[RobertSM]

WA6 Rectifier inquiry: I rotate the rectifiers and drivers on my WA6 1st gen for a change of pace. I have an early 50's RCA 5u4g and an early 50's Ken Rad 5v4g (also manufactured by RCA). I have 2 sets of 6fd7 drivers RCA and Sylvania. My headphones are Drop 6xx (aka HD650s). I listen mainly to jazz. Can anybody with a similar set up compare the sound of the RCA 6v4g to that of either the Brimar or Mullard 5v4g versions? Thank you!

Have you read this rectifier thread? It's long but worth your time. The exact tubes you mentioned are highlighted and described. Check it out.

https://www.head-fi.org/threads/dub...mparison-rectifer-tube-rolling-thread.694525/

 

[UMN]

Have you read this rectifier thread? It's long but worth your time. The exact tubes you mentioned are highlighted and described. Check it out.

https://www.head-fi.org/threads/dub...mparison-rectifer-tube-rolling-thread.694525/

Thank you.

 

[RobertSM]

Happy Wednesday fellow Head-Fiers and Woo Audio lovers.

Here's a picture I took of my WA6-SE gen 1 last night. I was listening to the new Phoebe Bridgers album. I'm reallly digging it! Her beautiful vocals really shine with the Woo tube magic.

 

[cebuboy]

Happy Wednesday fellow Head-Fiers and Woo Audio lovers.

Here's a picture I took of my WA6-SE gen 1 last night. I was listening to the new Phoebe Bridgers album. I'm reallly digging it! Her beautiful vocals really shine with the Woo tube magic.

is it me or the tubes look tilted?

 

[RobertSM]

is it me or the tubes look tilted?

Lol.

Good eye. I sent Mike from Woo Audio this same picture and he said the exact same thing. I've corrected them since. But you're right, they weren't seated upright as they should be.

 

[guitargonaut]

Had a WA3 back in 2014 but sold it - enjoyed the amp but never was blown away by it. Been using a Vinyl Flat Can Opener with a Parasound Zamp ever since because I felt it worked better with the headphones I owned. Decided to go the tube route again and ordered a WA6 (2nd gen). It arrived today along with a bevy of NOS tubes purchased in anticipation of doing a bit of rolling. Skipped the tubes that came with the amp and plugged a RCA 5V4 into the amp mainly because the shape looks really neat then a couple of RCA 13FD7s because they are supposed to be the higher output tubes of the assortment ordered.

I have a pair of Beyerdynamic T90s and a pair of Denon AH-D5000s along with a collection of lesser headphones but the T90s and the D5000s are my main headphones.

WOW! While I may suffering a case of new owner euphoria I don't remember the WA3 sounding this good - the Can Opener is no comparison either. Kudos to Mr. Wu on an excellent piece of kit. The detail and clarity are incredible and the soundstage impressive. Looking forward to trying all the different tubes that have arrived. Feels good to be back.

Thought I'd follow up on my post from August.

Bought some RCA and Raytheon 13DE7s, some Sylvania and RCA 13DR7s and a pair of RCA 13FD7s - also managed to get my hands on a pair of GE fat bottle 13FD7s.
For rectifiers I found a RCA 5U4GB and 5V4GA along with a JAN/Philips 5AR4. The amp came stock with a Russian 5U3C and a pair of Japanese 13DE7s.

Did a bit of tube rolling over the last 2.5 months.

The RCA 5V4GA is awesome with the RCA 13FD7s when the amp is set on low gain mode. When set to high gain, I experience listeners fatigue within 15 minutes because of the boost in mids.

The JAN/Philips 5AR4 paired with the GE fat bottles just sounds delicious regardless of the gain setting - by far, my most favorite combination. I'm hearing things through my Beyers I've never heard before in songs I've been listening to for 40+ years. I'm talking about amplifier hum, string buzz, foot tapping, etc. LOL!!!

I can't say that I found any really bad combinations. Like with my guitar amps - the different combinations are similar to a subtle tone circuit. I was amazed at how much of a difference some tubes could make though. I also discovered just how enjoyable my Denons can be at low volume. Kudos Mr. Wu - I'm impressed.

 

[Mr.Sneis]

I scooped up a second hand 6se v1 and out the box the Sophia 274b it came with blew up in the most insane fashion. The tube seemed to have taken out the power LED and the fuse, swapped the fuse and was back in business.

