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Something New Under the Sun?

45.47.136.180

Posted on June 12, 2021 at 10:12:28
Gerry E.
Audiophile

Posts: 2160
Location: Saratoga Springs, NY
Joined: February 19, 2000
The new Western Electric in Rossville GA has been mentioning their new WE 91E amplifier for at least a couple of years now. No surprise, it's a single-ended 300B amp but with 20 watts output! Yes, single-ended 300B with 20 watts output. It may be closer to being released because they are providing some more details about its circuit design. From the WE website:

"Experience over 20 watts per channel-a first for the 300B. This never before realized level of performance has been achieved with a completely new approach to SE amplifier design. Developed over two years, the 91E's circuitry intelligently steers the parallel feed constant current source (SCCS), allowing the tubes to deliver more than double their previously rated output of 7-8 watts. You've never heard the 300B like this before.

"Our patented steered constant current source always keeps the tubes within their safe operating area. This means full power dissipation without sacrificing tube life."


On the same page as the quote above, under additional features, they also list "Class A3 parallel feed single-ended Triode topology" and "Zero feedback".

My questions are why has nobody thought of this before and (for the amplifier techies out there) given what you know about amplifier design, can this truly sound great given its design? Thanks!

Gerry

 

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A2 will easily get you 12 watts out of a 300B..., posted on June 12, 2021 at 11:00:29
Ivan303
Audiophile

Posts: 43136
Location: Cadiere d'azur FRANCE - Santa Fe, NM
Joined: February 26, 2001
if you need it that bad and its worth drawing grid current for.

Have no idea what A3 might be or why anyone would want that much from a single 300B.

Anyone selling 300Bs for $750 ought to be pushing parallel 300Bs (which I thought he was).







 

RE: Something New Under the Sun?, posted on June 12, 2021 at 13:38:07
Paul Joppa
Industry Professional

Posts: 7123
Location: Seattle, WA
Joined: April 23, 2001
Fortunately for us, John Broskie dug up the patent and analyzed it. Basically it's a dissimilar push-pull with one MOSFET and one triode.

 

RE: Something New Under the Sun?, posted on June 13, 2021 at 08:30:26
deafbykhorns
Audiophile

Posts: 1006
Location: Florida
Joined: October 17, 2003
Did you see the price of the 97A monoblocks?
$1562 per watt isnt too bad for a 5watt amp but 80watts @
ouch!

 

RE: I built nothing but DHT SET until I got hooked on Mahler, posted on June 13, 2021 at 17:14:48
B. Scarpia
Audiophile

Posts: 3030
Location: Near Pisgah Forest
Joined: October 30, 2019
Contributor
  Since:
May 23, 2020
This "Simple 45" circuit of Dan Tucker and Dan Schmalle, breathed on by Steve Brown was the culmination. All the kids thought it was the best they'd ever heard.





Then five years ago I decided I needed more headroom, found and built the Mullard 5-20 Mono-blocks.




I have about $1800 in parts, not $1562 per watt ;-), and remain thrilled with their sound quality whether girl and guitar, Dizzy and Charlie Chan, or The Symphony Of A Thousand. These are the amps I'll be buried with.

There's no virtue in being old,
it just takes a long time

 

Mullard 5-20, posted on June 13, 2021 at 20:14:00
Triode_Kingdom
Audiophile

Posts: 9023
Location: Central Texas
Joined: September 24, 2006
Beautiful amps, but they don't look like the Mullard 5-20 to me. Is that even an EF86 front end? Looks like it might be something else.






--------------------------
Buy Chinese. Bury freedom.

 

RE: I built nothing but DHT SET until I got hooked on Mahler, posted on June 14, 2021 at 04:23:35
deafbykhorns
Audiophile

Posts: 1006
Location: Florida
Joined: October 17, 2003
Nice looking amps
I have 65W SET amps at about $90 a watt and that was using monolith magnetics iron. I think the amps quality is mostly in the OPT.
Looks like you may have some magnequest OPT's?

 

RE: I built nothing but DHT SET until I got hooked on Mahler, posted on June 14, 2021 at 05:25:29
B. Scarpia
Audiophile

Posts: 3030
Location: Near Pisgah Forest
Joined: October 30, 2019
Contributor
  Since:
May 23, 2020
That 45 amp had Magnequest BCP-15 plate chokes and Robin Hood Parafeed OPTs so as a beliver I would have spent for Mike's big Brooklyn P-P OPTs but he was out of action in 2015. On the advice of several of the leading lights at diyaudio that contributed to the 4-60 re-imagining we used Hammond 1650R. With more than a few premium parts used it's difficult to know who did what but the big Hammond OPTs certainly didn't hurt.

Building without NFB the ECC88 became 12AT7 to reduce gain. Triode wiring the EF86 further reduced gain and, along with the Gold Lion outputs, put the sound quality into the heavenly zone.






