[MooBin]

Quote:

I received some new tubes for the Woo3: a 6AS7G RCA and a pair of Amperex ECC88.
 
Unfortunately the hum is still there,

No wonder - the 6AS7G is most likely to hum - as said before. As for the Amperex - these are fine - but I guess best paired with a 7236. However I would suggest to go for a 5998 and pair it with a more firm sounding tube unlike the Amperex (I had Bugle Boys in the shootout and they would do just too much if paired with a 5998). This will give you a balance between sound definition and airyness. Pls just have a look at the extensive evaluation I made earlier in this thread - you would not regret it - if you do pls do not hesitate to complain to me. I wish you get a phantastic sound out of your WA3.
 

 

[realmassy]

Thanks guys for your support
I have a pair of Tung Sol 5998 coming in a few days (they're actually at UK customs), and I really hope they'll be quieter.
I'll probably pair them with the JAN Sylvania.
So far I'm happy with the sound of the Woo, it's just the hum... 

 
The idea that could be something wrong with the amp is killing me: if the noise is there even with the 5998 than I'll have to ship the amp to Mr Woo, though it's a big PITA as I live in UK.

 

[StanT]

My Woo 3 is dead quiet, to the point that I have replaced the video card and fans in my PC because I could hear them between songs. As a desktop system, my Woo was tempermental in regards to cables. Between the PC, printer, and networking components, it was picking up something. Switching to shielded cables, both RCA and power, solved the problem for me.
 
Sorry you are having problems; but you have good advice. Your Woo ought to be absolutely quiet and hum free, don't settle for anything less. It's a very nice amp.

 

[skeptic]

I'll echo what the others have said.  My WA3 also runs silent, and yours should be as well.  Here's hoping the 5998 does the trick!  Both sonically and aesthetically, it is a very beautiful tube, and I prefer it to my Tung Sol 7236 when paired with the amperex 7308s I'm using up front.
 
For the record, I haven't heard any difference in my WA3 based on cabling or amp placement.  Presently, mine is sitting on a wife approved Crate and Barrel shelf, about 8" off the floor, and directly above a budget surge bar with all manner of devices jacked into it, including a gaming PC.  (I'll qualify this by noting that the amp itself is plugged into the high current output of a Belkin Power Conditioner located a few feet away.)  In any event, my guess is that the tubes are causing your hum. 

 

[hodgjy]

I pair the 5998 with JAN Sylvania 6DJ8 and find the combo to be excellent.  Quiet, too.
 
Quote:

Thanks guys for your support
I have a pair of Tung Sol 5998 coming in a few days (they're actually at UK customs), and I really hope they'll be quieter.
I'll probably pair them with the JAN Sylvania.
So far I'm happy with the sound of the Woo, it's just the hum... 

 
The idea that could be something wrong with the amp is killing me: if the noise is there even with the 5998 than I'll have to ship the amp to Mr Woo, though it's a big PITA as I live in UK.

 

[realmassy]

I've replaced the RCA with the stock 6080, and the stock 6922 with the Amperex: yesterday I paired them with the RCA, and thought they were very nosiy and microphonic.
 
But, for my surprise, this is the quietest combination so far!
The amp is not dead silent, but very quiet. The hum is there only between songs or pausing the player. And no microphonics, so I guess the problem was the RCA (or the combination of them).
Those Amperex are not even NOS, so I'm fairly confident the amps is OK. They don't sound great (too bright), but right now I'm not too worried about it.
 
And again, thanks for your suggestions, the Woo community is great
 
EDIT: After 1 1/2 hour the hum is now louder, and more noticeable.

Also the amp itself produces the same noise: it can be heard from 50 cm, and it comes from the front panel

 

[realmassy]

Some good news!
 
I have now the Tung Sol 5998 (thank God I got two of them) replacing the stock 6080...and I'm very very happy to say the amp is now dead silent, even using the stock 6992.
 
And now the excellent news guys
The amps is now bloody brilliant! I'm absolutely thrilled by the sound of it.
During the "Italiana in Algeri" overture (which is part of one of my reference recordings) I had one of those huge goosebumps moments, with sound around my head, not coming from the HD650. The headphones simply disappeared leaving a wide and deep soundstage, very realistic.
 
I have a pair of Sylvania I'll try tonight, but I can't honestly ask for more!

 

[Golden Monkey]

The 5998 with Amperex 6922s is the way to go...I LOVE mine with that combo.  The only noisy tube experience for me was with a TS 5620, which is fairly rare...looks a lot like a 5998 with a 6AS7Gs guts.  Great sounding tube, 5998-like, but very airy and open.  It's a very high gain tube, and extremely microphonic, unfortunately.  I couldn't even touch the volume knob without a "thunk" in my ear...
 
Anyway, I have yet to find any 6080 that doesn't suck, lol.  They all sound dull and flat to me, completely devoid of detail, and lacking any sort of soundstage.  Especially the 6080W* (A, B, or C) which is a military version that is reinforced internally to protect agains shock, vibration, etc.  They make music sound like you are listening to it through a piece of plywood.
 
My favorite combos thus far (I'm still waiting on my Siemens CCa's to arrive from Deutchland) are:
5998/Amperex (US) 6922 (1959 PQ labels) - the best combination of detail, musicality, smooth top end, airiness, imaging, and detail. Magic. Great for live music, rock, blues.
5998/7DJ8 - very lively, warm, and lush sounding.  Again, another great one for live stuff and acoustic performances.
5998/Mullard 6DJ8 - warm, sweet mids, smooth highs, very deep but forward sounding, like you are up close to the performance...seductive and realistic vocals, especially female voices.
7236/Siemens 6922 - bassy, "fast", detailed and spacious.  Almost solid-state sounding...great for techno, electronic, rap and hip hop.
7236/Siemens 7308 - similar to the above combo, but a little more sterile.  Extremely revealing and detailed, but almost to a fault (lol).  Fantastic pinpoint imaging and almost 3D sounding. These are what I use when I want to go deep into the recording.
 