I used the alternate rectifier tube provided, a marconi 5u4g and the amp worked, though the led was then dead. I sent the amp back to woo to get checked out for a peace of mind and replace the LED, cost me about $150 all in.

Got it back this week and all was fine for the first few days. Today I come home after a long week at work and power up to find the led is once again dead, no magic smoke or blown tube this time, just no led.

Amp still works and makes great music but this is definitely not fun to deal with. Sent another email to Woo for now... anyone here have any ideas or experiences like this?

Don't get me started on the seller. Apparently I am just "harassing" the guy now, he wasn't very helpful and seems I am the problem. Go figure. Not much to say other than I've been doing this hobby a long time and harassing someone is about the last thing I'd expect to hear from a buyer or seller, that and I've had tube gear of all kinds in and out for over a decade!

 

[BobG55]

I scooped up a second hand 6se v1 and out the box the Sophia 274b it came with blew up in the most insane fashion. The tube seemed to have taken out the power LED and the fuse, swapped the fuse and was back in business.

I used the alternate rectifier tube provided, a marconi 5u4g and the amp worked, though the led was then dead. I sent the amp back to woo to get checked out for a peace of mind and replace the LED, cost me about $150 all in.

Got it back this week and all was fine for the first few days. Today I come home after a long week at work and power up to find the led is once again dead, no magic smoke or blown tube this time, just no led.

Amp still works and makes great music but this is definitely not fun to deal with. Sent another email to Woo for now... anyone here have any ideas or experiences like this?

Don't get me started on the seller. Apparently I am just "harassing" the guy now, he wasn't very helpful and seems I am the problem. Go figure. Not much to say other than I've been doing this hobby a long time and harassing someone is about the last thing I'd expect to hear from a buyer or seller, that and I've had tube gear of all kinds in and out for over a decade!

That’s a bummer. I own a WA6-SE 2nd gen. & haven’t had any experience like yours. From what I’ve read you sent your amp to Woo so they could check out if there was any additional damage caused by the rectifier and fuse incident. So did you hear back from Woo Audio & did they tell you if they checked out your amp thoroughly aside from replacing the LED ? I’m curious to know how they‘d explain the LED burning out again.

As for your problems with the seller it sounds similar to a couple of experiences I went through also. eBay/ PayPal never seem to take the buyer’s side/ part from my personal experience. That’s a very frustrating situation, so I hear you. Hope the link helps.

 

[RobertSM]

@BobG55-

How are you liking the matched set of tubes you bought from Woo Audio? I know they charge alot, but I'm hoping they have worked out for you. Depending on how much listening time you have had, I'd think they should be burned in by now. Anyway, please share your thoughts and happy listening.

 

[haasaaroni]

Hey y'all! I'm brand spaking new to the world of Woo Audio, just got a WA6 SE Gen 1, and I wanted to ask a rookie question: is it just me, or are almost all of the recommended tubes for this amp either unavaibale or crazy expensive? I can't find matched pairs 6EW7's or 6FD7's anywhere except on Woo Audio's website, and hunting for vintage NOS tubes gets dangerously pricey. Especially for the rectifier.

Are NOS tubes just hard to find in general in matched pairs? Or are stocks just drying up for the 1st gen of this amp? Right now I'm using some 70's Sylvania 6DE7's and the preferred series 274B from TheTubeStore.com, but would really love a more "tubey" sound. Any thoughts?

 

[RobertSM]

Hey y'all! I'm brand spaking new to the world of Woo Audio, just got a WA6 SE Gen 1, and I wanted to ask a rookie question: is it just me, or are almost all of the recommended tubes for this amp either unavaibale or crazy expensive? I can't find matched pairs 6EW7's or 6FD7's anywhere except on Woo Audio's website, and hunting for vintage NOS tubes gets dangerously pricey. Especially for the rectifier.

Are NOS tubes just hard to find in general in matched pairs? Or are stocks just drying up for the 1st gen of this amp? Right now I'm using some 70's Sylvania 6DE7's and the preferred series 274B from TheTubeStore.com, but would really love a more "tubey" sound. Any thoughts?

Congratulations on the WA6-SE gen 1. I have the same amp. With the right tubes it can be really something special.

In regards to your questions...

1. You're absolutely right. Tube stocks of high quality NOS tubes are slowly drying up. They are available but you'll usually have to set aside more of a budget.

