New EL84 amp kit build :)

JakeJ · « **Reply #40 on:** 29 Dec 2025, 04:55 pm »

Beautiful! Love the color choice, root beer brown?

nlitworld · « **Reply #41 on:** 29 Dec 2025, 05:59 pm »

Yep, PPG Copper Penny pearl base, then a pearly root beer candy over the top. The joys of having a paint shop in your garage is finding all the rediculous fun colors. My hope was to make it interesting and blend into the background at the same time.

nlitworld · « **Reply #42 on:** 25 Feb 2026, 02:21 pm »

Just wanted to give an update on this amp build. Last night everything finally finished clicking together with getting proper amount of burn in and it sounded absolutely astonishing. Clear, articulate and snapped with authority but was completely three dimensional that I've never had to this level before. Getting depth of soundstage in my very small room is tough but last night proved why this amp freakin rules.

After cleaning up the internal wiring a bit, things are much better but I do still get a tiny amount of buzz from the tweeters. It's not really noticable at the couch and I believe that has more to do with the power in my house than anything to do with the amp as every other amp I've used has +/- similar results. All in all, I can't recommend this amp kit enough as it really hits a home run on every level. Go buy one and deck it out to the 9s.

Tubes4HiFi ST35

MosDeaf · « **Reply #43 on:** 25 Feb 2026, 05:30 pm »

You really did a phenomenal job..it's beautiful.

I have one as well that I upgraded with higher quality parts..though I only upgraded the first cap 20uF cap in the power supply with a poly. I also have some fuzz still coming from the tweeter..not noticeable with music or without my head near the speaker. Other than that I completely agree with you on how this amp sounds & performs.

Can I ask which Schottky diodes you are using?
Thank you. And again, fantastic job. I want to redo mine now

nlitworld · « **Reply #44 on:** 25 Feb 2026, 05:52 pm »

I used Vishay 6A TO220AC ones HERE ON DIGIKEY. Not sure if that's the most correct one to use, but it's what I tossed in there. I know the job they do, but I'm unsure as to which specs to keep as a minimum level and which are overkill. If someone knows a little better, I'd be all ears to understand what's what with those diodes.

Tyson · « **Reply #45 on:** 25 Feb 2026, 07:34 pm »

This is consistently my 2nd favorite amp out of the 13 I own. Really great sound and it punches way above its price.

nlitworld · « **Reply #46 on:** 26 Feb 2026, 01:23 am »

Quote from: Tyson on 25 Feb 2026, 07:34 pm

This is consistently my 2nd favorite amp out of the 13 I own. Really great sound and it punches way above its price.

But what's #1?

FullRangeMan · « **Reply #47 on:** 26 Feb 2026, 01:28 am »

For those who like EL84 tube there is this SET amp, 3W, $1095usd, UltraLinear not Triode.
https://wrightaudioarts.com/mini-amplifier/

Tyson · « **Reply #48 on:** 26 Feb 2026, 03:15 am »

Quote from: nlitworld on 26 Feb 2026, 01:23 am

But what's #1?

#1 rotates pretty much constantly. But #2 is always the EL84 amp. I know, that's weird. But there it is.

nlitworld · « **Reply #49 on:** 26 Feb 2026, 05:02 am »

The best non-answer answer and one any true audioholic understands.

I guess that's proof of the staying power of this amp to always be a solid #2.

FullRangeMan · « **Reply #50 on:** 26 Feb 2026, 05:05 pm »

If there is a half dozen first place amps, second place is not so much.

Tyson · « **Reply #51 on:** 26 Feb 2026, 06:21 pm »

Quote from: FullRangeMan on 26 Feb 2026, 05:05 pm

If there is a half dozen first place amps, second place is not so much.

Oh I meant that first place rotates, not that a bunch are tied. For example, a few months ago I picked up some Sophia Electric 300b monoblocks with the WE style OPT's. That was my favorite amp for a few months. But the 2nd place amp was the EL84 amp. More recently got a super vintage Type 45 amp and it's currently my favorite. The EL84 is still 2nd. And I have an even newer amp (2a3 SET) that will likely be my favorite once I get it some time in the system. But EL84 will still be 2nd.

If I could only own 1 amp, it would be this little push pull EL84 amp, as I consistently love its presentation. Luckily I don't have to choose, I have a bunch of different amps at this point.

FullRangeMan · « **Reply #52 on:** 26 Feb 2026, 07:22 pm »

Thanks for inform us

How do you rate a good EL34/KT66 SET amp ?

Tyson · « **Reply #53 on:** 26 Feb 2026, 07:38 pm »

Quote from: FullRangeMan on 26 Feb 2026, 07:22 pm

Thanks for inform us
How do you rate a good EL34/KT66 SET amp ?

