Paramount impedance switch

Paully · 10365

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Offline Paully

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on: May 20, 2010, 09:44:53 AM
Would love to see this reposted, thanks PJ!



Offline Paully

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Reply #1 on: May 21, 2010, 01:59:36 AM
I found it on the old board.



Offline Grainger49

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Reply #2 on: May 21, 2010, 02:31:05 AM
Looks like a double pole triple throw selector switch.  I would say wiring a toggle switch would be way too crowded for speaker wires.



Offline AudioDave

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Reply #3 on: May 21, 2010, 08:14:29 AM
I purchased a pair of impedence switches from Antique Electronics that I use in my Parabees.  They are even marked 4, 8, & 16 ohm and work great.  Have them wired up and hidden under the chassis out of site.
Dave



Offline Paul Joppa

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Reply #4 on: May 21, 2010, 09:33:00 AM
Parabee has the Magnequest TFA-2004 output transformer which has single taps and can be switched with a single-pole, three-throw switch. The Paramount upgrade transformer from Magnequest has only two taps, and a single-pole, double-throw switch will do the job.

The stock Paramount output transformer (shown below) has two tapped windings which are wired in various combinations of series and parallel to achieve the impedance changes, and it requires a two-pole switch. In the one that I modded, I used a 4-pole switch (actually a Foreplay input selector switch) with paralleled poles for lower resistance.

Incidentally, the new Stereomour has a slightly difference design, and a pair of DPDT switches is the most efficient method; it can provide 2, 4, 8, or 16 ohm outputs.

Paul Joppa


Offline Grainger49

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Reply #5 on: May 21, 2010, 09:54:40 AM
When a transformer has a single tap for each impedance you can just add additional banana jacks for the additional impedances.  Placing them in a circular pattern where a dual banana plug can be used is also handy.



Offline kip.duff

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Reply #6 on: September 24, 2017, 04:46:58 PM
Parabee has the Magnequest TFA-2004 output transformer which has single taps and can be switched with a single-pole, three-throw switch. The Paramount upgrade transformer from Magnequest has only two taps, and a single-pole, double-throw switch will do the job.

The stock Paramount output transformer (shown below) has two tapped windings which are wired in various combinations of series and parallel to achieve the impedance changes, and it requires a two-pole switch. In the one that I modded, I used a 4-pole switch (actually a Foreplay input selector switch) with paralleled poles for lower resistance.

Incidentally, the new Stereomour has a slightly difference design, and a pair of DPDT switches is the most efficient method; it can provide 2, 4, 8, or 16 ohm outputs.

Paul:  I need to have a selector sw for 4, 8, and 16 Ohms for my Paramount 1.1's.  Just got some Altec A7/828's! (but 16 Ohm)  Can I get a Bottlehead part number- or universal part number so I can buy local?  Or whatever your best current recommendation is to have impedence selection.  I like your idea about 4-pole.(redundancy).  Thanks, Kip....

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Online Paul Birkeland

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Reply #7 on: September 24, 2017, 05:52:29 PM
This should work:
http://www.mouser.com/Search/m_ProductDetail.aspx?CK-Components%2fA40315RNZQ%2f&qs=sGAEpiMZZMvNbjZ2WlReYus8Y6%2fQzAi05bQNaEcIi7A%3d 

The actuator is 1.5" long, but it's plastic, so you can just trim it down.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline kip.duff

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Reply #8 on: September 25, 2017, 04:36:19 PM
Awesome..... :)

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline kip.duff

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Reply #9 on: November 02, 2017, 12:17:54 PM
This worked out really well but took me a while to figure out schematic and placement to keep things neet.  I hope to post some photos and the schematic should anyone else want to try it.

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline kip.duff

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Reply #10 on: November 15, 2017, 05:59:02 AM
I installed the speaker impedance switch that Paul Birkeland recommended in this thread because I have speakers with differing impedances.  Took a while to figure correct location and schematic.  I'm attaching a picture of the finished install and a PDF I made giving details and pictures of the install.

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.