There's no virtue in being old,
it just takes a long time

 

RE: Something New Under the Sun?, posted on June 14, 2021 at 07:05:43
dave slagle
Manufacturer

Posts: 5291
Location: NYC
Joined: April 27, 2001
Assuming Broskie is correct, I would be interested in seeing the distortion spectra of this amp. I wonder if it is the case where the 300B has the expected SE triode distortion spectra and the mosfet has a "perfectly clean" spectra. Then when summed the resulting spectra is that of a traditional SE amp even though it is PP.

dave

 

RE: I built nothing but DHT SET until I got hooked on Mahler, posted on June 14, 2021 at 09:30:18
deafbykhorns
Audiophile

Posts: 1006
Location: Florida
Joined: October 17, 2003
I went back and read some of the threads in DIY. Are you BillEpstein or tubemack (Florida)? I'm in Florida but get up to the smokeys to mountain bike a couple times a year.
Hammond has some respectable iron, it doesn't necessarily measure as good but they sound great and have some good low end. I used a pair of Hammonds in my 65wpc SET before moving to monolith. I think the bass was a little better with the Hammonds but the monoliths took it to another level.
Getting rid of NFB and triode wiring was a good move.

 

Class A3, posted on June 14, 2021 at 14:31:11
Ralph
Manufacturer

Posts: 4135
Location: Minnesota
Joined: April 24, 2002
was patented by Jack Elliano of Electra Print fame.

Sounds like he found someone to license to!

We auditioned some of his amps using this technique about 7-8 years ago and they worked quite well.

 

Ha!, posted on June 14, 2021 at 15:08:15
Ivan303
Audiophile

Posts: 43136
Location: Cadiere d'azur FRANCE - Santa Fe, NM
Joined: February 26, 2001

Why am I not surprised?



 

RE: Something New Under the Sun?, posted on June 15, 2021 at 11:19:27
deathtube 667
Audiophile

Posts: 2260
Joined: November 25, 2010
"Experience over 20 watts per channel-a first for the 300B. This never before realized level of performance has been achieved with a completely new approach to SE amplifier design. Developed over two years, the 91E's circuitry intelligently steers the parallel feed constant current source (SCCS), allowing the tubes to deliver more than double their previously rated output of 7-8 watts. You've never heard the 300B like this before."

Seems like they built a 300B circuit to compensate for lower efficiency transducers.


DT667

 

OT. When did people start confusing Copyrights with Patents?, posted on June 25, 2021 at 10:55:41
Tre'
Industry Professional

Posts: 15481
Location: So. Cal.
Joined: February 9, 2002



To legally enforce the above the designer of the circuit would have to hold a patent on the circuit. A copyright only protects the image/drawing of a circuit, not the circuit itself.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

It's a scare tactic. :) (nt), posted on June 25, 2021 at 19:49:59
Triode_Kingdom
Audiophile

Posts: 9023
Location: Central Texas
Joined: September 24, 2006
nada aqui







--------------------------
Buy Chinese. Bury freedom.

 

That makes sense. Thanks. (nt), posted on June 25, 2021 at 21:40:38
Tre'
Industry Professional

Posts: 15481
Location: So. Cal.
Joined: February 9, 2002
.
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: OT. When did people start confusing Copyrights with Patents?, posted on July 9, 2021 at 14:40:35
PakProtector
Audiophile

Posts: 12127
Joined: May 14, 2002
And there is a lot of that going around. Threats to sue if something gets copied or examined, or god forbid documented. I recall seeing a lot it on some newsgroup or another regarding some sort of transformer. Some mix of claimed ownership, patents and trademarks...
cheers,
Douglas

Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.

 

RE: OT. When did people start confusing Copyrights with Patents?, posted on July 11, 2021 at 04:44:23
sony6060
Audiophile

Posts: 961
Location: SE MI
Joined: August 8, 2014
A true 20 watt all tube 300B amplifier uses parallel tubes and more likely 16 watts maximum.

 

RE: OT. When did people start confusing Copyrights with Patents?, posted on July 13, 2021 at 05:59:57
kyle
Audiophile

Posts: 1682
Location: London Ontario
Joined: September 29, 1999
I remember that exchange. One side seemed bitter.

 

RE: OT. When did people start confusing Copyrights with Patents?, posted on July 13, 2021 at 14:57:32
Tre'
Industry Professional

Posts: 15481
Location: So. Cal.
Joined: February 9, 2002
Do you have a link?

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: OT. When did people start confusing Copyrights with Patents?, posted on July 14, 2021 at 06:06:59
kyle
Audiophile

Posts: 1682
Location: London Ontario
Joined: September 29, 1999
No link. I do remember the back and forth on the topic. One of the combatants is not really in business now. The other posts here.

 

Thanks. nt, posted on July 14, 2021 at 07:58:15
Tre'
Industry Professional

Posts: 15481
Location: So. Cal.
Joined: February 9, 2002
.
Have Fun and Enjoy the Music
"Still Working the Problem"

 

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