Comments on: 5 watt SLO

By: Dan

Dan — Fri, 03 Feb 2012 23:45:59 +0000

Could you help me build one of these?

By: Jaime

Jaime — Sat, 12 Nov 2011 04:24:33 +0000

Hey when you move on to something else can I buy it from you :0)

By: Jo

Jo — Mon, 03 Oct 2011 15:56:45 +0000

Hi there,

This may not be at all anything that you can help with but I work for a climate change charity and we’re looking to do something around making/listening/recording music using only 5 watts. We’re only in the research stage at the moment but I just stumbled across your site and you sound like you’re a man that knows a thing or two about music and electricity!!

Is there any chance you can give us some advice? Does this even sound like something that is possible?!

Anything you can tell us would be massively appreciated.

Many thanks, Jo

By: Bancika

Bancika — Thu, 07 Oct 2010 09:41:51 +0000

Yes, preamp is 100% stock. I changed the PI a bit to reduce the output. Also, I made a separate power supply for the poweramp because it can’t take more than 250V. I was stupid not to draw schematic back then because I can’t remember component value, but I’ll check.

By: Cris

Cris — Thu, 07 Oct 2010 00:45:31 +0000

Hi,
5 watt slo. That great. The 100 watt and 50 watt are bleeding my ears. I never mod slo before.
So, you basically use the stock preamp, then just power down the output stage?
In this case, you get 5 watt from AX84.com ‘s power supply style?
AX84.com share the schem and layout. Whict power supply that you use?
Is this one, “5W_SE: AX84 5W Single-Ended Poweramp Files”?
I’m not sure, so I ask you about this, sorry. ^^^

So if basically use the stock preamp, then just power down the output stage. The 5 watt PS design can be done to other amp design?

Thank’s
Cris

By: Bancika

Bancika — Tue, 24 Aug 2010 23:01:34 +0000

Hi mate. I don’t have the schematic but there’s not much to it: I used bias circuit from AX84.com push-pull amps (they are all the same). PI is long tail but I wanted to reduce the output to suit smaller power tubes. Plate resistors are split into two in roughly 2:1 ratio (68K+33K and 56K+28K) with smaller resistor facing the plate and coupling cap is connected between them. That should reduce the output by 1/3. Similar could be achieved by swapping the tube to 12AY7, 12AT7 or even 12AU7.
I believe that grid reference resistors on EL91 are 220K but not 100% sure. I’ll need to draw the schem once, there were quite a few questions like these

Let me know if you need anything else.

Cheers,
Bane

By: David

David — Tue, 24 Aug 2010 20:37:41 +0000

Bancika, I’m planning to build an amp with el91 in push pull with 250V on the plates. can you share your schematic for the PA. Thanks

By: Rev. D.

Rev. D. — Thu, 01 Jul 2010 06:48:55 +0000

Just was going through the old post on Amp Garage and saw your link. Wow man what can I say even though SLO’s are not my thing (more a old blues guy) I just had to give my regards for a fantastic sounding amp. As I say not the style I play but I know what that Genre requires and to think your getting all that girth with 5 watts is incredible. I’ve built quite a few amps but I’m nowhere near as skilled as you are. I did recently pickup some ef184 tubes which I’ll do something with probably high gain, even though I don’t play metal, something along the lines of a EVH type amp would be cool just to stretch my chops into something different. Anyway, just wanted to say job well done.

Regards,

Don

By: Bancika

Bancika — Wed, 19 May 2010 15:04:15 +0000

I forwarded your message to their admins…will let you know

By: Angelo

Angelo — Wed, 19 May 2010 13:54:53 +0000

Nice amp – sounds great.

Has anyone tried to register on the SLOclone forum – if you click on register and agree to their terms it doesnt do anything. Anyone know how to get a hold of the administrator? I cant find an email address or contact info.

Thanks