[StereoNut]

Before I buy any, I just want to make sure that 12AU7A's are OK to use as a replacement to 12AU7's. 

They'll be used as back-ups for my Primaluna Prologue Premium tube pre-amp. 
http://www.primaluna-usa.com/product-main/prologue-premium/pro-prem-pre

Please advise/confirm.

Thanks,
SN

[paul79]

Depends on the brand... A can mean a more rugged tube. May also mean a controlled heater, but they are electrically identical. Feel free to roll away mang!

[StereoNut]

Thanks, Paul!  I'm not looking to "roll" as much as just having a second set of tubes "in da house" as backups. - SN

[rpf]

Don't buy any Bill; give me a call, I have extras.

[StereoNut]

Don't buy any Bill; give me a call, I have extras.

Thanks, Rob!

[GT Audio Works]

Before I buy any, I just want to make sure that 12AU7A's are OK to use as a replacement to 12AU7's. 

They'll be used as back-ups for my Primaluna Prologue Premium tube pre-amp. 
http://www.primaluna-usa.com/product-main/prologue-premium/pro-prem-pre

Please advise/confirm.

Thanks,
SN

Hey Bill, I have been waiting for an owners manual for my Dialogue Premium since I purchased it over a year and a half ago.
I have checked the site many times to see if it was available online..to no avail...well I just checked thru your link and there it is, an owners manual...WOW !! 
But I still cant find the info I am looking for....does the units output invert phase ? I would guess it does since the bass sounds  tighter when I invert my speaker cables. Have you tried inverting your cables ?  Assuming nothing else in your system inverts phase back again it should make a difference.   Greg

[StereoNut]

Hey Bill, I have been waiting for an owners manual for my Dialogue Premium since I purchased it over a year and a half ago.
I have checked the site many times to see if it was available online..to no avail...well I just checked thru your link and there it is, an owners manual...WOW !! 
But I still cant find the info I am looking for....does the units output invert phase ? I would guess it does since the bass sounds  tighter when I invert my speaker cables. Have you tried inverting your cables ?  Assuming nothing else in your system inverts phase back again it should make a difference.   Greg

I'm glad that my post helped you out Greg!  As far as phase goes, I've never given it a thought, so I haven't tried it!  I don't have anything in my system that allows me to invert phase to try it that way.

 Bill
(SN)

[paul79]

You got speaker cables Invert all you like.

[StereoNut]

You got speaker cables Invert all you like.