Diode clippers

General discussion area for tube amps.

Moderators: pompeiisneaks, Colossal

Post Reply
User avatar
Reeltarded
Posts: 10189
Joined: Sat Feb 14, 2009 4:38 am
Location: GA USA

Diode clippers

Post by Reeltarded »

I posted question elsewhere, but this active place has an answer this week. :)

Add clippers. I take anything after 2 gain stages, say a coupler, and insert the network in series with that coupler to ground? That is basically what happens if it's on a master volume, so it seems right.

The part about me not being an electronics genius makes all kinds of things seem right. :)
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
User avatar
Structo
Posts: 15446
Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: Diode clippers

Post by Structo »

huh? :lol:
Tom

Don't let that smoke out!
diagrammatiks
Posts: 558
Joined: Sun Mar 27, 2011 12:28 am

Re: Diode clippers

Post by diagrammatiks »

diode clippers in a tube amp?
User avatar
martin manning
Posts: 14308
Joined: Sun Jul 06, 2008 12:43 am
Location: 39°06' N 84°30' W

Re: Diode clippers

Post by martin manning »

See e.g. Marshall 2550.
User avatar
Reeltarded
Posts: 10189
Joined: Sat Feb 14, 2009 4:38 am
Location: GA USA

Re: Diode clippers

Post by Reeltarded »

diagrammatiks wrote:diode clippers in a tube amp?
Yep. You betcha. Sounds better than clippers in an SS amp!

Thanks Martin!
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
John_P_WI
Posts: 1457
Joined: Wed Aug 15, 2007 4:29 pm
Location: Wisconsin

Re: Diode clippers

Post by John_P_WI »

diagrammatiks wrote:diode clippers in a tube amp?
Yeah, they work great. Ever hear of the "Jose" mod. One of the mods used diodes. Heresy, I know..... Actually many of the California mods used this method, even Nik put them in his Chupalupa.

They can be placed anywhere along the path, after the coupling caps.

There are many different diodes, even transistors etc can be used as zeners. The beauty of the diodes is that it is "noiseless" distortion.

1N4001 will clip the signal to .7v. A resistor can be placed "on top" or the diode or between the diode and ground. The value of the resistor will soften the effect of the diode or round the edges of the square wave. 1 diode will clip one side of the wave. 2 diodes such as the 1n4001, in parallel will clip both sides with their bands oposing. Caps can also be place across the diodes to soften them to be more tube like.

LED's have a higher clipping voltage than the 1n4001s.

Zeners can be used but must be used in series similarly with their bands opposing. Generally the softening resistor will sit on top of the zeners (throw a 25k pot in there and twist to taste). Zeners can also be used individually if you want to asymmetrically clip the wave form. Their avalanche rating can be used to adjust the level of effect.

Transistors - BJT's- can be used too, some guys like the tone of them, I personally have not used them. They will clip around 7v I believe.

Check out this link and clip half way down the page from Dailey:

https://tubeamparchive.com/viewtopic.ph ... hlight=evh

Sounds damn good.....

Good luck.
diagrammatiks
Posts: 558
Joined: Sun Mar 27, 2011 12:28 am

Re: Diode clippers

Post by diagrammatiks »

well it takes all kinds.

look up the jcm900 non slx schematic to see all the different ways you can possibly do it all in one amp.
User avatar
Reeltarded
Posts: 10189
Joined: Sat Feb 14, 2009 4:38 am
Location: GA USA

Re: Diode clippers

Post by Reeltarded »

I'm back!

Here's the deal. The 2550 schematic has all this switching, and a bunch of numbers, and a tremendous parts count in the area I am interested in..

I twisted 2 1n914s together, and did just what I said. Ok, that workee, but that is my straight brite channel, so I moved it to the previous stage's coupler, since that is all about the gain, right? V1a it is.

Yessir!

I need to put this on a switch. I may move it to just before the tone stack. Legato sounds like a waterfall, and staccato feels like the World is ending. The bad thing is the amp loses no volume with it in the driving stage.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
User avatar
renshen1957
Posts: 498
Joined: Fri Feb 20, 2009 8:13 am
Location: So-Cal

Re: Diode clippers

Post by renshen1957 »

Reeltarded wrote:I posted question elsewhere, but this active place has an answer this week. :)

Add clippers. I take anything after 2 gain stages, say a coupler, and insert the network in series with that coupler to ground? That is basically what happens if it's on a master volume, so it seems right.

The part about me not being an electronics genius makes all kinds of things seem right. :)
Hi,

Kevin O'Connor's first volume of The Ultimate Tone explains this at length.
He goes into diode bonding (using resistors).

You can also use LED's, mix Germanium diodes and silicon diodes. Tubes diodes or 12ax7 tubes wired as diodes can be used as in place of solid state diodes. You can also use Transistors wired as Zeners (the Zener effect existed before Zener diodes) in place of Zener diodes.

Regards

Steve
User avatar
Reeltarded
Posts: 10189
Joined: Sat Feb 14, 2009 4:38 am
Location: GA USA

Re: Diode clippers

Post by Reeltarded »

Sounds like key-rap with the zeners. This is a fun hunt!
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Post Reply