HYBRIDE AMPS

[kees52]

Hi there

I have here a schematic of a hybride with a tube 6C14N high transductance tube with a local current feedback bipolair amp, you can freely use it and simulate for your own, it is maybe interesting to make as the first hybride with bipolairs here.

Maybe a apart section for hybrides can be nice..

schematic can be load in multim 11.

[kees52]

Another file.

these design have a offset tracking opamp so it is not sensitive to drift caused by tube and current feedback, it gives a blockwave of 20 khz without delay or overshoot, (only simulated without load).

I now it is sometimes strange stuff but we have to keep trying to combine already known stuff in the amp world.

[kees52]

This one I have in my home, it is these week changed in what it is now, the sound is open, fast, steep and with a big soundstage and resolution, the used tube in the first stage is a JJ high and low mu valve, ecc832, http://www.jj-electronic.com/pdf/ECC%20832.pdf

In the schematic it is 12ax7 and 12au7 I have not a model for ecc832.

Also a single ecc803 with gyrator is fine sounding, but ears are also very differend.

I can say this design has a very close tube like sound, and is faster and more control over speakers, that was my goal.

But maybe it can stil better, so light your brain.

[kees52]

The penthode however is a EL84, I was forgotten I have also not a model for it and use the 6l6qc

[farjon]

Originally Posted by kees52

Hi there

schematic can be load in multim 11.

It is possible multim 10 versions?

[ingenieus]

Here is a model for the 6BQ5, said to be equivalent to the EL84.

*-----------------------------------------------------------------------
* Filename: 6bq5.inc 23/01/2004 V4
* Simulator: PSpice
* Device type: Power pentode
* Device model: 6BQ5/EL84
*
* Author: Duncan Munro
* Date: 12/5/97
* Copyright: (C)1997-2004 Duncan Amplification
*
*
* V3 [12/10/97]: Screen current limited to prevent screen current
* draw at Vs = 0.
*
* V4 [23/01/04]: LIMIT{x,y,z} statements changed to LIMIT(x,y,z)
*
* The following parameters are not modelled:
*
* (1) Heater
* (2) Grid current is an approximation
*
* Please note that this model is provided "as is" and
* no warranty is provided in respect of its suitability
* for any application.
*
* This model is provided for educational and non-profit use.
*
* Queries via the forum at Duncan's Amp Pages
*
* Pins A Anode
* S Screen
* G Grid
* K Cathode
*
*-----------------------------------------------------------------------

.SUBCKT 6BQ5 A S G K
*
* Calculate contribution to cathode current
*
Eat at 0 VALUE={0.636*ATAN(V(A,K)/15)}
Egs gs 0 VALUE={LIMIT(V(S,K)/19+V(G,K)+V(A,K)/1400,0,1E6)}
Egs2 gs2 0 VALUE={PWRS(V(gs),1.5)}
Ecath cc 0 VALUE={V(gs2)*V(at)}
*
* Calculate anode current
*
Ga A K VALUE={3.2E-3*V(cc)}
*
* Calculate screen current
*
Escrn sc 0 VALUE={V(gs2)*(1.1-V(at))}
Gs S K VALUE={2.0E-3*V(sc)*LIMIT(V(S,K),0,10)/10}
*
* Grid current (approximation - does not model low va/vs)
*
Gg G K VALUE={PWR(LIMIT(V(G,K)+1,0,1E6),1.5)*50E-6}
*
* Capacitances
*
Cg1 G K 10.8p
Cak A K 6.5p
Cg1a G A 0.5p

.ENDS

[kees52]

Most of the time newer files can not load into older programs.

You can try otherwise drawn it over, al the parts are in multisim 10,

[kees52]

These are the blockwaves with this amp, 20Khz.

I have tryed the model posted, but I am not so clever in make a model working with a part in multisim, with I copy from a excisting penthode part, I will go some days praktice with it,.

[kees52]

Well I have studie multisim, now I now how to make models.

I have simulate now EL34 as a mosfet driver and distortion is even lower setting the EL34 on a idle of 40 mA, now I can drive the most big mosfets without loose bandwith.

Multisim is also very buggy, sometimes it will not simulate, or I get database errors, copy the schematic in a new project it work again, versie 11 is more worse then 10
but if it work it is one of the finest and easyest software..

[kees52]

I have perform a spectrum analyzer test, not much harmonics, only a small second one, that is good..

So it is fearly low THD.