Description

Audio Note, WE-91A, Rega, Ayon
1/20/12 -I built a 300b single ended triode amplifier based on Joe Robert's Western Electric 91A. Used all vintage caps and vintage resistors-Alen Bradley and Ohmite. These vintage parts came from Leeds Radio just a few subway stops from my apartment in Brooklyn. The coupling caps are .1uf V-Cap TFTF. Large motor run oils in the power supply. Sophia Electric 91-05 Opt transformers and Sophia Princess Mesh Tubes. Stancor PT's came from ebay.

3/2012: Replaced the Alps Potentiometer with a Goldpoint 50K stepped attenuator. More clarity and transparency through the entire frequency range.

Still not using a pre amp.

5/12- Replaced the oil capacitor C-3 biasing the 6C6 with a Black Gate.

6/6/12- Finished new chassis

7/12 - Added Rega P3-24 with Power Supply and Exact Cart. Will look at different cart options later

7/12 - Pulled the 24 gauge silver hookup wire used throughout the amp and installed 16 gauge pure copper wire. The 24 gauge wire gave the sound a weightless quality that I did not like.
The 16 gauge has been in for three weeks and I can report that the weight and depth has very pleasingly improved. Vocals have an added pleasing quality. Instruments throughout the entire frequency range have more depth and richness. The low end is more powerful. I can more easily perceive the stage that the players are performing on.

10/12 Pulled C-5 and didn't replace it. Pulling this capacitor has changed the sound of this amp. Clarity and detail throughout but especially in the lows thru the mid range. Much easier to detect decay and the accompanying reverb. Dynamics seem more unconstrained as well. It has decreased gain by around 20% but in my room with the AN-e's it does not matter.

1/2013- Replaced the 1k Allen Bradley 6C6 Cathode resistor with a Vishay TX2575. This resistor is very neutral...almost as though it has no sonic character of its own. Each instrument has its own accurate color and detail but not at the expense of the overall musical message. Took about 100 hours of break in time.

2/16/13--After a month with the TX2757 in the 6C6 cathode position, including bypassing them with Black Gate Caps I decided to pull these resistors. They did not provide the richness and room filling sound that the A-B's and the older AN Tantalum did. A few weeks ago I got two of the most recent production 1k An Tants from the Hi Fi Collective.

These new Tants are more closely akin to the A-B's than to the TX2575's. They are not as sonically accurate or pure as the TX's. But they do fill the room with rich satisfying music like the A-Bs but with more detail and without the extra noise or warmth or whatever it is with the A-B carbon comps. Still running the amp without the 6C6 bypass cap.

2/2013--Built a home brew phono pre amp using the Audio Note M3 schematic.

4/2013-Upgraded to the Rega White belt and Groovetracer Reference subplatter. Excellent sonic improvement.

5/2013- WE91a amp---Replaced the the screen cap (6C6) which was an oil with a 12uf Solen cap. Have about 50 hours on the Solen. Not sure I like it. Makes the amp sound a little cold and forward. Will live with it for a while.

Late 5/2013. The 12uf Solen has broken in and I like it better than the oil that it replaced. Warmth but with plenty of detail.

Mid 7/2013 (Audio Note DIY Phono pre) ---- Added Audio Note Tantalum resistors into the signal path. 7/27/13-took out the .047 and .33uf Solen caps in the signal path of the phono pre and added .047 Vcap TFTF and .33 Audio note copper caps.

8/11/13 (Audio Note DIY Phono pre) After two weeks with the Vcaps and AN copper caps in the phono circuit my vinyl rig is a lot fun to listen to. A more beautiful and open sound than with the Solen caps.

10/12/13 WE91a---
replaced the 15uf oil cap that was biasing the 300b tube with a polarized 22uf Black Gate. Will listen for a while and see if I like it.

11/1/13 WE91a
The Black Gate by itself is still fine.

I cleaned the resistor and Cap leads, tube sockets and tube pins with 99% alcohol. They have been in the cicuit for 2 years and were tarnished and very dirty. Once cleaned much more mid range clarity and cleaner bass.

11/20/13 Added Gold Lion GZ34 Rectifiers. Sound is open and airy. Very nice

12/28/13 Added Emission Labs 300bXLS.

2/17/14- Audio Note Home Brew Phono Pre-Finished new chassis for the Power supply.
Added 8 more Tantalum Resistors (4 per channel) to the Phono circuit. Now the circuit has a few A-B's and 6 Tantalums per channel. Phono pre sounds a lot better than it did with the PRP red resistors.

