diyAudio - DIY 5 Watt SE Guitar amp kit

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DIY 5 Watt SE Guitar amp kit

I built a really nice sounding SE EL84 amp a few weeks ago into a combo cabinet. The kit was just $215 from MODkitsdiy.com, I got it from Amplifiedparts.com. This does not include the speaker.

It comes with a 10 x 6 x 2 grey painted chassis so I put it in a Hammond 1444-18 (13.5 x 5 x 2) style chassis so I could mount it in my existing cabinet.

Here's my build and review link with video clip.
Kit Review: MOD 102 DIY Guitar Amplifier Kit | GuitarKitBuilder.com

http://i238.photobucket.com/albums/f...Photos/002.jpg

http://i238.photobucket.com/albums/f...Photos/004.jpg

I put a Plexiglass back panel on to make the insides viewable and safe.
This amp makes a great teaching aid because being point to point, it relates easily to the schematic.

http://i238.photobucket.com/albums/f...hotos/102T.jpg

Nice. The grill reminds me of my grandma's rocking chair.

Quote:

Originally Posted by Cassiel (Post 2669412)

Nice. The grill reminds me of my grandma's rocking chair.

Your Grandma obviously has great taste in rockers. ;)

Quote:

Originally Posted by Casey4s (Post 2669767)

Your Grandma obviously has great taste in rockers. ;)

At the risk of being sexist, I'm presuming you're a woman, I can't imagine a man cutting a heart in the back of a guitar amplifier :D

All well and good, we need more women in Electronics (and in music).

Quote:

Originally Posted by Nigel Goodwin (Post 2669823)

The heart is in memory of my Wife who died of cancer after 31 years of marriage. All of my cabinets now have the heart.

Thanks for asking.

Wow, that's really touching. Good on you for keeping her memory alive.

(Great review, BTW.)

Quote:

Originally Posted by Keriwena (Post 2670334)

Wow, that's really touching. Good on you for keeping her memory alive.

Yes, very touching - nice to hear about.

I am not so interested in what you guys think about the container.

Did any of you listen to the videos? If so what about the versatility of this super simple 5w kit amp. I didn't design this circuit so feel free to disilike the tones etc. The two guitarists are 16 year old students so please be kind.

Honest criticizm is the best kind...

Nigel,

I hope you and your family have been safe from the violence that is has been taking place there.

It sounds very good, how did you record it? Also, the schematic is WEIRD.
Uncommon plate and screen voltages and the heater wiring...first time I see that scheme. Hmmm....only 5.5 volts on the cathode. Not much clean headroom. Strange. I was expecting to see the typical Champ schematic....but nope. Well, it seems the el84 sounds better with lower voltages than typical on the plate and screen. Interesting.

Quote:

The third method is called "DC elevation" and the MOD 102 uses a variation on it by connecting one side of the heater winding to the cathode of the V2 power tube, which is biased to about 5.5 Volts DC. This floats the 6.3 volt AC heater voltage on all three tube filaments (two in the dual 12AX7 and one in the EL84) on top of the 5.5 volts DC. This approach minimizes the hum induced from the heater to the cathode because the induced current becomes close to a constant value when the voltage is above a threshold. In other words, although there is still leakage current, it is constant and therefore the noise voltage appearing at the cathode becomes DC, which is inaudible