Paramount Transformer Upgrade II

Gerry E. · 9472

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Offline Doc B.

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Reply #15 on: August 28, 2012, 04:53:41 PM
The set of transformers and plate chokes that Mike sells is for a pair of monoblocks. And BTW I'm not sure where the term "irons" came from, but when we started talking about big ol' transformers in single ended tube amps the slang was "iron" - singular - as in Heavy Iron. My hunch is that some well meaning folks from Asia may have confused the pluralization when they posted on the internet - a common mistake going from a language that makes it all easy by saying "one man, ten man" to English, the most rehashed, complex, constantly evolving crazy language there is. Woman = Wu-mun, Women = Wi-min! Having said that, society dictates what the current terminology may be. Perhaps my perspective is anachronistic.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Brillo

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Reply #16 on: January 25, 2015, 01:03:53 PM
... the BH-5 OPTs that I received only have two output taps.  It looks like they are labeled 9(?) and 16 ohms.  We used the 9 ohm tap for my 8-ohm speakers.                       

I have my 300B Paramounts similarly wired, to the 9 ohm tap.  What, if anything, could/should be done to run 4 ohm speakers, or is this impedance mismatch to be avoided completely?

Chris


Offline Paul Birkeland

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Reply #17 on: January 25, 2015, 01:05:21 PM
  What, if anything, could/should be done to run 4 ohm speakers
Pop the stock transformers back in and wire for 4 Ohms.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Brillo

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Reply #18 on: January 25, 2015, 01:07:48 PM
Pop the stock transformers back in and wire for 4 Ohms.

-PB

Ah, man.

Chris


Offline Paul Birkeland

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Reply #19 on: January 25, 2015, 01:16:52 PM
You can leave the MQ plate chokes in, however, a little extra inductance will certainly work well with either the BH transformers or the MQ transformers.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Brillo

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Reply #20 on: January 25, 2015, 03:44:50 PM
A plate choke with 70mA+ and 30H-40H (or more)?  Do I have that right? 

Chris


Offline Paul Birkeland

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Reply #21 on: January 25, 2015, 04:19:46 PM
Yes, the 300B design center is 70mA, and you want as much inductance as you can fit. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Joppa

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Reply #22 on: January 25, 2015, 06:09:46 PM
The stock choke is about 24 henries, for what it's worth.

Paul Joppa


Offline braubeat

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Reply #23 on: January 26, 2015, 05:45:04 AM
There is always the BAC 80 (80ma) which is huge. From Magnequest. This has wire leads.
Also I ran across this the other day
http://vinylsavor.blogspot.com/2011/12/new-plate-chokes-from-lundahl.html  No wire leads but I think you can buy cases for them.

Michael