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Old 17th May 2012, 02:01 PM   #11
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Not sure you would be carrying it to a bbq would be an option without a tow motor. That would be alot of iron!
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Old 17th May 2012, 03:17 PM   #12
Cassiel is offline Cassiel  Libya
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Yes, I don't think he's aware of the trouble ahead.

Quote:
Doing it as big as we can, just because we can
Can you? We'll see.
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Old 17th May 2012, 04:49 PM   #13
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"there's no real reason for so much power, just want to do it because its uncommon"

It is uncommon because it is impractical, costly, and will be severely compromised in sound quality. If you really want to have a lot of power and great sound why not build a PP 845/211/GM70 amp. The first time you melt a meter probe on 1000V will give you a real thrill too.
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Old 17th May 2012, 06:42 PM   #14
data is offline data  Australia
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I really don't see why you guys have such an issue with this, given he has hungry speakers!

You need headroom for transients.
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Old 18th May 2012, 12:14 AM   #15
chrish is offline chrish  Australia
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I think the issue is he wants to do something 'different' that is not normally done, without realising that there is normally a good reason for it not being done. On top of that, he wants someone else to provide all the answers so he can have a unique amp.

Also, the design process is all *** backwards. 'I want 8 KT88 in triode and use these regulators I have already purchased, I want it to be unique and I want you to design it for me' is going to end in tears. Perhaps a statement of 'I like this KT88 SE amp I have, but I want to drive these 87dB speakers' is a better design starting point. Others will probably had a similar design goal and you will be able to look to their solutions for a suitable design.

In short - doing something different is great if you have the skills and resources to do it yourself. If you don't, and you want a solution presented on a platter - then look to a tried and tested design.

Cheers,

Chris
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Old 18th May 2012, 12:43 AM   #16
yoaudio is offline yoaudio  United States
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Here's your 8- KT88 amp kit-

Click the image to open in full size.

Build a pair of M-125 Mono-blocks from Bob Latino.
125 watts from 17 Hz to 32 KHz at less than 1% THD in ultralinear - 65 watts in triode.

Last edited by yoaudio; 18th May 2012 at 12:45 AM.
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Old 18th May 2012, 12:55 AM   #17
BHD is offline BHD  United States
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Eight per side, why not twelve?

Here you go, and good luck.

schem-input-driver300wjan06
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Old 18th May 2012, 07:28 AM   #18
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Quote:
Originally Posted by regiregi22 View Post
Yeah, I know it is a very different beast (From what I've read. I haven't heard any PP yet), but I wanted to keep it as close as possible regarding:
-Triode mode
-Class A1 operation
-No feedback
-Conservative rating: Many tubes means same power, but long life for them.

I like your idea of more tubes in a SE setup, I didn't know it was possible to use more than 1 tube in SE to have more power. As it seems, I am a totally newbie in the tube world. Still much to read and learn, on the way
Nope, not close enough. If you like SE, it has to be SE. How about 4XGU50 triode per side? (35 watts per channel more or less)
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Old 18th May 2012, 08:16 AM   #19
AJT is offline AJT  Philippines
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i've done 8 KT88 trioded per channel: this baby eats 450watts idling:
Quote:
-Triode mode
-Class A1 operation
-No feedback
-Conservative rating: Many tubes means same power, but long life for them.
Click the image to open in full size.
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Old 18th May 2012, 09:37 AM   #20
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Quote:
Originally Posted by Cassiel View Post
Yes, I don't think he's aware of the trouble ahead.

Can you? We'll see.
Then we should change "Doing" by "Trying"? Trying, just because we can.

In fact, I though I was asking for someting quite common. 4x tubes per channel in triode mode? I am a tube noob, but, is this REALLY a so strange thing? I am not needed for 1k watts, but something in the 30W-80W ballpark. Something that can stand up against a plain gainclone powerwise, nothing more.
I may admit I thought it was a bit exaggerated to think of 8x tubes per channel, or even arrogant. Now I am sure. Excuse my ignorance.


Quote:
Originally Posted by chrish View Post
I think the issue is he wants to do something 'different' that is not normally done, without realising that there is normally a good reason for it not being done. On top of that, he wants someone else to provide all the answers so he can have a unique amp.
Chris
In fact, I though that a 4 tubes amp operating in triode wasn't a so "unique" thing, that's why I was asking for proved and tried designs, in order to compare them and learn how do they work. Why do values change between similar end designs. Why and how are things done in each case.


Quote:
Originally Posted by chrish View Post
In short - doing something different is great if you have the skills and resources to do it yourself. If you don't, and you want a solution presented on a platter - then look to a tried and tested design.

Cheers,

Chris
As I said.... that's really what I was asking for. I know that my end build will be unique in the sense that this is DIY and no two designs are exatly the same. But having some directions on already proved designs can give me some ideas on how to combine them.

Every project I have ever started never ended as the idea it started to be, so these are just my thoughts, not a final fixed idea. If it were, I were not asking for advice.


Thanks yoaudio for your valuable opinion, that's what I was asking for. My last one project was in the kit form, this time I would like to source components by myself. But that's the point of desing I was looking for.

Tony, I really like your project. A separate PSU when going so big is an interesting approach. I would have gone with a closed enclosure. Coming from the SS world, one thing surprises me is the common tube builders approach of placing components outside the case. I can understand it's done for valves for heat reasons, but seems to me that its too far common to place other unnecesary (and dangerous!) components outside the enclosure. For example, in your desing, I would have gone with the PSU in a closed case. That way it seems less obscene, fragile, and the tube module can be piled on top of it. But that's just my side of view
Great and impressive design all in all!


Thank you very much guys for your advices. They help my feet to keep on the floor.
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