3/16/14 WE91A. Because the EML300bXLS tubes are so well internally balanced, I was able to remove the Hum pots and still use AC heat. Now the 300b bias is going thru the center tap of the 5volt filament transformer. Without the hum pots, the sound is much freer and alive. I am liking this!

3/31/14-AN Phono Pre. Replaced several more PRP resistors that were on the plate of both the PS and circuit with Mills. Hopefully they will sound better than the PRP's

5/1/14 WE91a. Took out the Allen Bradley grid leak resistors and replaced with Shinkoh Tantalun resistors. took about two weeks to break in.
5/25/14 WE91a. Put the Allen Bradley grid leak resistors back in. The Shinkoh Tants made the amp have a glare that didn't go away even after the resistors were broken in.

Running the Amp at 425V B+ is sounding good with EML 300bXLS and GZ34's.

6/7/14 AN Home Brew Phono Pre-
Took out the last PRP resistors in the circuit and replaced with Allen Bradleys. Very nice change. Now the circuit has a good mix and Tants and Allen Bradleys. There are a few more PRP's in the power supply that I will replace very soon.

6/22/14 AN Home Brew Phono Pre- Took out the last of the PRP resistors in the power supply and replaced with Mills resistors

9/23/14 AN Home Brew Phono Pre - Installed Audio Note Copper Capacitors in the RIAA network. .0028uf and .0082uf in each channel

11/21/14 AN Home Brew Phono Pre - Replaced the six more Allen Bradley resistors (3 per channel) with Takman one watt resistors.

11/28/14 AN Home Brew Phono Pre - Tweeked the voltage in my phono pre. Very good results. Much more open and transparent sound. Orchestral strings sound really nice.

12/6/14 Rega P3-24. I added a Audio Note iQ3 cartridge. Needs about 100 hours of break in.
Rega Exact is a great cartridge but opportunity came up. We'll see which I prefer once the iQ3 is broken in.

12/13/14 WE91a. installed Duelund Copper Cast coupling caps. After two weeks more natural sounding than the V-cap Teflon

1/12/15-Duelund Copper CAST 630v coupler caps have a very natural, emotionally engaging musicality with a very rich and colorful tonal pallet. Keepers for sure!

3/1/15-WE91a - Experimenting with WIMA power supply caps. These are Metallized Polypropylene. C2 in my power supply is a 100uf oil. I have replaced it with a 50uf Wima. I think the 50uf is a better choice as it controls the woofer a bit better.

3/7/15- WE91a - Added new custom built power transformers by Heybour. 250mA. Also added another WIMA cap at C1- its a 15uf.
B+ went from 424 to 450. 375v across the 300b plate. 76mA. With all these changes the amp has better control over the woofer. Punchy bass.

3/25/15 WE91a. Took out the Wima at C1. Made the amp sound harsh. Put it a GE F97 oil.
3/30/15 WE91a. Took out the Solen 12uf Cap on the screen of the 6C6 driver tube and replaced it with a 22uf Black Gate VK cap. The Solen is muddy compared to the Black Gate. I didnt realize how important the cap on the 6C6 screen is to the sound of the amplifier.

4/15/15 WE91a - A friend has lent me four low DCR 2H chokes (two per channel) to try in place of the single 10H Hammond in each channel. PS is now 15uf/1.8H/15uf/2h/50uf. Amp sounds faster and more nimble. Nice.

5/14/15 WE91a. I have bypassed the Wima Cap at C2 in the power supply with four very low value film caps. Too soon to draw any conclusions about sound.
5/31/15 WE91a. New production Audio Note 50uf Kaisei Power supply capacitors have arrived and after a week of burning them in, I have installed them in place of the Wima 50uf and all of those bypass film caps. will see which I like better in a couple of weeks.

6/13/15 WE91a. The New production Audio Note 50uf Kaisei Power supply capacitors have been in my power supply for two weeks - about 100 hours or so of playing time. They have a purity, and a crystal clear clarity that no other cap in the power supply has had. I am going to replace the rest of the PS oils with these to see what happens. Maybe it will be too much- who knows. They dont have too much of a sonic signature. They just sound very free and open so adding a few more may be ok. If not I can put an oil back in.

