VAC 30/70...pick your pre?

Charles, 

I think I am going to try NYC as it's only a couple hours from Philly; I don't know if they currently carry either of them though.  Texas is a bit far, although I do have plenty of airline miles, but they currently only have the 508, as the guy that originally bought the 508 traded it out for the 219.  
I will only have about 5 inches of breathing room up with the 219. 

I will only have about 5 inches of breathing room up with the 219.

Hmm. Both amps are specified as consuming 400 watts of power. (Although I’m a bit surprised that the 219ia isn’t closer to something like 300 watts, or even a bit less). Nearly all of that power will be converted into heat, and radiated directly upward. Hopefully that space is open at both the rear and the front, and hopefully the material that is above the amps is heat resistant (and won’t conduct the heat into a component that may be above that surface). Otherwise, and possibly even given those conditions, I would have significant concern even with the 10 inches of clearance you would have with the 508ia.

Best regards,
-- Al

Al, 

The space is open to the front, back, and sides (I use a Salamander triple 20); and although my current amp (though only 6L6 and not 845s) has 10 inches of clearance with about 350W consumption, I have added a small sheet of thermal radiant barrier with good results of keep heat down.    

Good!

As a point of information, though, your Melody SP3 is a class AB amp, and the power it draws will therefore fluctuate with the dynamics of the music, and will be much less than 350 watts most of the time. While the power consumption of the class A biased LM SET amps will be essentially constant at all times.

What will be converted into heat by the LM amps will be the power it draws from the wall outlet (nominally 400 watts) minus the power it delivers to the speakers (which is likely to be just a few watts most of the time, or even less). It’s a different story with class AB amps.

Best regards,
-- Al

Thanks Al! Wonderfully helpful