Tube 6N3 Preamp TDA7294 Power Amplifier Kit DIY 80W+80W

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If it says a 24v-0v-24v AND 9-12v then that is what is needs , it doesn"t say 24v-0v-24v and 24v ........

The 24v-0v-24v is used for the Poweramp and the Plate of the Tube , the 9v-12v is used for the heaters which is regulated to 6v with a lm7806 ....... if you use 24v you will fry the regulator .......

Get a transformer with an extra 9v-12v winding or use a seperate small transformer or even an AC wallmart ......
 
That kit in stock condition is not very good, but it can be upgraded to passable imaging and a pretty tone:

Regular Chinese 6n3 is poor because it might block clarity. It can be upgraded with Russian 6n3P, 6n3p-E, 6n3P-EV to install higher quality.

The datasheet example design for the TDA7294 has so many problems, poor tone, hot running and unstable. I've posted more stable design on Bob's Optimizing TDA7294 thread and also my Parallel TDA7293 thread. That better schematic (a few different resistors and caps) will help the chip run more stable, much cooler, nice tone and sound clearer (those are mostly stability related features). So, go find the better schematics if you want it to work well.

At least the price for upgrading the kit is not expensive.


Usage optimization for this 6n3p+TDA7294 kit is interesting:
The kit's design is maximum for tone, minimum for imaging, midfi resolution, so the usage of it is for where tone is more important than any other audio amp feature. Here are some possible ways to use it.

Bad Uses:
It isn't optimal for speaker building
It isn't optimal for analytical hi-fi
It isn't optimal for use as measuring equipment

Good Uses:
It can be used in a very good Guitar amp
It can be used for background/office music
It can be a pleasant sounding Television amplifier
It can be used for replay of HD Radio

Other use:
With a different schematic, such as 100k feedback, 2k7 feedback-shunt, 220u//10n NFB-shunt-cap, and the main signal input caps smaller than 1u, (and the Russian tube upgrade) this kit can be re-purposed to a small prosound "mids&treble" amp for driving arrays of small midranges and tweeters in up to medium venue size areas, such as a nightclub. For either production or replay, this sort of amplifier and mids&treble arrays can stabilize the sound so that singer's voices aren't shaken up by the cone excursions of large midbasses and woofers. If nicely done, I believe that the "tone first" nature of this kit can sound posh and modern for tone, if you choose to build it that way.
Also, if you have a subwoofer available, you could try the mids&treble amp option at home to power a pair of modest size speakers. It would probably be interesting for karaoke!
 
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Hi danielwritesbac :)
I bought this kit specifically to make a small guitar amp out of it. However i found that there clearly isn't enough gain from the preamp to amplify the low signal produced by a guitar pickup. In fact i had to connect a very high gain preamp pedal in order to get some volume from it... Is there any way i could modify the preamp section to produce more power?
Thanks :)
 
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