Change my 8417's Quicksilvers to this?

Original Burnedfingers · 11th January 2006, 12:37 AM

A few years back I owned a pair of Quicksilver KT88's in addition to my sets of 8417's. I took the back off and made this schematic that I will try to post. Unfortunately I sold the KT88's but I rather liked the sound of them. It was pleasing. I am thinking of redoing a pair of my 8417's to this circuit and would like your input.

Thanks,
Joe

Original Burnedfingers · 11th January 2006, 12:40 AM

I will post the 8417 schematic also

Original Burnedfingers · 11th January 2006, 11:25 AM

Any thoughts or comments would be appreciated. Unfortunately I will be out of town until friday without web access.

Front end tubes are 12AX7 and 12Bh7 for both amps.

Giaime · 11th January 2006, 11:31 AM

Pretty basic amps, I don't know the 8417 tube (similar to 6550?) but I do like KT88s.

Please note that negative feedback resistor and capacitor should be tweaked according to your specific output transformer.

Original Burnedfingers · 11th January 2006, 11:36 AM

Giaime

The output transformers are the same except the KT88's didn't have a 16 ohm speaker tap. They are both 4300 ohm impedance.

The 8417 is a great sounding tube and right now my 8417's will work with 6550's,KT88's or 8417's with just a rebias. They are rock solid with any 8417 I thow into them. They are just costly to purchase since they aren't made anymore.

Original Burnedfingers · 12th January 2006, 09:47 PM

Anyone?

Original Burnedfingers · 12th January 2006, 09:49 PM

This may very well be the longest thread where I am the only one posting.

poobah · 12th January 2006, 09:59 PM

Maybe you should restate your question... It's not real clear, at least to me, what you are asking.

anatech · 12th January 2006, 10:04 PM

Hi poobah,
Joe is asking what you think about changing his 8417 amp into a KT-88 type amp.

Will you need more drive for the outputs?

-Chris

poobah · 12th January 2006, 10:13 PM

Well,

The Leslie speaker amp I am rebuilding has 6550's (almost KT88) ... so yeah, I like them. They growl like hell. Oddly though, many of the best hifi designs (from reading ALONE) used 6550's.

With the SE craze in full swing right now... noone seems to be talking much about PP.

I do know, again from reading, that the new "tung sol" 6550 is getting pretty goods reviews... in terms of all that stuff we make fun of though!

I am getting the itch, real bad, to build an hifi tube amp...

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11th January 2006, 11:25 AM	#3
Original Burnedfingers diyAudio Member Join Date: Nov 2002	Any thoughts or comments would be appreciated. Unfortunately I will be out of town until friday without web access. Front end tubes are 12AX7 and 12Bh7 for both amps.

11th January 2006, 11:31 AM	#4
Giaime diyAudio Member Join Date: Oct 2004	Pretty basic amps, I don't know the 8417 tube (similar to 6550?) but I do like KT88s. Please note that negative feedback resistor and capacitor should be tweaked according to your specific output transformer.

11th January 2006, 11:36 AM	#5
Original Burnedfingers diyAudio Member Join Date: Nov 2002	Giaime The output transformers are the same except the KT88's didn't have a 16 ohm speaker tap. They are both 4300 ohm impedance. The 8417 is a great sounding tube and right now my 8417's will work with 6550's,KT88's or 8417's with just a rebias. They are rock solid with any 8417 I thow into them. They are just costly to purchase since they aren't made anymore.

12th January 2006, 09:47 PM	#6
Original Burnedfingers diyAudio Member Join Date: Nov 2002	Anyone?

12th January 2006, 09:49 PM	#7
Original Burnedfingers diyAudio Member Join Date: Nov 2002	This may very well be the longest thread where I am the only one posting.

12th January 2006, 09:59 PM	#8
poobah diyAudio Member Join Date: Nov 2005	Maybe you should restate your question... It's not real clear, at least to me, what you are asking.

12th January 2006, 10:04 PM	#9
anatech diyAudio Moderator Join Date: Jun 2004 Location: Georgetown, On	Hi poobah, Joe is asking what you think about changing his 8417 amp into a KT-88 type amp. Will you need more drive for the outputs? -Chris

12th January 2006, 10:13 PM	#10
poobah diyAudio Member Join Date: Nov 2005	Well, The Leslie speaker amp I am rebuilding has 6550's (almost KT88) ... so yeah, I like them. They growl like hell. Oddly though, many of the best hifi designs (from reading ALONE) used 6550's. With the SE craze in full swing right now... noone seems to be talking much about PP. I do know, again from reading, that the new "tung sol" 6550 is getting pretty goods reviews... in terms of all that stuff we make fun of though! I am getting the itch, real bad, to build an hifi tube amp...

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