I too go for 56s but have not found a pair of balloons which were listenable due to noise. Manuf. not important. I run a tall bottle Westinghouse 6sn7 with the copper posts and any 80 will due.

Does anyone have a list of the different types of output tubes that can be used with the Inspire KT150 Hot Rod amp?


I recall a hand-written list Dennis took a photo of and someone posted it here or another forum. Cannot find it.
There are some old 2013 posts that talk bout different tubes but I thought Dennis handwritten list was more extensive.
Reached out to Dennis too, to see what he can provide, and maybe it's in the gallery here or something, cannot find it.

Hey decooney, if yours is one of the new Triode-strapped KT-150 Hot Rods then asking Dennis for output numbers would be best.
straitwire

Think I might have just found it. Saved a copy. I forgot, some times he adds this as a photo to the sale ads.



https://lh3.googleusercontent.com/A8...A=w968-h726-no

I believe this list is for Pentode configuration, looking at the bias resistor value and the power levels.

Thanks so much for the list. In my PSE, I’ve always just stuck to either KT88’s or 6550’s.

Okay, maybe you can help answer a few questions. This is the tube list Dennis offers with the Inspire Fire Bottle KT150 Triode Hot Rod sale ad, one of the last pages on the auction. This is where I re-found the photo. I have a note out to Dennis, he may see it next week.

My amp has "Triode" listed on the face, and runs KT150s, and many of these same tubes,

...so does that make it a pentode or triode configuration? And, will some these tubes not work on my KT150 Triode Hot Rod amp?

Hey decooney, your amp is configured in the latest Triode strapped circuit, I went to eBay and pulled down the old/sold listing for your amp and there isn't a picture of a tube list for that amp, but there may be a list by now. With what I know about the circuit I can say that you can run KT-150-120-90-88, and 6550's,...all the big tubes, the KT-77-66, and 6L6-6CA7/E34L and the 6V6 I don't know for sure but probably, the 6V6 might red plate though. Dennis will get back to you as soon as possible, thanks for your patience...straitwire

UPDATE:
Okay, may have a answer. Dennis got back to me and clarified why I'm having trouble finding the correct tube list for my recent amp purchase of the Inspire KT150 Hot Rod amp":

"Sorry for the confusion …. I have not done a tube chart for the Triode Hot-Rod version. I will gather up a bunch of tubes next week and make a chart for the “Hot-Rod” version. The chart you may have seen was for the triode SET “Fire-Bottle”. This is the lower powered version of your amp. Talk to you next week."

I let Dennis know I would post it here once he creates it for others who may want it too. I thought my amp was 10wpc. Then I see HO again on the front.
So now I'm even more curious, what is the power of my "HO" Hot Rod amp then with two KT150s in it?

https://lh3.googleusercontent.com/AJ...=w1218-h913-no

This forum seems kind of "dormant", so I'll step in with some observations on my current system (rig is on my signature):

1. Even though I have yet to get me a larger Subwoofer (Rythmic LS-12), the sound in my system has tangibly gone to a higher level through modest source modifications (Schiit EITR and JPlay SW). Now I'm not even sure I need that sucker :)

2. The above additions have made me reconsider the KT-77´s (definitely my favorites up until now) for the KT-88's (all Genalex, of course), just because the neatness of JPlay through a virtual network using Linn Kazoo and MinimServer through JPlay makes the sound so much detailed and transparent sometimes I miss some more body (not that it is required, but it is just my preference).

3. The combination of the KT-88's with the new sourcing components (other things being equal) is fantastic! Similarly, I can use the KT-77's with JPlay Mini instead of the cited virtual network and get roughly the same results. At this point I'm not sure what I like best, I guess it depends on the recording quality of each music selection.

I've always been a nut for transparency and detail, along with musicality and body of sound. I'm getting there so fast I cannot believe it! For the first time in years I feel I'm sitting on the platform which will witness my last audio days ... Dennis Had Inspire Pre's and Amp's (in Triode) rule! I'd like to urge you to chase your sound objectives through converging gradual mods and improvements until you really feel you are close enough to that envisioned Holy Grail and can finally relax and harvest the results of your efforts. It is worth it!