7/10/15-WE91a. Installed Audio Note Ultra Hi B output transformers today. Will need a few weeks to come around.
9/1/15 - WE91a. The Audio Note Transformers and great with excellent depth and coherence. Added copper shrouds. 
9/25/15 -Western Electric Speaker wire and interconnects. I like the speaker wire better than my Audio Note Lexus copper. More direct. They make the Lexus cable sound soft around the edges and diffuse. The WE Interconnects are very good too. But still learning about there sound.
10/11/15 - WE91a. Took out the 6C6 driver tubes and installed C3m drivers. 

11/28/15 - WE91a. Added Regulation to the Screen of the C3m driver tubes. K&K CCS board and an OD3 glow tube that is puts out 150volts. The C3m driver tube and regulation is an excellent driver of a 300b output tube. Very fast  and dynamic with lots of detail and musicality. I am very happy with the sound of this amp.  Probably not making any more changes for quite a while.

1/1/16 - WE91a I still notice a bit of extra weight in the lower mids so I replaced the last oil cap in the power supply (c-1) with an Audio Note Kaisei 50uf cap.

2/1/16 -WE91a. After adding additional Audio Note Kaisei capacitor to the power supply, the voicing of this amplifier is complete. The power supply is 50uf/5h 30ohm choke/ 50uf and it sounds dynamic fast and clean. With all Kaisei caps in the power supply the lower mids are now more open and that weight I mentioned above is gone. Will rebuild the amp onto a new piece of wood and hide all of the hi voltage parts underneath. Will post pics of the new build as it progresses.

3/10/2016 - WE91a.  New Chassis is finished. The new build features and extremely short signal path and a copper box known as a "faraday cage" which isolates the audio circuit from RF/AC, Cell phones, and other nasty's. The goal here is to eliminate the grid stopping resistors that are usually necessary on many tube grids. In a SET amplifier any extra part effects the sound especially a resistor in series with the grid. They are usually necessary on the C3m grid as well. Without a grid stopper the C3m tube can squeal and make all sorts of other very harmful noises but with my new chassis implementation I have not needed a grid stopper.  If the C3m tubes continue to behave it would be a major step forward. The sound of the amp without a grid stopper is more open free and natural.

4/2/16 - Audio M3 Phono Pre- I had some copper left over from my amp build so I made a 8x6x2 copper box and put the phono circuit inside. Pics added.

5/16- Bought Kondo KSL-LP silver interconnects and am using them with Audio Note Lexus Bi Wire copper speaker cables. After trying various IC's like homebrew WE-16g and Ocellia silver reference and various Speaker cables like WE-16g and 10g and Kondo KSL-SPz, the Kondo KSL-LP silver interconnects with Audio Note Lexus Bi Wire copper speaker cables really bring something special to the table at least to my ears system and room.

9/20/16 Ayon CD07 - put in NOS Raytheon 5687 tubes and after a week of break in they sound tremendous. Transparent mids fast and clean lows and clean extended highs. Better than any tube thus far.

10/2016  WE91a - I removed the 91k bleeder resistor from the last cap in the power supply. I can't believe how much more open, free and transparent the sound is. It's like that bleeder had clamped down on PS and now without it there is more energy coming into the room. Any tonal warmth that had been left in this amp is now gone.

11/2016 WE91a - with the bleeder resistor removed I noticed a tinniness in they high frequencies so I removed the GE 12gauge wire from both the power supply b+ and ground and replaced it with vintage WE 16gauge wire and that tinniness is now completely gone. The WE vintage wire sounds very good just as others have reported.

1/2018 -WE91a. Replaced the Goldpoint 50k stepped attenuator with a Seiden Shunt stepped attenuator loaded with Audio Note tantalum resistors. Its been in for about a month and I am shocked at the change in sound. Extended highs and lows and more lively mids. Huge step up. The highs and mids are so open and beautiful. Powerful bass. A very worthwhile change.

3/2020- WE91a.  Over the past year and one half, experimented with a .22UF Russian vintage cap in the coupling position in place of a duelund .1uf copper cap after growing tired of the  accurate and analytical presentation of the Duelund. The Russian cap did not do anything that I liked even after a year of listening. It was kinda like all the instruments turned the color of grey. I’ve had some Audio Note copper .47uf caps sitting around for a few years so put them in around the first of 2020 so they now have three months on them. 

The AN copper .47uf coupling caps after a two month an up and down ride stopped changing about a month ago. So I’ve been listening for a solid month after they finally settled in.  