2. On the WA6-SE gen 1 you can really achieve more of the tubey sound you seek by rolling the rectifier. It sounds like you and I have similar taste in sound signatures. I've rolled at least 8-10 different rectifiers in the WA6-SE and in my opinion the rectifier that gave me the most tubey sound without being rolled off on the top and bottom frequencies has been the GEC/Osram U52. This is in the 5U4G family. It's considered to be a quintessential example of the classic British Hi-Fi sound. It's got an excellent organic mid range and does absolutely amazing things to vocals. It has a beautiful holographic 3-D soundstage and adds that warmth you seek. The real issue with these tubes is price. They are expensive! You can find true NOS examples for between $400-$650.00. Very expensive but these really one of the holy grail tubes. Some of the other British rectifiers will in part, get you to the level of the U52 but not totally. Some of the Brimar rectifiers in the 5U4G family are very good. Maybe not to the level of the U52 but still very good. These tubes will also come with a more reasonable price. So this is always something to consider.

I recommend reading this thread on rectifiers. I've tried most on this list and agree with almost every point made. I personally didn't like the Western Electric that is highlighted here as the best in the 5U4G family. My thoughts on the Western Electric were that the top end was too bright for my taste. But other than that I think this list is spot on.

https://www.head-fi.org/threads/dub...mparison-rectifer-tube-rolling-thread.694525/

In terms of the 6DE7'S...I'd actually recommend going with the Toshiba 6DE7's that Woo Audio sells. They are also very pricey but really the best of the best. I have a great deal of respect for the extensive screening that Woo Audio does in selecting the NOS tubes that they sell. They go through hundreds of tubes to weed out the underperforming tubes. When you buy a matched pair they are within very tight tolerances. You can actually hear the quality. So again for the 6DE7's I'd absolutely go with Woo Audio.

Anyway hope this helps. Let us know what you decide. Happy listening!

 

[haasaaroni]

Congratulations on the WA6-SE gen 1. I have the same amp. With the right tubes it can be really something special.

In regards to your questions...

1. You're absolutely right. Tube stocks of high quality NOS tubes are slowly drying up. They are available but you'll usually have to set aside more of a budget.

2. On the WA6-SE gen 1 you can really achieve more of the tubey sound you seek by rolling the rectifier. It sounds like you and I have similar taste in sound signatures. I've rolled at least 8-10 different rectifiers in the WA6-SE and in my opinion the rectifier that gave me the most tubey sound without being rolled off on the top and bottom frequencies has been the GEC/Osram U52. This is in the 5U4G family. It's considered to be a quintessential example of the classic British Hi-Fi sound. It's got an excellent organic mid range and does absolutely amazing things to vocals. It has a beautiful holographic 3-D soundstage and adds that warmth you seek. The real issue with these tubes is price. They are expensive! You can find true NOS examples for between $400-$650.00. Very expensive but these really one of the holy grail tubes. Some of the other British rectifiers will in part, get you to the level of the U52 but not totally. Some of the Brimar rectifiers in the 5U4G family are very good. Maybe not to the level of the U52 but still very good. These tubes will also come with a more reasonable price. So this is always something to consider.

I recommend reading this thread on rectifiers. I've tried most on this list and agree with almost every point made. I personally didn't like the Western Electric that is highlighted here as the best in the 5U4G family. But other than that I think this list is spot on.

https://www.head-fi.org/threads/dub...mparison-rectifer-tube-rolling-thread.694525/

In terms of the 6DE7'S...I'd actually recommend going with the Toshiba 6DE7's that Woo Audio sells. They are also very pricey but really the best of the best. I have a great deal of respect for the extensive screening that Woo Audio does in selecting the NOS tubes that they sell. They go through hundreds of tubes to weed out the underperforming tubes. When you buy a matched pair they are within very tight tolerances. You can actually hear the quality. So again for the 6DE7's I'd absolutely go with Woo Audio.

Anyway hope this helps. Let us know what you decide. Happy listening!

This is great. Thanks so much for the info! I was wondering about the Toshiba 6DE7's, and hadn't seen anything about them from others. Glad to know you like them, and that Woo Audio really takes care to find quality tubes.

And yes! I've been referring to that thread you posted about rectifiers to try to find that warmer, richer, more holographic sound. I might try to find a Brimar 5R4GY to start with, before I completely break the bank with something rare and wonderful. Thanks again!

