[atbglenn]

Quote:

Originally Posted by sclamb /img/forum/go_quote.gif LOL That would definitely ruin the sleek asthetics and fabulous build quality of my black beauty. I will try and find some very thin gasket type material and sit that between the casing and the top plate. The smallest gap should be enough to cut the amplification of the transformer sound.

I would try some Mortite caulking putty applied to the inside of the top plate and maybe a little on the internal sides, but not on the transformer. It should dampen the 50hz resonance. Since Mortite never hardens, it can be removed easily

 

[sclamb]

Quote:

Originally Posted by atbglenn /img/forum/go_quote.gif I would try some Mortite caulking putty applied to the inside of the top plate and maybe a little on the internal sides, but not on the transformer. It should dampen the 60hz resonance. Since Mortite never hardens, it can be removed easily

LOL!! I could fit some double glazing on the casing and have a picture window showing the transformer

Thanks for the tip - not sure what the UK equivalent would be though.

 

[atbglenn]

Believe it or not, in the old days some acoustic suspension speaker manufactures used Mortite to seal their drivers to the front baffle.

 

[jamato8]

Yep, it dampens. It doesn't have to cost an arm and leg to work. All you want is dampening properties.

 

[sclamb]

I asked Jack directly again today and Jack confirmed in an email to me that the WA6 SE amp design is compatible to a 274B rectifier.

However, he went on to say he tested multiple tubes on the same amp. It appeared that there was a strong flash in a few isolated cases. However, he said that a brief light white flash need not be worried about, which is at odds with what people here are saying in that such a flash is not good for the tube.

Given that there was only one other person that had seen this flash/sparking issue, perhaps there are some bad Princess 274B tubes out there and a replacement would be fine. If however a replacement has the same issue, and given that Jack sees the design as compatible with the 274B rectifier, then I don't know where to go from there.

 

[takezo]

hey sclamb,

i just realized you have the SE maxxed... the pics we've been looking at as a
reference is the stock SE... i'm piqued to know if there's any difference in the
circuitry layout... can you provide pics of the internals? if you don't have an
image hosting service you can sign up at photobucket, they're pretty reliable.

i've been playing both the princess and eml 274b the past week and neither
have had any spark or sound degradation issues with my heavily modified wa6...

 

[Gradofan2]

Quote:

Originally Posted by takezo /img/forum/go_quote.gif hey sclamb, i just realized you have the SE maxxed... the pics we've been looking at as a reference is the stock SE... i'm piqued to know if there's any difference in the circuitry layout... can you provide pics of the internals? if you don't have an image hosting service you can sign up at photobucket, they're pretty reliable. i've been playing both the princess and eml 274b the past week and neither have had any spark or sound degradation issues with my heavily modified wa6...

Do the mods include a reduction in the PS Filter cap value, or the addition of a resistor to control the current flow to the tube, or any other similar mods to reduce the current peaks on the rectifier tube?

If not, then can we conclude the "flash" issue with the SE is not an issue with the standard WA6 Maxed - and that it is safe to use the SP 274B MP with the standard WA6 Maxed???

Of course, the added power output of the SE may be a factor, that is not present in the standard WA6 Maxed, with lesser power.

 

[jamato8]

There isn't any added power in the SE, just a little different power supply. The amps put out the same amount of power, they use the same tubes.

 

[Gradofan2]

Quote:

Originally Posted by jamato8 /img/forum/go_quote.gif There isn't any added power in the SE, just a little different power supply. The amps put out the same amount of power, they use the same tubes.

I think Jack reported to me that the WA6 SE has greater power output than the WA6 - as I recall he indicated the SE has about 1 watt per channel.

Are you suggesting... he was wrong when he suggested to me the SE has greater power output than the WA6?

Though... in thinking about it... I may have read that elsewhere... Jack may have reported that the standard WA6 had about 400 mW per channel. But, I'm pretty sure he indicated the WA6 SE was more powerful.

 

[Ragonix]

Quote:

Originally Posted by sclamb /img/forum/go_quote.gif Given that there was only one other person that had seen this flash/sparking issue, perhaps there are some bad Princess 274B tubes out there and a replacement would be fine. If however a replacement has the same issue, and given that Jack sees the design as compatible with the 274B rectifier, then I don't know where to go from there.

There was at least 2 others that saw the white fash.

 

[jamato8]

If he is running it at a higher voltage and biasing more then maybe it does. That would also mean it draws more current from the rectifier tube. You can't get more by drawing the same amount of current and voltage.

 

[dan_can]

I noticed 274b flashes on start up on my max'ed out WA6 SE today.

 

[takezo]

has anyone done a test of the princess 274b with a simple tube
tester before using it for the first time in the wa6? if so, what kind
of reading did it give then and now, after the sparks?

mine hasn't sparked yet and emission test on a tv7du showed very
strong when i first received it... 65/64 with 40 being approx. 65%.

 

[Gradofan2]

Quote:

Originally Posted by dan_can /img/forum/go_quote.gif I noticed 274b flashes on start up on my max'ed out WA6 SE today.

So... is that 3 persons who have now noticed the tube flash with the SE... but... none with the standard WA6???

This seems to be occuring too frequently to be just a bad tube "here and there." It is appearing to be more likely a compatibility issue.

But... I still wonder why it seems to more commonly occur with the SE, than the standard WA6.

 

[sclamb]

Quote:

Originally Posted by takezo /img/forum/go_quote.gif hey sclamb, i just realized you have the SE maxxed... the pics we've been looking at as a reference is the stock SE... i'm piqued to know if there's any difference in the circuitry layout... can you provide pics of the internals? if you don't have an image hosting service you can sign up at photobucket, they're pretty reliable. i've been playing both the princess and eml 274b the past week and neither have had any spark or sound degradation issues with my heavily modified wa6...

I can try and do that. What precautions do I need to take when removing the bottom cover of the transformer unit as I understand from previous advice that there is a high voltage remaining within the capacitors?
Is there a way of draining the capacitors?

Happy to take some pics but don't want to die trying