Very inexpensive power amp kit?

[royewest]

My goddaughter has started listening to vinyl and I'm hoping to set up a system for her room. I've started lurking in used places, ebay, garage sales, Goodwill, etc., but am also wondering if there is a simple tube system I could build for her. I can build a Quickie for her for a preamp. Her Dad has a phono stage she can use. So I'm hoping to find a kit or plans for a power amp for say $100., but I'm a little flexible.

Thanks in advance on any leads.

 

[HF9]

Phew, that's a toughie. tube amps are usually on the pricey side because of the iron (you need the power transformer and two output transformers). The DIYTube Budgie SE comes to mind. If you punch and drill your own blank chassis, you could get the cost down to $220-240. It's not a kit per se, just a circuit board, manual and bill of materials. I'd imagine if you have a few parts laying around you could get under $200 fairly easily. 

 

[Paul Birkeland]

For ~$30, the T-amp will get the job done for you, and you could build in into the same chassis as the Quickie.

 

[Zimmer64]

T-amp integrated into the Quickie has been done before by Fleawatt : http://www.bottlehead.com/smf/index.php/topic,3623.msg32238.html#msg32238

I have also built 2 T amps from jerry's Electronics. The are a steal for that kind of money. Check out Fleawatt's blog beforehand. He upgraded the caps, which I have tried and it is really worth the extra bucks, and recently he also upgraded the inductors.

Another idea might be a gainclone, if you need a bit more umpf. Chipamp or audiosector. I have built both and the are good too. I use them with the Quickie as pre. All you would need to add is a toroid. My recent toroids I got from Poland http://www.toroidy.pl . Very good price for a shielded and epoxy filled toroid. I was a bit sceptic at first, but they are reliable.

Enjoy.

Michael

 

[matthewmckay]

for the gainclone... (besides a toroid), you will also need a chassis, rca sockets, binding posts, wire, iec inlet, fuse holder, etc.  (and as an option, a potentiometer)/
  -these things will all add to the cost.  my GC kit from audiosector ended up running around $225.

 

[Chris]

Yeah , I ditto about the tube amp idea being TOO cheap just leaves you with  a high voltage circuit on an open breadboard  type thing which IS dangerous and will still run you over 2 benjies and sound maybe suspect. Better to wait and see how it goes with her and then plunk down on a REAL tube kit like the SEX later.... (just dont tell her that its called SEX...haha )... For now, like PB said, an inexpensive t amp will give her more power, good sound and is very cheap for her to get her "feet wet" with.... And as/if she gains a desire for more refinement later, then a bigger investment will feel much more comfortable...

 

[4krow]

I would have to agree with the T amp idea. Sure there is always better, but not much at that price. I use one for my garage system, and another for my test bench. I would be willing to guess that the Q is of a bigger influence to the sound than the T amp. You are probably going to be pleasantly surprised at the sound.

 

[royewest]

I really appreciate all the advice so far. Thanks!

 

[RayP]

I would second the inexpensive T-amp idea. My daughter lives in Sydney and when I visited her last year I built a pair of Frugel-horns for her and also bought her a T-amp to power them. She has been very pleased with the results and apparently gets lots of questions from visitors who are quite impressed with the sound and the looks of the speakers and amp.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=310-300

For a bit over $20, you can't go wrong.

As others have mentioned, you have to spend about $200 to build a tube amp. It can be done for less but it is not easy as we found a few years ago for our 'build a 6V6 amp for under $200' competition.

http://audioratbag.blogspot.com/2012/02/bottleneck-6v6-competition.html

ray

 

[jrebman]

Yes, another vote for a good t-amp, especially with the Quickie as front end.  I like the one  from Jerry'selectronics mentioned and linked earlier in this thread.  Once you make up your mind, you can drop me a note of all the ancilliary parts you maight need -- binding posts, rcas, caps, poer inlet, etc.  I have tons of this kind of sstuff lying around and you're welcome to whatever you need and I have.

In fact, I also have plans to build a budget amp with the Jerry's board and the quickie, and all in one chassis, but that's pretty far back in the queue.

-- Jim

 

[Wanderer]

I have a Quickie and one of the original Sonic Impact little T-Amps. Together it makes a very decent sounding combo driving some Linaeum tweetered Radio Shack Optimus LX-4.

The Parts Express unit is pretty much the same unit. There are mods around for T-Amps if you Google them.     

 

[Grainger49]

I hadn't thought of a T-Amp but I have heard them. Not bad, not as good as a GainClone.  But it fits the price bracket.

 

[rif]

I have the lepai amp mentioned above. Currently use it in my garage and couldn't be happier.  IIRC, there are a ton of threads on other forums for tweaking it.

 

[royewest]

Thanks again for all the advice on this thread.

I built Jerry's stock T-amp this afternoon and connected it to some ancient and inefficient Fried bookshelf speakers, with my cell phone and an album I uploaded to Google Play as FLAC as a source -- simplest way just to see if it produced sound.

Ya know, this is just astonishingly good sound. Some cymbal shimmer missing -- BFD for 30 buck or whatever and not even lossless source (Google Play downsamples your FLACs when you stream them).

I'm working on a Betsy order and am awaiting a Quickie kit.

One thing I did notice. At first I used an APS 15V transformer as the power supply and the noise was pretty disappointing. On a hunch, I replaced that with 2 cheap 9V batteries in series and the noise disappeared. Now I'm researching battery-based power supplies...

 

[4krow]

I'm a big battery powered fan...it's cooool man. pun intended. Batteries are almost the best any time you can use them. They are partly what makes the Quickie great, and I think you are on to something with your idea as well. Keep us posted. Now where did I put that extra battery pack?

 

[earwaxxer]

I'm with you guys on the battery power! - My first foray into battery powered gear was running my 50wpc t-amp on a 30V pack. That was great fun. That little bugger was not the end all in resolution etc, but the battery definitely sounded 'smoother' than the SMPS. 

 

[Wanderer]

My fault for not checking the links - the Parts Express unit that is a clone of the Sonic Impact is this one -

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-380

 

[rif]

My fault for not checking the links - the Parts Express unit that is a clone of the Sonic Impact is this one -

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-380

Or get the dta-2, which is the bare guts of a dta-1

www.parts-express.com/pe/showdetl.cfm?partnumber=300-385