[grox]

In this thread some head-fiers were saying that the driver tube goes on the left hand side.

Quote:

1. Are the two back sockets the "power tube sockets" and thus by definition the front socket is the driver socket.? YES

But I thought that the driver socket was the one on the RIGHT hand side, on the FAR side of the amp.

I bought my mpx3 from Mikhail in May 2004 and this is what the manual he sent me has to say:

Quote:

Turn the amplifier so the front faces you. Looking from the right to left, input to output, the driver stage is the tube on the far right. You can use any 6SN7 tube in this position. It does not have to be matched. The two tubes on the left are the output tubes. These are better if matched, or at least of the same manufacturer and similar years.

This is my amp (apologies for the terrible pic):


I'm sorry to hear of the trouble people are having with Singlepower at the moment.

My question is: when did the tube placement change? Am I mistaken?

 

[Gollie]

I just received a MPX3 last Monday and I can confirm that the driver tube is the far left (closest to you) tube. The middle tube is your left output and the back tube is your right output.

As far as the position of the tubes changes through the years, I cannot comment on that. Have you sent Mikhail an email?

 

[nikongod]

The tube up in the front has always been the gain/driver tube AFAIK.

I suppose he could have wired some up with the gain tube in the back, but I really doubt it.

With the 3 tubes you have, there should be no difference in sound anyways, they appear internally identical even if the external branding is different. It was not uncommon for a large MFR to build tubes for other companies. This basically meant slapping someone else's branding on the same tube you make all day for yourself.

 

[sacd lover]

Quote:

Originally Posted by nikongod /img/forum/go_quote.gif The tube up in the front has always been the gain/driver tube AFAIK. I suppose he could have wired some up with the gain tube in the back, but I really doubt it. With the 3 tubes you have, there should be no difference in sound anyways, they appear internally identical even if the external branding is different. It was not uncommon for a large MFR to build tubes for other companies. This basically meant slapping someone else's branding on the same tube you make all day for yourself.

Ari, Ari, Ari .... how could you forget about your Supra.

The original toaster MPX3s had the gain tube far right .... followed by the power tubes going right to left in a straight line.

The new MPX3 has the gain tube on the opposite side, far left = actually in center .... with the power tubes following behind in a diagonal line towards the rear of the amp.

 

[Frihed89]

SACD Lover, Those two output tubes. How can they be 6BX7GT...with a metal base and that bottle? What tubes are these? And what SP toaster amp is that, that can run these tubes, whatever they are.

 

[nikongod]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif Ari, Ari, Ari .... how could you forget about your Supra. The original toaster MPX3s had the gain tube far right .... followed by the power tubes going right to left in a straight line.

I had 2 toasterstyle MPX3's too

I was just thinking of the newer cases.

Toasterstyle for the win!
Quote:

Originally Posted by Frihed89 /img/forum/go_quote.gif SACD Lover, Those two output tubes. How can they be 6BX7GT...with a metal base and that bottle? What tubes are these? And what SP toaster amp is that, that can run these tubes, whatever they are.

They are 6as7 (or some variant 6080, etc) the amp was modified to use them, and was one of the prototypes for the extreme if I am not mistaken.

 

[Gollie]

Just to note, my amp has about 100 hours on it now and it sounds amazing. I'm having some DAC issues but I am still in love with my MPX3 SLAM. Those 5687's are some BEASTS!

 

[Rob N]

Those are 6528's?

 

[sacd lover]

Quote:

Originally Posted by Frihed89 /img/forum/go_quote.gif SACD Lover, Those two output tubes. How can they be 6BX7GT...with a metal base and that bottle? What tubes are these? And what SP toaster amp is that, that can run these tubes, whatever they are.

Those are 6528s. This pic is an old one where I put the 6528s in the Supra 392 to amp to see what they would look like .... well before I ever received the Supra-Extreme. These tubes would fry this amp if I turned the amp on. This tube is for the Supra Extreme only.

Supra 392 with 6528s .... a no no.

Here is the Supra 392 tubed with 6BL7GTA .... as designed.

Here is ther Supra-Extreme that can use the 6528 if I choose to ....

 

[Frihed89]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif Those are 6528s. This pic is an old one where I put the 6528s in the Supra 392 to amp to see what they would look like .... well before I ever received the Supra-Extreme. These tubes would fry this amp if I turned the amp on. This tube is for the Supra Extreme only. Supra 392 with 6528s .... a no no.

I'll say. I checked out the specs, but then I did some more digging.

Have you ever heard the HA-2 with these tubes? Would it lower the output impedance of the HA-2?

 

[grox]

Quote:

Originally Posted by nikongod /img/forum/go_quote.gif The tube up in the front has always been the gain/driver tube AFAIK. I suppose he could have wired some up with the gain tube in the back, but I really doubt it. With the 3 tubes you have, there should be no difference in sound anyways, they appear internally identical even if the external branding is different. It was not uncommon for a large MFR to build tubes for other companies. This basically meant slapping someone else's branding on the same tube you make all day for yourself.

That's what's got me worried - I've got 2 hytrons on the left and a sylvania on the right.

I'll email Mikhail and post back when I've got answers. Thanks everyone.

 

[sacd lover]

Quote:

Originally Posted by grox /img/forum/go_quote.gif That's what's got me worried - I've got 2 hytrons on the left and a sylvania on the right. I'll email Mikhail and post back when I've got answers. Thanks everyone.

The picture of the amp you originally included showed the tubes were in the wrong slots. I can guarentee you the gain tube is now the center tube to the far left. The older amps had the gain tube on the far right .... the newer SP amps do not.

 

[grox]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif The picture of the amp you originally included showed the tubes were in the wrong slots. I can guarentee you the gain tube is now the center tube to the far left. The older amps had the gain tube on the far right .... the newer SP amps do not.

I emailed Mikhail and got a prompt and comprehensive reply the same day.

I hope I am allowed to post private correspondence here but this is what he wrote to me:
Quote:

The older MPX3 models in the Stainless steel chassis were made with the input tube from the right and output tubes to the left. The order was changed when we began making the Black Case models. Unless your amplifier was a special build, and there were many of these over the years, then the driver tube is normally near the volume control knob in the center front of the unit.

Thank you everybody!

 

[sacd lover]

Quote:

Originally Posted by Frihed89 /img/forum/go_quote.gif I'll say. I checked out the specs, but then I did some more digging. Have you ever heard the HA-2 with these tubes? Would it lower the output impedance of the HA-2?

HA-2?