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by **SDS-PAGE** » Mon Mar 17, 2008 4:01 pm

I finished wiring this up today, except for the volume control that I am waiting to receive in the mail. Here is my initial impression (or amazement):
When I heard it play music for the first time, I said to myself, "Finally, this is what I'm talking about!" I think I have finally found a 300B amp that I could fall in love with. JE Labs 300B was alright, so was GSG 300B hybrid, but they weren't anything that I would get excited about.
The WE91A is so SMOOTH. This amp makes listening so effortless. Even with some of tube amps I have, which I think are decent sounding by anyone's standard, I would get hearing fatigue after a few hours. This one could sing the whole day for I care.
I don't know what it is - 5693 pentode drivers, the design, voodoo- whatever it is it's working for me and I am loving it. I really wish some of you here who are thinking about building a 300B amp would give this one a consideration.

by **Slartibartfast** » Mon Mar 17, 2008 4:13 pm

SDS-PAGE wrote:The WE91A is so SMOOTH. This amp makes listening so effortless. Even with some of tube amps I have, which I think are decent sounding by anyone's standard, I would get hearing fatigue after a few hours. This one could sing the whole day for I care.
I don't know what it is - 5693 pentode drivers, the design, voodoo- whatever it is it's working for me and I am loving it. I really wish some of you here who are thinking about building a 300B amp would give this one a consideration.

I am curious. How does one get fatigued listening to good sounding music? I have never experienced it. I have heard from people, "Turn that music off for a while", but they were just casual listeners, not audiophiles or DIYers.

by **SDS-PAGE** » Mon Mar 17, 2008 5:10 pm

I certainly don't have the "golden ears" that can distinguish what parts are used in an amp, but I do get what can be best described as a headache when I listen to something too sharp at certain volume for an extended period of time. It's just a physiological reaction that I get. It's strange, I know.

by **Slartibartfast** » Mon Mar 17, 2008 5:32 pm

SDS-PAGE wrote:I certainly don't have the "golden ears" that can distinguish what parts are used in an amp, but I do get what can be best described as a headache when I listen to something too sharp at certain volume for an extended period of time. It's just a physiological reaction that I get. It's strange, I know.

I too can get tired of a particular style of music after a while and change to something softer, say anything by Dave Brubeck...

"classic" rock can be annoying.

by **ecir38** » Mon Mar 17, 2008 5:43 pm

Congrats, looks like I may have to switch from thinking of building the JE Labs stereo 300B to this. Thanks for your input. How did the cost compare between the two? I imagine if you upgraded the OPT's it would be better.

by **SDS-PAGE** » Mon Mar 17, 2008 6:51 pm

Thanks, I actually stuck with the cheapest alternative for OPTs, which were Hammonds. They were about $100 each. It cost me about $1000 for parts plus shipping (with tubes). There are 6 trannies (two chokes and 4 filament irons) under the chassis, all exceeding required current rating.
Would have cost me more had I powdercoated the chassis. I decided to spend extra on every category of passive components, as I figure it would help the amp last longer. I used a few electrolytics, including bypass caps which were Black Gates. I used a pair of Hovland coupling caps. Used Solens wherever I can. Gold plated binding posts, RCA inputs, and ALPS 100K pot.
It doesn't seem a lot when you look at each part, but they do add up quickly!
Here are pictures showing how all these fit under on chassis:

http://bp1.blogger.com/_i08-ibvZ150/R98Ra8_pigI/AAAAAAAAAv0/se-j07RzoZM/s1600-h/Inside+III.JPG

http://bp2.blogger.com/_i08-ibvZ150/R98RbM_pihI/AAAAAAAAAv8/gJ82BZpN0YQ/s1600-h/Inside+IV.JPG

The shielded input wires and just "hanging out" under I get the ALPS 100K from Hong Kong.

by **TomMcNally** » Tue Mar 18, 2008 6:51 pm

Hey Min -

Do you have a link to the schematic ? I thought you posted
it before, but I couldn't find it. I've never been all that happy
with the sound of my "TimeBandit" 300B (well it sounded great
until some others came along) Maybe I can mod it a little.

... tom

by **SDS-PAGE** » Tue Mar 18, 2008 7:29 pm

Tom,
I just emailed you the schematic. It looks like Raymond Koonce's website is down for now, so a link would be useless. On his website, he mentioned that he didn't like the version that you built either. He modded his blue 300B amp to WE91A. You will notice in his schematic that he paralleled 100/100 uF 500 VDC electrolytics with 50 uF oil caps to keep the hum level down. I didn't find this necessary, but I don't have Klipsch Cornwalls that are over 100 dB/W/m either. Mine runs quiet on my speakers. Good luck. -Min

by **TomMcNally** » Tue Mar 18, 2008 8:03 pm

Got it - thanks !

I should have kept up with his site, I would have seen that.
I was on his site last night, but didn't see any schematics.
I have an odd pulsing hum in my 300B, maybe I can get
rid of it. It's not real bad, but I hear it close to the speakers.
I have a computer in the room that's always on, so it
hides some of the noise of any amp.

You're a real "student of Koontz" now, I see you used those
cheezy "ON - OFF" things on your switches like he does ! Yellow_Light_Colorz_PDT_06

... tom

by **Slartibartfast** » Tue Mar 18, 2008 9:14 pm

TomMcNally wrote:You're a real "student of Koontz" now, I see you used those
cheezy "ON - OFF" things on your switches like he does ! Yellow_Light_Colorz_PDT_06

... tom

They are not cheezy. They are RETRO! Yellow_Light_Colorz_PDT_04

by **SDS-PAGE** » Mon Apr 07, 2008 2:10 pm

I found this for those who like monoblocks:
http://www.angela.com/catalog/how-to/model.91.html

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WE91A - done!

WE91A - done!

Re: WE91A - done!

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