One other thing I'd like to point out...the BIGGEST and best improvement to date for me, beyond any tube rolling is replacing the stock output capacitors with Black Gates. It was an expensive upgrade...I sent it to Jack to do the work, and he charged me $200 for parts and labor, but it was well worth it. Mine are still breaking in, and they take a stupidly long tine to settle down, but my god...it's like a whole new amp.  The soundstage is dramatically wider/deeper, the sense of space and amount of detail is just staggering.  The stock caps are decent, but these really lifted the veil and removed what I considered a slightly congested sound.  Do it...do it NOW!  Lol...
 
I'm almost embarrased to point you guys towards this thread, but I started a tuberolling thread ages ago, when I was just starting out, but: http://www.head-fi.org/forum/thread/375119/woo-3-adventures-in-tuberolling. Some of my observations back then were formed without much reference or experience, but I'm going to update it soon with all new details of tubes I've gotten since then.  Here's a pic of MOST of my tubes:
 

 

[Golden Monkey]

Quote:

Skylab,

would the 7DJ8 work in the WA3+? I'm very impressed with the RCA 7DJ8s I'm using in my WA2. From what I've read, RCAs are actually rebranded Amperex and Mullard, so they're very high quality.

I know this is a really old question, but the answer is yes, the 7DJ8 works just fine in the Woo 3+.  I had asked Jack about it, and he said no, because it requires 7v for the heater, but every reputable tube vendor I know of all said yes, they are a fine substitute for a 6DJ8 (and I DID ask, lol).  I was still curious though, and ordered some anyway (they were just too insanely awesome to pass up...Amplitrex tested, extremely high emission scores, etc.).  My reasoning for thinking they would work is that their operational range is 7v +/- 10%.  7v-10%=.7v=6.3v...just right.  Anyway, I'm happy to report that they sound freaking AWESOME.  These are Valvo labelled Heerlen, Holland Amperex made 1968 A frames, and they sound very musical, lively, and magical. 
 

 

[Golden Monkey]

Oh, here's a sexy shot of my 5998 and Amperex PQs glowing (more in my albums):
 

 

[realmassy]

What a nice collection you have there Golden Monkey!
 
I'm particularly interested in the 5998/Mullard 6DJ8 combo, as I love Mullards on my Earmax, and your words describe perfectly that kind of sound: smooth, liquid and intimate presentation.
I'll probably give them a try.
 
As for the Black Gates caps...well, I'm already regretting them  
Problem is I didn't listen to a Woo amp before, so I didn't know what to expect. Unfortunately shipping back to US is quite expensive.
I may find some one here in UK to help me with that, but I'm too scared to void the warranty.
 

 

[Golden Monkey]

Quote:

What a nice collection you have there Golden Monkey!
 
I'm particularly interested in the 5998/Mullard 6DJ8 combo, as I love Mullards on my Earmax, and your words describe perfectly that kind of sound: smooth, liquid and intimate presentation.
I'll probably give them a try.
 
As for the Black Gates caps...well, I'm already regretting them  
Problem is I didn't listen to a Woo amp before, so I didn't know what to expect. Unfortunately shipping back to US is quite expensive.
I may find some one here in UK to help me with that, but I'm too scared to void the warranty.
 

Thanks!  Yeah, I went a little tube-crazy recently, lol...can't wait for the Siemens CCa's!
 
I really love that Mullard sound as well.  It has such a "vintage" feel, and is just amazing with older recordings.  If you like the signature of them in other amps, I'm sure you'll love them on the Woo!  Paired with the 5998, it's something special...acoustic performances espcially.  The 5998 is so detailed and musical, and has such low end lushness and articulation without being TOO bassy, and the Mullard 6DJ8s have that wonderful warm midrange...*sigh*...
 
As for the caps, that's a good point on the warranty.  Mine's a few years old, so it isn't covered anymore, but that's another reason why I had Jack do it...he does a great job with his amps, and beautiful internal construction, and I wanted to "preserve" that.  BGs were the only options he had beyond the stock caps, but that's fine...those were what I wanted anyway.  There are more affordable options that are easier to find, like Auricaps or the Hovland Musicaps, but size is the main concern, as there's not a whole lot of available space inside the amp.
 

 

[realmassy]

Golden Monkey,
have you ever had the chance to listen to other Woo amps? I'm honestly impressed with the Woo3 and I can't even imagine the Woo2 or the Woo22.
Too bad there are few meetings here in UK.
 
As for the Mullard, do you have any recommendation about labels, factories, years etc etc. I'm a tube-newbie so any help is appreciated!

 

[Golden Monkey]

No, I haven't listened t any others, and I sort of don't want to...it would be expensive for me, I'm sure.

 
Any of the 1960's vintage Mullards would sound great, I'm sure.  I'd look for the halo getter types, The dimple disk getters do not sound as good, I understand, but I haven't heard them myself. The A frame ones came out inthe 70's, but try to stick to 1968 and before.  I've seen them labelled under IEC, Philips, Amperex, and RCA brands, but they'll usually say "Made in the UK" on them, regardless of label.  As for factories, I would look for Blackburn or Mitcham...they turned out a lot of tubes for the military, and are very well made.  The factory code for Blackburn is "B", and Mitcham is "R".  For example, mine are "B6B3" - B (Blackburn), 1966 (last number of the year, so "6"), B (February), third week (3)... Much easier to date/source British tubes than trying to decipher the German ones, that's for sure...

 

[realmassy]

Thanks for your informative reply Golden, much appreciated!