Something new - 2A3 monoblocks

[Paul Birkeland]

If the circuit is a refinement of the Paramour, Stereomour amps how about MonoAmore ...

The only relation these have to the Stereomour is that they both use 2A3s.  The iron, driver, operating point, DC filament supply, HV supply, etc. are all quite different.

[Deke609]

Cool. Thanks PB.

The Kaiju OT is 3K.  I wouldn't be surprised if the performance wan't optimal trying to reflect 6K.

I've noticed that PJ often specs iron so that it can be configured in multiple ways, and so figured the Kaiju would be no exception and would have at least one other primary impedance besides 3K. 

cheers, Derek

[Paul Birkeland]

I've noticed that PJ often specs iron so that it can be configured in multiple ways, and so figured the Kaiju would be no exception and would have at least one other primary impedance besides 3K. 

That goes back to when we were using the Speco T-7010 in the old Paramour and SEX kit.  It had both 4K and 8K primary taps, but was discontinued rather suddenly.  Its replacement needed to fill both those roles, so that's where that came from.  If you go back and look at the Magnequest upgrade iron available, there was a specific output transformer for the SEX amp and a specific output transformer for the Paramour.

For our recent higher end products, we have stuck with 3K transformers optimized for 3K use.  Some of the older Bottlehead 2A3 amps from the last century did use 2.5K output transformers though.

[Paul Joppa]

As PB indicated, the Kaiju OPT was designed for exactly one impedance. I only played games with the plate choke, to get more inductance at lower current -  i always intended to use the combination with 2A3s, and it has finally come together.

[Deke609]

Had I not already committed to new 70H plate chokes and new OPTs for the SII-45B rebuild, I'd definitely be your first customer. But I'm still interested.  Another question: can the PT-10 support a B+ of approx 500V and 50 mA draw? If not, how close could I get?

cheers and thanks, Derek

[Paul Joppa]

PT-10 is maxed out at about 390 volts,if you are drawing 50mA.

[Deke609]

Many thanks PJ. 

[BrucePoi]

Roughly when will these be available for order? 

[Doc B.]

We are working that out this week and I hope to have an answer soon.

[Deke609]

The amp will come with DC filaments straight away. 

@PB - does it in fact come stock with a DC heater circuit?  I can't spot it in your pics and the "In Depth" description on the purchase page makes no mention of it and states that the amp has a humpot - which would seem superfluous if the output tube is DC heated.

cheers and thanks, Derek

[Paul Birkeland]

Hum pots are still useful with DC heaters.  The DC heater circuit is built above where the meter mounts.  We would have a really tough time getting to a 250uV noise floor without it!

[Deke609]

Cool. Thanks.

We would have a really tough time getting to a 250uV noise floor without it!

Yeah, I guess i should have figured that. 1/4 mV is incredibly low.  Does the 5670 contribute to that low figure?

cheers and thanks, Derek

[Paul Birkeland]

No, the 5670 doesn't contribute measurably to the noise floor, at least not that I am able to measure.

[QueenBottlehead]

I want to give a BIG thank you to kgoss and Raymond P for helping us decide on the name! Love it, love you guys, and love all of your support!

[Deke609]

Will it come wrapped in lace with scented candles?   ... You know, on account of the name and all