Custom harp amp build completed

[MakerDP]

Hi everyone.

I just finished a build of a custom harp amp. It's based on the Fender 5c4/5d4 schematics with some tweaks here and there to modernize the circuit and make it as simple as it could be in terms of "just-plug-in-and-blow-ability." All in all, I think this thing turned out really "super" if you catch my drift

Rather than post all the gory details here and repost the same info on four different forums, I created a blog entry complete with a demo song featuring the amp and background info on why I built it in the first place.

MakerDP: "Sonhouse Super Harp" Amplifier Build


I'm not really a regular here and I hang-out mostly on AX84. However, since I got a bit of information for this build from this board I thought I should share this with you all. There is very limited information out there on harp amp building. Some of the info floating around the web is just downright not altogether correct so it's hard to sift through it all. MEF seems to be the best repository of original knowledge and pointers to other good sources available on the web, so here is my contribution.

So, thanks everyone for looking and/or contributing to this forum!

[tedmich]

Nice red tolex work! I like the odd angles (like many of the harp players I've known )

[arnenym]

Great job.
It's just one channel!.
Is the first tube parallell connected?

[MakerDP]

Great job.
It's just one channel!.
Is the first tube parallell connected?

Sorry for the late response...

yes the first tube is a 12AY7 wired in parallel.

Yes one channel with tone & volume. Tis all you need for a harp amp!

After using this live many times since it was built, this amp sounds great. Of course, the player has a lot to do with it but it was just what the doctor ordered. It sounds really fantastic and he can now keep up with the band without feeling like he's blowing his lungs out of his chest.

[arnenym]

How do your super clean preamp work for harp?

[MakerDP]

Most of the overdrive is in the power amp due to its cathode bias and no negative feedback loop. This provides a nice early breakup in the power section to help minimize feedback.

The key to the preamp is the 12AY7 with a fairly low voltage on the plates provides a nice early breakup. Also helps with reducing feedback since it can be achieved at lower volumes.

[arnenym]

Thank you

[Tone Meister]

My experience is lower volumes and harp players is mutually exclusive.

Yes, nice build although I'd cringe walking on stage and seeing an amp that size perched behind a harp player.

[DennisVeal]

Looks good!

[StephieJoe]

Oh God, can't imagine the weight) Looks really great!

[eschertron]

I had to look twice, and then a third time time before I realized the amp is sitting on a card table. The angles and lines led my eyes to believe it was a huge cab resting on the floor and towering over the kitchen countertop!

I know this is a necrothread, but I have to say it's a beautiful-looking piece. Are there any soundclips, or videos of the amp in action? That would be nice!

edit: just visited the blog page. Very nice!

[StephieJoe]

Me too! LOL
I thought amp stand on the floor. Now I see