For pentode amps, I like the KT66 tube best of all, better than EL34's or KT88's or even KT77's. And I have a very nice push pull amp using KT66 tubes. I'd say for most normal speakers with mid-to-low efficiency and non-flat impedance, it's the best choice.

FullRangeMan · « **Reply #54 on:** 26 Feb 2026, 08:00 pm »

Wow great, Thanks

MosDeaf · « **Reply #55 on:** 17 Mar 2026, 01:41 am »

@nlitworld if you are still having some noise (& if you aren't already hooked up this way) take the Black & Yellow wires from the OPT & tie them directly to the 8ohm & Grnd on the PCB. Then from there straight to the speaker jacks. Disconnect the green wire as well from the speaker jack.. just cover it and tape it down inside.
Also the chassis & ground tab near the power supply. I went straight from that chassis tab to the chassis & put a Ground Breaker between the PCB tab & the chassis. A 10ohm resistor in parallel with a 0.1uF cap. I also grounded the IEC jack to chassis..no ground breaker. Made a great difference for me. I might try adding a Heater Elevator next.

nlitworld · « **Reply #56 on:** 17 Mar 2026, 02:18 am »

Thanks for the details on that! The little hum is not entirely gone, but it was certainly diminished with some tidying of the wiring inside. Now I can barely hear a low zzzz with a quiet house and no music. A while back I did go in and twist the wires of the film caps, tucked the coupling caps in a little tighter, cleaned up the opt and feedback wires, and twisted tighter the power wiring all made a good little bit of help. I see what you're saying with eliminating the small loop regarding pcb->opt->feedback pcb. Also I'd be curious to see a photo of your ground breaker wiring as to where you have that connecting to. Right now I have everything off the same chassis ground point, but that is likely my biggest gains on where to tidy up.

To be fair, I'm fully understanding there could be a few other sources of the tiny zzz I can hear. House wiring with small dc offset, NOS power tubes having a little noise to them, other component tubes being noisy, and gear ground loops all could play a tiny part in adding up. I've never had a dead silent stereo of any configuration, so as it sits right now it's the best it's ever been.

MosDeaf · « **Reply #57 on:** 17 Mar 2026, 12:26 pm »

I just did this yesterday & the resistor lead is basically just laying across the Chassis tab with a smidge of solder. I'll tighten everything up when I get everything complete. My wiring from the OPT to PCB is sloppy at the moment as well but I was just trying things out. Your build has encouraged me to go for a better chassis & top mounting the transformers.

From your description it seems as if your unit is pretty quiet to begin with. Mine seemed as if it was getting noisier. A better way to describe it is that my noise level was inconsistent.. some days louder than others or depending on the preamp being used. My transformers are mounted internally though & due to space I'm unable to route my High Voltage & Heater wires close to the chassis. I was worried that some of my noise was the power tubes picking up noise emitting from the wiring.

I'm not dead quiet but the noise I hear close to the tweeter seems to be only tube related now. I've only had the amp playing thru my test system but it's a bit quieter than before. It was never anything I could hear from the seated position though.

nlitworld · « **Reply #58 on:** 17 Mar 2026, 01:18 pm »

Oh that looks easy enough. For your iec plug, do you just have another short wire connecting chassis to ground right at the plug then?

Unfortunately for me, my room being only 10x12 puts listening position only 5' away so any noise is basically just as loud at the couch. I'll see if there's a way to work out this ground snubbed scenario and rework my grounding scheme.

Also, your build is super clean and looks like you've already done a lot of the best upgrades with film cap in first power filter and around the ecf80 tube and pio coupling caps.

MosDeaf · « **Reply #59 on:** 17 Mar 2026, 05:37 pm »

You can see in the photo where the Blue Wire (had no green) goes directly to chassis. What's also in the photo is the purple wire from the power transformer still connected straight to IEC. We want to connect that to chassis as well. Just pull it out and tie it to chassis. I had to add wiring because it was cut so short.
The best layout would be to give it its own connection to chassis with the shortest path possible. You should be able to connect it at the same spot as the safety earth (Blue wire to chassis in the photo) with no issues.. but giving the purple wire it's own connection to chassis is ideal. No need for a "ground breaker" here.

The purple wire in this power transformer is the shield. It could be carrying noise from the transformer. Leaving it in the IEC it could drain noise into our chassis via the new safety earth connection.

IEC Earth - chassis
PCB Ground - chassis (via ground breaker)
Transformer Shield - chassis

Try to keep them away from the input jacks or wiring the best you can for optimal results.