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Cheap Chinese 6P3P kit

apurcell22 said:
I would suggest building it and taking lots of pics for those who wish to purchase it.
Al
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Totally agree.

AND Ray, I also suggest you find someone who is very good with English composition. And it doesn't have to be an American, Canadian, Brit, or any Westerner. All you need is to locate a Hong Kong resident, who grew up under the Brits. It is vital that you do this IMO.

Chinese and English are almost totally the opposite of practically everything. English reads clockwise; Chinese counterclockwise. Structure is not the the same. Inflections are different. Tenses are different. Its all different, and anyone proficient in English immediately knows when a non-English person is attempting to communicate. And I am not using any racist/nationalistic thinking here.

Like it or not, English is the world's second language. With compositional English down pat you can, and really need, to put out detailed instructions on how to put each kit together. The first Chinese company to do this will have a 'leg up' on the competition. And from what I can tell, there isn't anyone there yet.

Pardon me for jumping in, but I find this to be the most serious stumbling block to a pleasant experience.

And having lived in England, as a military dependent, I prefer King's English most. So I am not promoting 'all-American' here.
 
siliconray said:
Planning a low cost verion phono amp kit. First think is using RE2205 as enclosure, 2 stage 6SN7 (6N8P) for amplification, RIAA equalized, DC filament power supply, about 150 gain. What's your thought?
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Myself I would actually go away from octals.
As the only tube your going to be able to use would be the 6SN7 or 6SL7.

Going to a 9pin dual triode opens up a whole host of possible tubes to run.

Also I would think about using a high trans-conductance signal pentode, as
there generally quieter with less input capacitance as well as "high gain" so
you may be able to get away with 1 gain stage then maybe follower output.
 
After all the stress with my kit I have learned so much, I want to jump back in again LOL Yes a phono preamp would be great! and I would follow the advice of the members on its design. If you can get the kit's with better instructions and photos. You have a winner on your hands
 
Count me in too... I like the Idea of one with 6SN7's. There are Plenty of Them out there to Roll...And, I've already built one with 6DJ8's...
 
Hey Tanner...6V6's are the Way to Go with This...I just put in Jan Sylvania 6V6GTY's, and they have a 'Nicer' Bottom and Mids...With any Luck the RCA 6AU6 Black Plates will get here Soon...That should Show me how This really Sounds...
 
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SiliconRay should List This as being a 6X5GT, 6AU6 & 6V6 Pre-Amp, also...There are a Ton of these Tubes to Roll in This...
 
In case you felt like messing around after it's built.
------------------------------------------------

You guy's wanna try an interesting/neat/easy mod?

Running just the triode strapped 6V6 an no feedback.. :smoke:
(gain will be lowered and no feedback, yu might like it)

Pull the first tube out(the 6AU6 or whatever your running),
then run a wire from the volume pot on out to the 6V6 grid.

.
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John L said:
Could you please explain the purpose, and the result? I don't know the exact reason for this.
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Negative feedback is a process of sending a reduced strength signal back to the input device as a "correction signal". The original device then "corrects" for differences between the output signal and the input, essentially "pre correcting" for distortions created by the device. This is the theory behind it. Some people like the effects that this brings to the "sound" of the amp and some think that amps sound better, perhaps more musical, without it.


Hope that helped.

Shelly_D
 
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Kegger said:
You guy's wanna try an interesting/cool/easy mod?

Running just the triode strapped 6V6 an no feedback.. :smoke:
(gain will be lowered and no feedback, yu might like it)

Pull the first tube out(the 6AU6 or whatever your running),
then run a wire from the volume pot on out to the 6V6 grid.
Click to expand...

A variation on the mod that Kegger is suggesting is to use a DPDT switch to switch between normal operation and no feedback. The circuit would look like this:
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Kegger:, please forgive the presumption.

Shelly_D
 

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That is a fine example Shelly.. :)

The only slight thing I'd like to say is the mod I was suggesting wasn't as much
NO FEEDBACK, but that you went to a single gain stage, just there triode wired
6V6, the fact that you take out the first tube and it takes the feedback with it
was just a "byproduct". ;)

So the mod I was suggesting was just going with single gain stage instead of 2.
(but taking out the first gain stage also took the feedback loop with it as well)

And that triode wired 6V6 has low gain/plate resistance, good preamp Qualities.
 
Depends on a few things..

A: no not if you happen to leave the 6AU6 in, as you'll have dc voltage at that
connection feeding the 6V6's grid, (the 560k bias resistor to the 6au6 voltage)

B: yes if you don't mind another cap being in the signal path or have dc coming
from your source, and you always make sure the 6AU6 is not in there.

C: no if you don't want another cap in the path an you have no dc coming from
your source either.

Me, I'd leave it just as drawn, as I don't want another cap in the path if I don't
have to, an the pre can run with an 6au6 in as well, source should not have dc.
 
Better to couple signal in front of input capacitor. I think one stage amp is enough for most sound system to.
The next stage must have high impedance with NFB design.
 
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