Hybrid Amp Project (inspired by nzCdog's Lil Watter and Orange Micro Terror)

[nzCdog]

Looks cool hector... good luck fine tuning things!

[Ettore_M]

Hi there! 

I'm quite excited today, because I discovered that all the boards are working! The pre-amp board causes a little hum, but it's not in a box yet so I think this will stop once I box it.  BTW, with a 12AX7 at 100 volts, there is a whole lot of headroom available. Or so it seems to me!

However, it seems like an overkill having a full tonestack on soemthing like this. So I think I'll maybe get back to the Boobtube as a preamp stage.

The past days, the pre-amp didn't work, when I tried it in front of the TDA power-amp. Today, I tried it in front of my amp (like a pedal) and it works! So now, I think that this little thing needs more than 850mA that my 12V supply can give.

Also, the heaters are now working on 6.3 volts supplied by a LM317 and the tube doesn't get really hot and the tube will have a longer life. However, the LM317 does get really hot, even with a heatsink!

That's all for now! If there is someone with a little more knowledge than me on tube preamps, and wants to give an advice or two, you're welcome to chime in!

Hector

[Ettore_M]

Holy F#%K! 

This thing works! I am surprised. The picture below shows why!



It actually works. At least, I didn't expect it to behave well at all. But I got great sound from it. It sounds very tube-like, because of the tube preamp. And the TDA2050 gives a lot of power! I think it can get to volumes equal to my all-tube VHT Special 6!

However, I have a lot of noise..  I'll figure it out later. But as a proof of principle, I think this little amp can be a great amp project, and could be used, not only for practice, but for gigs too. I know a little optimistic, but with a mic'ed 12" speaker cab, you could cover the needs for a little bar gig.

Hope you can actually understand my words. I'm too tired even to think. I'm excited, though! 

Here's a sample! It sounds like crap. I put the mic too far away from the cab, and there's an extreme amount of noise. But, I hope you like.. 

[soundcloud]https://soundcloud.com/ettore_m/hybrid-amp-test[/soundcloud]

Hector

[selfdestroyer]

Very cool. Looking forward to seeing more of this. Looks like a fun project.

[micromegas]

Sounds really nice and I happen to need a new practice amp (my Mark II Boogie is to loud for home). If only the noise could be reduced somehow...

[Ettore_M]

Hi guys! I'm happy you like it. I'm going to fix some things that may cause noise, and I'm going to put it in a box, as now it's out and a circuit like this catches a lot of RF or 50Hz noise. I think it's gonna be just fine.

Note that the schem is not right as it is, as I changed a couple things. So, wait a little for the new one, if you wanna build one!

Hector

[Ettore_M]

Finished at last! And it sounds huge! 



I like it a lot. And volume-wise, I think it gets really close to my VHT Special 6! Pretty awesome! 

I'll record a sample for you! I think you'll like it a lot too! 

Hector

[selfdestroyer]

Awesome, great job.

[gtangas]

nice...very nice!!!

we need more updates on this! hehhe

[nzCdog]

Well done mate... the demos sound great!   

[maiko]

I know its an old thread but how did this project now.   did you update it?   Im very interested