I perceive no less detail with them compared to the duelunds but the detail is integrated into a more musical and three dimensional presentation. There are real instruments playing in front of me. Much more texture and dimension. There may be just a bit of glue tying everything together but even with the glue, there is individual instrumental color and tone in spades. A bit more overall warmth and richness.  Keeping in mind that my system has AUDIO NOTE output transformers, speakers, speaker cables, resistors and capacitors, kondo interconnects and an AN IQ lll Cartridge. So I would have thought adding an Audio Note coupling cap would have been to much, but it actually brought everything together in a very nice way.

 I think they might be too much of a good thing in a system that already fills out a three dimensional space but for me they add something lovely and musical that was missing. This reminds me that there is no such thing as the best capacitor or best anything else....

Read more...

Room Details

Dimensions: 25’ × 12’  Medium
Ceiling: 9’


Components Toggle details

    • Audio Note UK Audio Note UK AN-e LX HE
    Fun to listen to speakers that do a nice job with most types of music
    • DIY WE91a
    Very natural sound amp with good pacing. Duelund Copper cast caps. Audio Note Ultra hiB Output Transformers. Very short signal path and power supply wiring.
    • DIY Western Electric WE-91A
    Old breadboard

Comments 326

Showing all comments by tjkurita.

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222222&text=tj
More good thoughts, Jet. Thank you. I had AN coppers in the amp 12 or so years ago. I remember it sounding good. But there were different trannies in there and I think this was before AN was using Mylar so the amp was nothing like it is now. I always attributed any lean sound to the speakers I am using.  Changes in speaker positioning have really resolved a lot of those issues.  I was sitting too close (was 8’ then 9’ and now 10’ away).  I am really happy with the sound now. I might try some coppers in there at some point. I have a tech who is a lot closer than NYC so when I have the chance one day...  I might give some new speaker wire a shot. Starting to get into change for changes sake so I gotta be careful. 

tjkurita

222222&text=tj
Good hearing your thoughts on the duelund vs audio note. I was considering switching out the AN caps in my amp with duelund but your description of the sound from the AN so closely matches my experience that I wonder if the duelund would also have a similar sound. My amp is extremely detailed and the principal effect the AN had for me was to add richness to the detail. I would not want to lose that richness by switching to a different cap. Glad you are out there making these changes on our behalf.

tjkurita

222222&text=tj
Hey JET!!!!   Your system is looking AWESOME!  I love the chassis you built around the amp.  Keep the small fingers and paws from getting in there...  Just checking in to say hello.  I have been completely out of the forums lately.  Just busy and distracted.  But still enjoying my system.  Updates on the way as I bought a home and put the system in an entirely different kind of room.  I hope all is well with you and I still want to swing by to hear it.

tjkurita

222222&text=tj
Digging the new pics, Jet!

tjkurita

222222&text=tj
Hey Jet,

How are those EMLs treating you? Let's hear an update. I am looking into some additional 300B variants. While I LOVE the Takatsuki, I wrote and asked them what the expected life is and they replied a paltry 5000 hrs. This OK, and I have two pairs, but it makes me think what else is out there that does not cost $1500 a set...

Which brings me to the Psvane western electric replica... You mention in your thread that you were using Psvane tubes. They didn't happen to be the WE replica, did they? As I have mentioned before, I liked the WE reissue from the 90's (many do not). I wonder if the Psvane version sounds at all like that one...

I am seriously considering the Psvane replica. Especially because the base is "normal" width (1 3/16") and the chassis of my amp has a hard time accommodating the 1 5/16" bases of the the European and most Chinese 300B.

tjkurita

222222&text=tj
Thanks Jet! I will probably have to go with WE once the new production tubes are released.

tjkurita

222222&text=tj
Hey Jet, Charles, have you found that the base of the EML is the same width as the Sophia? I know that the Takatsuki and Western Electric 300B has a slightly thinner base than the big ceramic bases on the Sophia and JJ tubes. The holes in the chassis of my amp have very tight tolerances for tube bases. TA and WE fit with some extra room, Sophias are a bit tight. If I want to use alternative tubes long term, the thickness of the base is something of a concern for me. I am interested in the EML tubes and I am curious about the size of the base.

tjkurita

222222&text=tj
OH MAN! I wish I could have made it to this meet! I had it all planned out: dividing my time between family obligations that were very important to me and getting over to jetrex's place. The problem started when my stepmother, who is visiting from Japan, and whom I primarily went to NYC to visit, changed her plans and so was unable to spend time Saturday morning. As a result I had to forego my afternoon plans to be with my family.

