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Nice Baby Huey EL84 Amplifier

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Joined 2015
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I started this project over a year ago and got sidetracked multiple times. Recently finished it, the amp was working fine but I was probing around and may have shorted something which resulted in one channel not working properly. Initial trouble-shooting shows incorrect plate voltage for the ECC83, I believe this shouldn't be too hard to fix.

Due to that, I am asking $450 shipped for this amp !
Cost of parts was between $850-$900.

Very high quality build, Hammond transformers, CNC milled chassis, powder-coated in gold (resembling some of the older Leak amps), Azuma tube sockets ($7/ea), Vampire binding posts, NKK switches etc. Toggle for 4/8 ohms, either of which can be swapped out for the 16ohm tap, regulated DC heater module.

Feel free to reach out with any questions
 

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Joined 2015
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Thanks dBel84.... I priced this fairly low compared to the cost of parts so a bit surprised no takers yet.

Anyhow, I re-tested this yesterday and the hum was actually very low, on par with any other amp I have so I'm not sure there is an issue at all.
In addition, I bought a Jensen Iso-Max CI-2RR to test the possibility of ground loop and indeed with the Jensen it is silent, so if anyone was on the fence you can buy with confidence that this is a working amp.

Here are some frequency plots I ran, one is zoomed to a 5dB window. As measured, 20hz - 20kHz is within a 0.5dB window so overall very nice IMO
 

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Joined 2015
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Very nice build! You price is a steal - someone is getting a great deal. Good luck with your sale.

Looking at your photos it appears that you are using an AC heater supply. If this is correct, a DC supply will likely stop any noise.

Correct, I used AC as I read comments of this working fine for most folks. Generally AC should be OK for EL84's, I've had success using AC with the RH84's and the Tubelab SPP.
The hum I experienced was due to a ground loop (as it was cleaned up with the Jensen input transformer), but I do agree that using DC won't hurt and may even make things quieter. There should be sufficient room in the underneath to install one if someone wants to experiment

Stunning build quality! Very inspiring....

Thank you!
 
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Joined 2015
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The hum was actually fairly low and my speakers are fairly efficient so maybe not really a problem, but I ended up trying a few things, such as adding a regulated DC heater and moving around some wiring and I may have shorted something on one of the boards as now I can't balance the input tube on it.

I don't have much time to deal with it so will knock off another $200 from the price, and will ask for $450 + shipping (excluding the tubes).
That is less than the transformers and chassis, but it is sold as-is.

If I have time in the short term I will fix it myself but then will go back to the previous price.
This is the latest state of the amp with the regulated DC module.
 

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That is a really good deal. I've been collecting parts to build a BH84 for several years now, sorting through various parts bins at the local surplus electronics store (alas, it is now closed, rent is too high everywhere around Silicon Valley). I'm so so so tempted to buy, But have to keep reminding myself that I get to pay for this hobby after taking care of other bills in life. Wish both the seller and whoever does get this great deal good luck with this sale. Would be a ton of fun to get this amp to sing....