]

Aha. Well I was just about to bitch about this, so thanks for clearing that up. The 60 watt version is exactly what I need if I can get switchable impedance.

This should help.


http://www.tubesandmore.com/scripts/fox ... tem=P-H394

FYI, they don't send you the wiring diagram with the switch.

[Alexo]

I ordered that switch once, pretty much a waste of money. Love CE/Tubesandmore, but gotta say, any one of us could just wire up a rotary switch like that in 5 minutes.

[ToneMerc]

I ordered that switch once, pretty much a waste of money.

Same here

[eddie25]

Well, it was easy to figure out with two switches, if I'm not mistaken. A DPDT and a SPDT, both ON-NONE-ON. It gives you four options obviously. Now I just wonder, what is the impedance setting, when it is like the 16 ohm hookup, but with the yellow wire going to the jack, instead of grn/yel? Sorry to hijack the thread.

[David Root]

fusionbear, Edcor CXPP70-MS-3.5K, has 4/8/16 secondary too, without all the old fashioned Hammond wiring stuff. www.edcorusa.com

Edcor stuff is very good!

[fusionbear]

fusionbear, Edcor CXPP70-MS-3.5K, has 4/8/16 secondary too, without all the old fashioned Hammond wiring stuff. www.edcorusa.com

Edcor stuff is very good!

Thank You!