It sounds like missed a great experience. ISO was unable to describe how good the sound was! WHAT? Awesome. That's what. I wish I was there!

Interestingly, and I will have to elaborate in my thread, we went to see Mussgorsky : Pictures at an Exhibition at Lincoln Center Saturday night. Orchestra level 8th row! The sound was ENORMOUS! Truly an overwhelming experience. I only just got home. Tonight I cannot listen at the kinds of levels I would like. But I am going to spin a few orchestral works after that reality check.

tjkurita

222222&text=tj
Jetrex,

I received the Audionote silver capacitors today! I'll be bringing the amp down this Friday to have Blackie install the caps. The bad news is that I will not be able to bring the amp by your place. I will be going down on Friday 10/18, dropping the amp off, picking it up on Saturday 10/19, and returning to Upstate NY. This probably means I will not have time to hang out. If you guys are available, maybe we can figure something out. I will then return to NYC on 10/25 and stay until Sunday, 10/27. Please let me know your plans. Hopefully we can all get together.

tjkurita

222222&text=tj
Obviously, I am also going to bring my Sennheiser HD 800s if this is going to expand into a headphone meeting. I've got a headphone jack tapped to the output trannies on my amp. I also have a 50WPC Audiosector Patek SE based on the 47 Labs Gaincard... These are all things I can bring. The Audiosector plus Placette RVC is a VERY compact setup.

The only issue I might have is that Jetrex has feline residents and I am SEVERELY allergic. I may have to take repeated breaks.

tjkurita

222222&text=tj
I've got a stepped attenuator with Vishays on my amp, but I also have a Placette passive volume control I can bring. It is extremely easy to tote around.

I will have to move all my gear around anyway to get the caps installed so one more piece will be no problem.

Iso is right, though... I'm not very much interested in hearing my own gear. Mostly I would like a quick lecture on SET circuit design and a walkthrough of Jet's amp. If I could get my ears on those Cardinals I would consider myself very lucky! But I can understand Brett's desire to keep things close to home. Moving around gear is pretty difficult unless necessary.

John.

tjkurita

222222&text=tj
Hey Jetrex! I am planning on a visit this fall, definitely. Here's the thing: I am ordering some Audio Note Silver capacitors to have Blackie install them. I may be able to bring my amp to your place and we can hook it up to your ANs. Granted, the caps will be pretty cold/unbroken, but it might be fun to have a listening session. I can also bring my Takatsuki 300Bs for you to check out. Unfortunately, I need to order the caps direct from AN and then get an appointment with Blackie during a time when he can do a 24hr. turnaround. This might take a little while. Maybe mid-late October, into November. Hopefully there is not a huge rush.

tjkurita

222222&text=tj
Jetrex: I would like to be considered for a roaming membership as my brother and his family of five live in Manhattan. I visit often. In addition, I only moved out of NYC three months ago, so I still consider myself a resident. I wish I could afford a place in NYC large enough to accommodate my system as beautifully as my "house in the country" does. I also wish there were more like minded music lovers out here... I am going to take you up on your offer to check out the system (if even for 15 minutes) when I am in NYC in October.

Right now, I'm off to listen to some Chet, inspired by your recent choice. I will leave you with what I have been listening to lately: Lee Konitz: "Motion."

tjkurita

222222&text=tj
Don't forget Ddriveman, Charles! His system is definitely on my list of "Must Hear." It IS funny how there are different kinds of listeners and systems, but certain people clearly pursue certain signatures. Any of you are always welcome to my place. I'm off the beaten path, but the tubes will be heated up if you ever roll through town.

tjkurita

222222&text=tj
Hey Jetrex. You were kind enough to comment on my system. I should have come over to yours sooner. I LOVE this system you put together. I wish I had the know-how to do a project like this. The way you describe your system: speed, clarity, but with full bodied sound, is similar to how I would describe my amp. Great sound is a great joy.

I would love to hear your system, if even for a baseline understanding of what a system is capable of when going "all out." It seems like you don't need to make any compromises when it comes to stability or user ignorance as you can tune the system inside and out by yourself. To me, this is one of the greatest benefits of DIY.

tjkurita