Alright, time for Giveaway #2! This prize rocks. It is two mono kits of the MyRefC LM3886 chipamp kits that Uriah and Peter recently put together (a very large effort - thanks guys) as part of a groupbuy. The chipamp design is by Mauro Penasa and it is well regarded (see the schematic at the bottom of post). Also included in the giveaway are two 160VA (120V primary, dual 24V secondaries) transformers that will work well with the amplifier modules and allow you to build two mono-block amplifiers if you like. To finish off the kit, you will need to supply your own hookups and bits (RCA, Speakers, IEC, power switch, wire, ...) as well as a suitable heatsink and chassis (or two).To enter the contest, all you need to do is post one message in this thread with one or more photos attached (maximum of 6 photos in the post and the max file size is 250kB each). Please include a brief description of the photos. The photos should be of some diy audio project that you have built or are building. There will only be one winner and the winning entry will be chosen at random (a random number with the winner selected by message #). The next time we do this, we will set up some sort of voting system.

Questions or comments related to the photos or the contest should be posted in this thread: Discussion - Giveaway #2 - MyRefC LM3886 Chipamp Kit.

Giveaway Rules:

• Please do not enter if you will not build and use the amplifier.
• Only one entry per person (do not post more than once in this thread).
• Contest Ends April 10, 2009 at 18:00 (CST) (UTC-6).

We will announce the winner in this thread and make contact via email to get the winners mailing address.

New Members - please note that new members are under moderation (to keep spam off the forum) so your posts will not show up until it has been manually approved by a moderator.

Good luck!

Build Logs of the MyRefC LM3886 Chipamp Kits

• Mauro Penasa MyRefC build by Uriah
• LM3886 MyRefC Chipamp Kit build by Gio

I recently have build a 160Liter Bass reflex Subwoofer with the Mivoc AWX 184. In three months when I move to my new house I will build the corner horn 18. I am looking for a good but inexpensive tube amplifier at the moment, so I decided to give this a shot. Unfortunately I don't have any pictures of the finished projects, but you can see it at:

Wolfgang

This is a MIDI controller that I created for a friend of mine, using a homespun arduino on a protoboard, and several 4051N multiplexers.

It performed well in the lab, but ended up being a bit wonky when under heavy use. I believe the problem is that I used super cheapo pots and they just don't have the tolerance that the project needs. I thought I could get away with using cheaper pots as I wasn't running any audio through them, but it just didn't work out right.

The platform is solid though, and the buttons work perfectly. There's not a whole lot to the Arduino code, and I would be happy to share it with anyone that asks. It was a great proof-of-concept, and I plan on building another controller in a proper case with less pots, more buttons, and maybe even a couple sliders.

There are lots more pics in my Flickr album.

Hi,

Hope the pics are there

This is an amp I have built recently using the Philips TDA8920BTH. Even though it sounds very good I'd really like to try this Gain clone, it is actually very different than most GC I have seen.

Regards,
Eric

Here is my recent S5 electronics K-12G, I'm just getting into this hobby.
I don't yet have the enclosure built, but here is a top & bottom view.


Thanks for the chance!

A shot of some of my CMoy headphone amps. These were how I started down the DIY route. Quickly tired of the regular Altoids tins and tried several variations of the theme. Also built a Millett Hybrid in a really sweet cigar box before advancing to chip amps and now full fledged tube amps.

Love DIYin'!
Cheers, Greg

I modded my Korg EX800 (the tabletop version of the poly800) with the MoogSlayer Filter and FM800 mods. I also added a top mounted noise control.







The difference in sound and flexibility of this synth is amazing. I'm very happy with the overall build. I used high quality pots and resistors from pedalparts.com - my next project is to mod my casio VL-Tone and to apply some crazy warranty voiding bends to a cheap Berhinger Reverb Pedal that I got for free.

check my other projects: http://containthecontainers.blogspot.com
my band, all 4track, all the time: http://www.moonmissiondeathsquad.com

Hi all,

I Just realised that the add file button is below so................... I added a file

Elsinore Speakers 3/4 finished.

-Dan

Velleman K8060 Amplifier kit in the making...hopefully it'll be a good one.

I have some neat project pictures I can post, and I think I will start with my 50EH5 / 25EH5 tube amplifier, now that I have some very nice pictures of it. I have to say, this was one of my most successful projects so far.
I plan on making a pair of efficient speakers for it at some point, but for now I am going to attempt a custom wind of a toroid core that I pulled from a blown car amplifier, hope fully the core is big enough to get 25V-0-25V, less if I run DC filaments at 300mA 50V.