#6411
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Thanks Pete, I found them on eBay.
The seller is GDaudio. |
#6412
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Wow, those are sweet! They are generating quite a few lumens! LOL
Pete |
#6413
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Quote:
They need to be run at 30ma or below to work properly. [IMG][/IMG] |
#6414
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The Sylvania 7n7 has caused me to go through another round of tube rolling. Now using the new Tungsol 7581a tubes along with a EH 5u4. Wonder if I could use the 5ar4 instead, the 7581a can take more voltage than a 6l6c.
Also have a technical question. Dennis says the KT88 Firebottle amp has a regulated screen supply. How is it being regulated? It's obviously not a tube regulated system so I assume there is a solid state device being used?I didn't notice any of them in the picture in the manual though it could be hidden I suppose. |
#6415
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Hey Isaacc7, Dennis regulates the output tube screen grids (in Pentode configuration) and the input tube plate voltage with zener diodes.
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#6416
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Good to know, thanks. Do you have any opinion on using the 7581a with the 5ar4? Also the manual says that you can use a 6bx7 as the input, what about the 6bl7? The preamp I'm getting has pretty high gain so I might have to move to the 6bx7 and would be interested it expanding my options to the 6bl7 if I could.
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#6417
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Also curious if anyone has ever used a 7fa7 in the input of the KT88 firebottle. Like I said, I'll probably need to use a lower gain tube than the 6sn7 and while the 6bx7 is the lowest the 7af7 seems like it would be a useful alternative.
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#6418
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The only tubes other than a 6SN7 which I've used in my Firebottle SE KT88 HO were 6SL7 and 6BX7. Didn't like either one of them as, to my ears, they made my amp sound more shrill. Lots of high frequency energy and detail but too much so, less so with the 6BX7.
Last edited by Bombadil; 05-11-2021 at 11:02 PM. |
#6419
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I’ve noticed some bad tube combos that resulted in shrillness. While the GE 6sn7 with KT88 tubes had an open, super clear sound, the 7n7 with Kt88 (and kt66) had too much high frequency energy. The 7n7 and the 7581a on the other hand is an amazing combo. It’s “thicker” but the bass and lushness are intoxicating. I fully anticipate messing with output tubes again when I try the 6bx7.
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#6420
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I’m interested in an Inspire amplifier but keep getting beaten to the punch in buying one on either AudioMart or eBay.
I’ve noticed that prices on eBay straight from the maker have recently just about doubled from what they were a few months ago now that the units have a volume knob and don’t require a preamp. Can anyone speak to why the prices have climbed so much? |
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