 

[471724]

Hey y'all! I'm brand spaking new to the world of Woo Audio, just got a WA6 SE Gen 1, and I wanted to ask a rookie question: is it just me, or are almost all of the recommended tubes for this amp either unavaibale or crazy expensive? I can't find matched pairs 6EW7's or 6FD7's anywhere except on Woo Audio's website, and hunting for vintage NOS tubes gets dangerously pricey. Especially for the rectifier.

Are NOS tubes just hard to find in general in matched pairs? Or are stocks just drying up for the 1st gen of this amp? Right now I'm using some 70's Sylvania 6DE7's and the preferred series 274B from TheTubeStore.com, but would really love a more "tubey" sound. Any thoughts?

Despite the growing scarcity of NOS tubes, you made a great decision. From both design and sonic standpoints the WA6-SE is outstanding. Design -it's single ended triode and direct coupled (no capacitor) between the input and output, and a tube rectifier pseudo dual power supply. These are all features of the ultimate types of high end audio tube circuits. The only feature not quite so state of the art is the use of a moderate amount of feedback, but this is very much a matter of complex tradeoffs. My preference in input/drive/output is the 6FD7 - for me it is significantly more transparent and extended in the highs. The higher gain is nice for lower sensitivity headphones. I like the indirectly heated 5Z4GY rectifier. In my system it seems clearer than the various directly heated rectifiers like the 5U4 series and 274B.

It does look like Woo Audio is the best current source for the matched pairs of 6FD7s, 6DE7s or 6EW7s. Unfortunately they are pricey. I like the Brimar 5Z4GY available from the British supplier Langrex. I'm currently using a HE1000se, ZMF Verite Closed, Galaxy S4 USB music source, and Yggdrasil DAC with the best cables I can find, Revelation Audio dual conduit USB, Magnan Type Vi RCA interconnect, and ZMF 2000 Copper and Norne Draug 3 headphone cables.

 

[haasaaroni]

Despite the growing scarcity of NOS tubes, you made a great decision. From both design and sonic standpoints the WA6-SE is outstanding. Design -it's single ended triode and direct coupled (no capacitor) between the input and output, and a tube rectifier pseudo dual power supply. These are all features of the ultimate types of high end audio tube circuits. The only feature not quite so state of the art is the use of a moderate amount of feedback, but this is very much a matter of complex tradeoffs. My preference in input/drive/output is the 6FD7 - for me it is significantly more transparent and extended in the highs. The higher gain is nice for lower sensitivity headphones. I like the indirectly heated 5Z4GY rectifier. In my system it seems clearer than the various directly heated rectifiers like the 5U4 series and 274B.

It does look like Woo Audio is the best current source for the matched pairs of 6FD7s, 6DE7s or 6EW7s. Unfortunately they are pricey. I like the Brimar 5Z4GY available from the British supplier Langrex. I'm currently using a HE1000se, ZMF Verite Closed, Galaxy S4 USB music source, and Yggdrasil DAC with the best cables I can find, Revelation Audio dual conduit USB, Magnan Type Vi RCA interconnect, and ZMF 2000 Copper and Norne Draug 3 headphone cables.

Sounds like quite the setup! I read on Dubstep’s review that the Brimar 5Z4GY has that super warm and lush midrange. You don’t find it overly slow or rolled off? It probably helps that the 6FD7’s give it more extension and gain. Sounds like a pretty killer combo. Thanks for the suggestions!

 

[471724]

Sounds like quite the setup! I read on Dubstep’s review that the Brimar 5Z4GY has that super warm and lush midrange. You don’t find it overly slow or rolled off? It probably helps that the 6FD7’s give it more extension and gain. Sounds like a pretty killer combo. Thanks for the suggestions!

As to the rectifier tube I have only evaluated various brands/types in the moderate price range up to $100 or so. With these, the directly heated types such as 5U4 series and 274B were all slightly less clear - a little smeared and muddy compared to the indirectly heated types. I have ascribed this as probably due to the fact that with direct heating the noise on the 5v heater current is directly imposed on the cathode, and is therefore in a sense in the overall amplifier signal path. It may very well be that some of the most expensive and rare directly heated rectifier types are better and perhaps best of all. With my system I haven't noticed an overly "lush" or warm midrange or any slow or rolled off quality with the 5Z4GY.