Cheap 4Wpc valve

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IslandPink
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#1 Cheap 4Wpc valve

Post by IslandPink »

Another interesting one from Thomas Mayer :

http://vinylsavor.blogspot.co.uk/2014/1 ... -6ge5.html

6GE5 : get your 12-pin sockets out !
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Alex Kitic
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#2 Re: Cheap 4Wpc valve

Post by Alex Kitic »

IslandPink wrote:Another interesting one from Thomas Mayer :

6GE5 : get your 12-pin sockets out !
As usual, a beam tetrode used as triode.
It seems that for some people tube evolution stopped with triodes... or is it that their knowledge and expertise stopped there?
I must say I am bored with "incredibly linear triode connected curves".

A nice candidate for an RH style amp, in beam tetrode mode, of course - but what about the intrinsic sound quality of this tube? Does it have anything to do with the beautiful linear curves?
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IslandPink
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#3

Post by IslandPink »

I just put it out there for anyone interested in making a cheap good-sounding amp, as they only cost a fiver each . Then if someone makes it, we can find out if they sound 'very good' or 'great'. Apparently my posting wasn't aimed at you .
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#4

Post by Alex Kitic »

The post was not aimed at me - obviously.

But as far as a cheap and cheerful amp is concerned, the link does not lead to a schematic for such an amp... just nice pictures of a compactron tube and it's assembly.

That's why I reacted.
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pre65
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#5

Post by pre65 »

Alex Kitic wrote:The post was not aimed at me - obviously.

But as far as a cheap and cheerful amp is concerned, the link does not lead to a schematic for such an amp... just nice pictures of a compactron tube and it's assembly.

That's why I reacted.
Chill out Alex. :wink:
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Greg
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#6

Post by Greg »

pre65 wrote:
Alex Kitic wrote: That is why I reacted.
Chill out Alex. :wink:
I think he meant 'responded' which would be much more appropriate and not require the 'chill out' comment.
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Mike H
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#7

Post by Mike H »

A few assumptions here ~ no schematic 'cause it's assumed someone will design something or modify an existing one ~ and the tube may sound pants actually :D

Only one way to find out...
 
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#8

Post by IslandPink »

It's not going to sound 'pants' with curves like that !
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#9

Post by Alex Kitic »

Greg wrote:
pre65 wrote:
Alex Kitic wrote: That is why I reacted.
Chill out Alex. :wink:
I think he meant 'responded' which would be much more appropriate and not require the 'chill out' comment.
Correct: "to react" has a different connotation in my native language, and thus in my view. "To respond" is when you answer to a question your teacher asks. "To reply" is to answer to a specific request (a letter addressed to you).

As far as pants and curves go, "don't they all"? All triodes and triode connected beam tetrodes/pentodes exhibit more or less high linearity in the "higher part". We need to know the scale of the curves plot. What good is linearity at 300V 100mA for a 15W dissipation tube?

Further to that, in my view beam tetrodes and pentodes are superior to triodes, particularly if in the correct application (schematics). When I look at a 300B, I wish it had a screen grid for me to use as a lever and improve on what we have. Thus I view triode connection for beam tetrodes/pentodes as some sort of mutilation, and envisage ignorance as the cause (we did not know what to do with it, so we cut it out).

Last but not least, if anyone has a few of these tubes and nothing better to do, a modified or even unmodified RH84 rev2 is the right schematics for the task: exploit the extra few W of anode dissipation by increasing the current draw, or the B+, depending on the OPTs at hand... That one is guaranteed not to be pants, and might even be a revelation, who knows?
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#10 Is the advantage "vintage" or performance

Post by rowuk »

I have been watching Thomas for a long time. His niche is "cool" tube amps not necessarily the best possible performance. We all know that just by paying attention, very good results are possible with many topologies.

Triode designs get the hype of linearity and "musical sounding" distortion. My experience is that SETs only really perform if the speakers are suitable for the amp for connected and only need to handle limited bandwidth. If wide bandwidth is required, they simply do not deliver as much as is "published".

Thomas is building ultimately saleable products considering the demands of customers in this category. Whether his customers really are after the "ultimate" sound is questionable to me. In any case, I really enjoy the "exposure" to many of the sleepers that he turns into one-off amps.
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