Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › WOO Audio 3+ experience
New Posts  All Forums:Forum Nav:

WOO Audio 3+ experience

post #1 of 190
Thread Starter 
The following thread is created to let everybody participate in the process of setting up and optimizing my new bedside headphone setup using a Woo Audio 3+. The hope is that this might be helpful to some fellow headfiers as it may be to myself as a headphone newbie since I would like to ask questions along the way. Comments are also very much appreciated. I intend to post my experiences as they occur in time and I hope it is not too much boring. The numbering of days is not in sucession, there may be some more days be elapsed between two entries.

Listening background: The list of what I do not listen to is most probably shorter: I do not favour Hardrock, Hiphop, Pop (the mass-produced ones), Metal etc. - maybe you get the picture. I favour Jazz, Folk, World Music and in particular guitar, since I am a guitarist myself. My favourite musicians include Pat Metheny and Pierre Bensusan, Leonardo Amuedo etc. In my collection of appr. 1400 CDs, audiophile recordings are common. I do own several playback systems with one of those really reasonably sounding . I am into highend for more than 25 years (back in the 80's Apogee Duetta with Krell KSA100) but a newbie to headphone reproduction.


Reporting day 1: Arrival of the WA3+ and first experience

The WA3+ came in a neat small package, well packed with tubes separately in carton. Everything was undamaged. I unpacked the amp in the morning and let any condensed water dry out over the day.
In the evening - after installing the tubes - I set it up as follows: Standard wall outlet 230V 50Hz <-> Standard power cable <-> WA3+ <-> Moon Audio Silver Dragon Cable <-> Sennheiser 650. Source was a Yamaha DVD S2700 (plays all formats from SACD over DVD-Audio, DVD 96K, CD, CD-R mp3 etc. - actually really everything exept Blue-Ray) connected via Fastaudio Starline interconnects 80cm to the WA3+. Initial power for the source was standard wall outlet via a standard cheap power strip and standard power cable.

Trying a CD without warming everything up first did not floor me at all. In fact the first impression was much worse than using directly the headphone jack of my old Denon DVD5000. However that did not alarm me too much for I did experience this first impression effect already with other audio equipment I own and of course everything needs a break in and of course a warm up period.

More alarming was a faint background hum that did occur irrespective of the volume setting. But as the effect was quite small I continued listening. After about 3 hours of operation and playing a SACD (Stockfish records sampler "Closer to the music" - this is a highly recommended one !), the sound became much more refined. I would describe it as having a big "soundstage" (if one can talk about this in relation to a headphone) and having a real high end resolution, sound on the lean side - lacking probably a bit overall warmth but not missing defined bass. Actually quite nice for the first day - exept for the (slight but annoying) hum of course.

The unit does not hum mechanically by the way - in this regard it is dead quiet ! This is a very nice amp.
LL

Gear mentioned in this thread:

post #2 of 190
Thread Starter 
Reporting day 2: Tracking down the hum

Remove input source -> Hum -> disconnecting everything else from the power strip -> Hum -> changing Headphone cables and Headphones -> Hum -> Change to other power circuit in house -> Hum -> Clean tube pins -> Hum -> feeding the WA3+ via a PS Audio Power Plant 300 with pure 220V sinewave while altering power frequency and voltage -> Hum altering in pitch together with the frequency -> exchanging the stock rectifier tube 6AS7GA with a Cetron 7236 (which I did order before the WA3+ did arrive ;-)) -> Hum reduced to a much lower - acceptable - level (and I am REALLY sensitve to this kind of thing) . I skipped all other phantasies of what to do next and reinstalled the setting in the original place.

Listening to the same SACD as the day before I thought I was experiencing less resolution and a more smoother sound with the 7236, I actually did not like it as on the day before. But I do know that the listening experience is also varying according to ones own state and I was tired this evening. However, I then waited two hours to let it warm up and burn in further. After that it appeared to me that some of the magic was restored - especially on the bass side - deep, colourful and defined. A high end bass reproduction.

Reporting day 3: Optimizing the power situation a bit

Burn in time so far: 21 hours (approx. 50h for the Senns)

I exchanged the power cord of the WA3+ with a self made one with 3 X 1.5 square mm cross sections and with internal connections further optimized by soldering in the wires in addition to using only the screws, it has an optimized short length now and is going directly into a wall outlet.

It appears to me that the sound reproduction is further improved. I could not yet get a rubber connector with only 2 poles to go into my Yamaha source, once I will get one I would make me a new power cable for the source as well. The source is directly connected to the wall, but into a different outlet (on the same home power circuit).

I asked Jack about the 6AS7GA producing hum, too, but did not yet receive an answer.
post #3 of 190
Hi,

I recently purchased the Woo3+ after making the mistake of viewing these forums.

