18Watt.com

Hiya!

I’ve been busy lately building a single ended 6L6GC Tremolo TMB. So I finished the amp today. I had a reasonably loud hum that was caused by low filtering, which was the 2x 32uf can cap. When I add 50uf to the 1st cap section the hum is extremely reduced… so I will tweak on that part some in the next moments I will work on it.
Next job is a PCB reverb with LND150 mosfets.. I reserved room for that as you can see.
Soundclips upcoming!!

Well.. here's the schematic as the amp is built now.
I wonder though... I thought it would have like 10 watts, but I think it's way less. Sounds great, but I wonder if a PI circuit (adapted for SE) will give more volume?

There's no point in a PI, but if you want more gain, you could add another gain stage. Though that won't necessarily do anything for your overall volume.

Did you calculate the dissipation? I don't see enough voltages listed in your schematic.

JMPGuitars wrote: ↑

Fri 02/17/23 11:53 am

There's no point in a PI, but if you want more gain, you could add another gain stage. Though that won't necessarily do anything for your overall volume.

Did you calculate the dissipation? I don't see enough voltages listed in your schematic.

I’m not necessarily sure I want more volume.. it is a nice home level volume. Just wondering though.
Dissipation is good. It’s a 6L6GC 30W: Va 365V Vk 22.8V with a 270R 10W Rk/ 1000uf 50V cap

I saw Barry at ampmaker has a switch in his 18w to make it single ended which is neat. Interested to see how you get on with the LND verb.

chaliapin wrote: ↑

Fri 02/17/23 2:42 pm

I saw Barry at ampmaker has a switch in his 18w to make it single ended which is neat. Interested to see how you get on with the LND verb.

Me too

re. your schematic, is that drawn correctly? Where is the power tube grid reference? You've eliminated the 1M grid leak and have a cap (0.0047uF) blocking a path to ground through the volume pot. I'd move the bright cap there between the treble pot and volume pot.

Don't ask me how I spotted this .

Pressed_Rat wrote: ↑

Mon 02/27/23 5:11 am

re. your schematic, is that drawn correctly? Where is the power tube grid reference? You've eliminated the 1M grid leak and have a cap (0.0047uF) blocking a path to ground through the volume pot. I'd move the bright cap there between the treble pot and volume pot.

Don't ask me how I spotted this .

How did you spot this?
You’re absolutely right though. I first had the resistor undefined on the schematic to tweak where it should land in value. But since lifting it from ground really made no difference I didn’t see the point in keeping it… accidentally resulting in no grid reference at all. Nice catch!
Although I’m not keeping the SE character I’m afraid. It’s useless to me… and honestly merely an experiment

What didn't you like about it? Guess you're not adding the reverb then...

chaliapin wrote: ↑

Wed 03/01/23 8:43 am

What didn't you like about it? Guess you're not adding the reverb then...

The reverb is built in. But it’s pretty generic sounding. The volume is too low to be useable… nah… I know how good this amp gets, and this is nowhere near

Ok after tweaking the reverb in sequence of the other changes I unfortunately have to say it ruined a or some components in the reverb circuit.
Nevertheless the amp sounds great sans reverb, with a decent volume too.

But I don’t know when I can deliver a sound clip. My son had a severe snowboarding accident last weekend and lies in a hospital bed next to my work shop

Yikes! I hope he has a fast and full recovery. I'm sure your loud guitar playing will be soothing to him.

Thanks
I just did a clip with volume and gain on 10

rock!!!

https://youtu.be/M7LdE-lZN5c

Sounds great as usual. No criticism intended but for me your playing/ amps mostly sound better without the reverb. Want to work out an SE mod for my 36w if I ever get it working properly. Very sorry about your son, must be very stressful.

Sounds great! Nice choice not giving up on it.

I'm eventually going to do an EL34 SE version. I might do it with a F* style reverb circuit since I'll have the space.

JMPGuitars wrote: ↑

Sat 03/04/23 3:11 pm

Sounds great! Nice choice not giving up on it.

I'm eventually going to do an EL34 SE version. I might do it with a F* style reverb circuit since I'll have the space.

Might beat ya to it
Anyway… this EL34 stays in it. Much better than the 6L6

Bieworm wrote: ↑

Sat 03/04/23 3:34 pm

JMPGuitars wrote: ↑

Sat 03/04/23 3:11 pm

Sounds great! Nice choice not giving up on it.

I'm eventually going to do an EL34 SE version. I might do it with a F* style reverb circuit since I'll have the space.

Might beat ya to it
Anyway… this EL34 stays in it. Much better than the 6L6

You're welcome.

...do it! If I like it, I'll build it also and make some official docs for it.

I’ve built in a full blackface reverb. I think it sounds good, but it’s late to try the amp on decent volume. I hear a nasty buzz… but I will address that later…

Here’s a clip with the BF reverb. This is soooo nice… less drive on this tele though.. but you get the idea

https://youtu.be/GTJ8-E9c5I4

Bieworm wrote: ↑

Mon 03/06/23 3:27 pm

Here’s a clip with the BF reverb. This is soooo nice… less drive on this tele though.. but you get the idea

https://youtu.be/GTJ8-E9c5I4

I dunno what it is, but that tele has a poorly defined low end. How are the pickup heights?