Drawback of the Stereomour 45 if the circuit is not optimized for the 45 tube?

[mpent]

Hi,

As the stereomour is not optimized for the 45 tube, what would be the limitations or drawback relative to a circuit that is optimized for the 45...such as the simple 45 circuits that are widely available on line, or perhaps the revered Korneff 45 amp design?

I ask because I am in a quandary of wanting a 45 amp...although I have built a Sex 2.1 and Reduction with their respective upgrades, I did so only with the wonderful step by step instructions included in the kits. I am definitely learning but as I can not read a schematic, I am severely limited. My options as I see it would be to build the stereomour, which I am sure is fantastic...or spend close to 2k or more for a 45 specific circuited amp.  Hence the question...my only hesitation is that I want the optimal experience. I certainly can be ignorant due to my lack of knowledge but would the stereomour be providing the same experience as the latter? Speakers I have are Klipsch Fortes and Heathkit AS 101 which are essentially a clone of the Altec Valencia with what many suggest are better crossovers...altec horn and woofer in a heathkit designed cabinet...

[johnsonad]

The stereomour with a 4k OPT is optimized for the 45, more so than previous amps with a 3k OPT.  The upcoming SR45 circuit that PJ is working on will use the same transformer as the Stereomour. 

[mpent]

What is an SR45...I was just reading the thread about the new production design that may be forthcoming..meaning what does SR stand for?

[johnsonad]

Shunt regulated power supply.

[mpent]

Thanks.  I hope a production run, even if limited, comes to fruition.

[johnsonad]

If it does, it will probably be by schematic only, no manual.  Read PJ's last post to the thread. The point being, you have a great sounding 45 amp in your home already

[mpent]

I was afraid of that...schematic only. Guess we'll see.  Not sure what you mean by the last point?...having a great sounding 45 amp in my home already.

[johnsonad]

Sorry, I thought you had a Stereomour already and didn't pay close enough attention to what you wrote in the first post.

[Paul Birkeland]

As the stereomour is not optimized for the 45 tube, what would be the limitations or drawback relative to a circuit that is optimized for the 45...such as the simple 45 circuits that are widely available on line, or perhaps the revered Korneff 45 amp design?

If you follow the instructions for the 45 version, you have optimized the amp for the 45 tube.

[mpent]

Ok. My mistake. I have misread PJ's previous posts on the matter and interpreted it inaccurately. Thanks for clarifying.

[Paul Birkeland]

Yeah, that was regarding a different amplifier entirely.

In the Stereomour, you just have to leave out 4 resistors during the build (which is mentioned clearly in the manual in each instance), then the voltages and currents are adjusted for optimal operation with the 45.

-PB

[mpent]

Great, my dilemma is solved then. Thanks again.

[johnsonad]

Bottlehead makes it easy

[Paul Joppa]

Of the many versions of the Paramour, the Paramour II did not have an upgrade output transformer of ideal impedance for the 45. That was one of the reasons we developed the OT-2, used in SEX and Stereomour - to have a quality output transformer that would match well with the 45. The current amplifier is designed from the ground up to work optimally with either tube, as long as it is built for that tube.