The original plan was just to "buy some nice headphones". Then I ended up with "some nice headphones" plus a new soundcard and an amp... and tubes are probably next.

Anyway, my Woo3+ is still being built, I expect to get it in 2-3 weeks. So I am very interested in hearing about your initial experiences with it. Thanks for making this thread.
post #4 of 190
MooBin,

Just for your information, the Woo 3+ doesn't use a rectifier tube. It uses an internal solid state bridge rectifier. The 6AS7GA is the output tube for both channels, the 6922's are the driver tubes.
post #5 of 190
My WA3 didn't hum at all with high impedance headphones, but did have a little hum with very low impedance headphones. You got the hum with your Senns, not your Denons, yes?

You might want to try some different 6DJ8's as well as the (excellent) 7236 you have already rolled in.
post #6 of 190
double post
post #7 of 190
Thread Starter 
Quote:
Originally Posted by RyanJH View Post
Hi,

I recently purchased the Woo3+ after making the mistake of viewing these forums.

The original plan was just to "buy some nice headphones". Then I ended up with "some nice headphones" plus a new soundcard and an amp... and tubes are probably next.

Anyway, my Woo3+ is still being built, I expect to get it in 2-3 weeks. So I am very interested in hearing about your initial experiences with it. Thanks for making this thread.
Thats how I got here, too. By "Just purchasing a HD650 because it was sold cheaply" and because my old HD600 is really old (appr. 15 years ? - did they manufacture this headphone already then ? - I dont recall). Now I am stuck and learning but it seems to pay off.

Thanks for liking my idea to post the experiences in sucession - but so far there is nothing new to post. I just ordered two "like new" 6AS7GA from tubeworld. Just to compare a "non-humming one" to the 7236 after a while


So the following is in the program soon:
1. Comparing the Moon Audio Silver Dragon with the Cardas Cable
2. New power cable for my Yamaha (there is a small problem here - the connector to the chassis is really special - hope I can find one somewhere)
3. Further tube rolling of the driver tubes
4. Results from changing back the 7236 with one "like new" 6AS7GA

..to be continued
post #8 of 190
I sure wish the engineer(s) at Woo would use DC on the filaments. With efficient cans, that hum won't go away with tube swaps.
post #9 of 190
Thread Starter 
Quote:
Originally Posted by Skylab View Post
My WA3 didn't hum at all with high impedance headphones, but did have a little hum with very low impedance headphones. You got the hum with your Senns, not your Denons, yes?

You might want to try some different 6DJ8's as well as the (excellent) 7236 you have already rolled in.
Yes, it is with the Senns - I dont own Denon Headphones (but 3 generations of Denon DVD-Players - all three working in different rooms). With the 7236 the hum is practically nonexistent - it was the original 6AS7GA who did it !

Thanks for your comments on the tube rolling ! Knowing that I do now have a 7236 in place - what would you recommend for the driver tubes and why ?
I feel I have a world class bass now, but I think (will be thoroughly tested soon) that the 6AS7GA gave me a bit more refined resolution.

Thanks a lot for sharing your experience !
post #10 of 190
Thread Starter 
Quote:
Originally Posted by atbglenn View Post
MooBin,

Just for your information, the Woo 3+ doesn't use a rectifier tube. It uses an internal solid state bridge rectifier. The 6AS7GA is the output tube for both channels, the 6922's are the driver tubes.
Thanks a lot for this info and sorry for my innocence ! Is it that 6992 is the equivalent of 6DJ8 (the driver tubes) ? Sorry just learning step by step.
post #11 of 190
The 6DJ8 can be used in the Woo3, and is the better choice IMO. I like the JAN-Sylvania 6DJ8 as a "bang-for-the-buck" tube - can be had NOS for $15 each and sounds very good. These are what I use in my Decware CSP-2. Beyond that I'd look for Amperex Bugle Boys, but be prepared to spend much more money for those.
post #12 of 190
Quote:
Originally Posted by audiowize View Post
I sure wish the engineer(s) at Woo would use DC on the filaments. With efficient cans, that hum won't go away with tube swaps.
Definitely... I'm sure it wouldn't be too much more either.
post #13 of 190
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.
post #14 of 190
I have no idea - that's a good question for Jack.
post #15 of 190
Quote:
Originally Posted by audiowize View Post
I sure wish the engineer(s) at Woo would use DC on the filaments. With efficient cans, that hum won't go away with tube swaps.
The more expensive Woos do use DC for the filaments. The WA6 Standard doesn't, but I here no hum no matter what cans I'm using. I even tested Apple ear buds and still no hum. Maybe it's just the nature of the Woo 3 ??
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)

Gear mentioned in this thread:

Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › WOO Audio 3+ experience