[Jhawkins]

Quote:

 
This must mean something different to you  WA22 is a brute force nothing fancy bridged amp that uses a transformer to sum the output to single ended output.  The Mjolnir is however a piece of art and one of kind, like patent, kind of intelligent.
 
That aside the two amps couldn't sound more different.  And if I wanted the WA22 more laidback, warm full sound... I'd get the B22 for the improved sound stage.  The Mjolnir is all about clarity and dynamics which in comparison is also less deep down low.

 
Does the WA22 brute force design translate into a negative for the sound quality?  

 

[Solude]

No, just not something someone had to invent.  Its a tried and true circuit that's been around for decades.  It just costs too much given the B22 can be had for 900-1500 depending on single ended or balanced.

 

[Jhawkins]

Hi Solude
 
Can you recommend some other headphone amp's that are available based on the same tried and true circuit?
 
I just read about the B22 and it looks rather interesting.  I have been thinking about the BottleHead Crack as a diy project.  I like the idea of diy.

 

[grokit]

Any insight regarding the outputs on the WA22.

Considering they all output the same signal, is it worth upgrading cables for connection's sake? I would guess not.

Thanks for any advice.

I am firmly in the camp of "it depends on the headphone". Some respond better than others to balanced cabling.

 

[grokit]

No, just not something someone had to invent.  Its a tried and true circuit that's been around for decades.  It just costs too much given the B22 can be had for 900-1500 depending on single ended or balanced.

Can't roll tubes for euphonic variety though. It's an excellent way to spend even more $ :veryevil:

 

[Jhawkins]

Quote:

 "it depends on the headphone"

 
For now I've got a pair of hd650, and a set of 325is that I am still on the fence about keeping.   
 
I've been into hi-fi for the past 15 years, but I'm brand new to headphone listening, and turns out I really enjoy the experience.

 

[grokit]

I had a balanced-terminated 325i and didn't think it was worth it. But the HD650 is another story!

 

[Solude]

Let's not confuse balanced drive with balanced cable.  The WA22 outputs L, R and G not L+ L- R+ R-.

 

[grokit]

No confusion, I am talking about how some headphones respond better than others to balanced cabling. With the WA22 if you are using a balanced source you are getting a balanced output:

[COLOR=000000]The WA22 is a fully balanced amp, see diagram below.[/COLOR]




[COLOR=000000]The question here is that this amp is not fully balanced because the "amp with a single ended output stage directly connected to the XLR connectors.” It is not true. In an Output Transformer coupled design, the primary and secondary coils are isolated. Output stage and input stage are not connected and thus no cross-talk whatsoever can happen.[/COLOR]

[COLOR=000000]On the ¼” output, both channels have independent paths, see the black and red wires. If this wiring scheme applies to a Output Transformer Less design, the circuit will become single-ended. See the second diagram in #17, the v- would have to be a common wire to other channel. One must be carefull not to take reference from the wrong context to avoid all the misunderstanding.[/COLOR]

[COLOR=000000]Also, no phase splitter is needed because the source is XLR (balanced). As for the RCA input, only ½ of the input is used and the efficiency is roughly dropped 50%. In other words, the RCA input will not take advantage of this design. You must use a balanced source to get the best out of the WA22.[/COLOR]

[COLOR=000000]Hope that clarifies.[/COLOR]

[COLOR=000000]-Jack[/COLOR]

 

[Solude]

No you aren't.  You are getting a balanced signal into the transformer BUT single ended out.  Or put another way on one side, +4V and -4V = 8V output.  But the connections are single ended.  The diagram shows that.  Look at where the misleading 3 pin goes... GROUND on the TRS.
 
All of this ignores that if you pop the top... its wired single ended on ALL jacks.  Case closed

 

[Solude]

I should add... its also THE RIGHT WAY TO DO IT  Balanced output with tubes and transformers is dangerous, read fire hazard, unless done right.  I believe Eddie Current builds their balanced transformers around a protection scheme that deals with winding failure.  I'm no transformer expert, Kevin or Craig can explain it better.

 

[grokit]

Since Woo Audio describes the WA22 on its web page as a

Fully Balanced Headphone Amplifier
Balanced design from input to output, Class-A, All Tube Drive, Output Transformer Coupled

Maybe you could prove your case to the FTC or whoever can enforce false advertising claims.

Otherwise I'll assume that you're "taking reference from the wrong context" :rolleyes:​

http://www.wooaudio.com/products/wa22.html

 

[Solude]

Sigh this comes up so often that I keep a photo in my gallery for times like this...
 

 
That's the TRS on the top.  Count the wires

 

[grokit]

Either Woo Audio is lying, or there is more than one interpretation of what exactly qualifies as a "fully balanced output". I have seen this debate devolve into a circular argument more than a couple of times over the years so I think the latter applies.

Again if you have a case, go on a crusade to stop this false advertising travesty. Why waste your time trolling on the Woo thread?

 

[Jhawkins]

Thanks for the photo.  Do you have any photos of a balanced output for example.  Thanks.