X350.5 vs. X350.8

[Dave_72]

Has anyone here made the comparison? If you did, was there a clear winner? What are the strengths and weaknesses of both? Also, which one runs hotter?

Thanks for your time in advance. Take care.

-Dave

[Cyclotronguy]

The one that idles at the highest wattage puts out the most heat. The one with the lower heat-sink efficiency is hotter to the touch.

At 120 Vac
350.5 typically 4.6A
350.8 typically 4.8A

Sinks on an X350.8 seem to run about 5 degrees C cooler to the touch than the X350.5's

Cyclotronguy

[Dave_72]

Originally Posted by Cyclotronguy

The one that idles at the highest wattage puts out the most heat. The one with the lower heat-sink efficiency is hotter to the touch.

At 120 Vac
350.5 typically 4.6A
350.8 typically 4.8A

Sinks on an X350.8 seem to run about 5 degrees C cooler to the touch than the X350.5's

Cyclotronguy

Thanks for the info. Does that translate to anything soundwise?

[cma29]

Originally Posted by Dave_72

Thanks for the info. Does that translate to anything soundwise?

Deeper Class-A bias so theoretically better sound. I have not heard either amp.

[Dave_72]

Originally Posted by cma29

Deeper Class-A bias so theoretically better sound. I have not heard either amp.

No problem. Thanks.

[zettelsm]

I didn't compare my X350.5 to the newer X350.8, but I did do a side by side (well really, top to bottom) comparison of my X350.5 to the X250.8

The short version -- the X350.5 got traded in for the X250.8

With my efficient speakers the X250.8 has plenty of power to reach crazy stupid loud levels and at saner levels brings more finesse, nuance, depth and texture to my music. Absolutely no fall-off in bass power. If anything, the .8 sounds as if it has another half-octave deeper articulate bass than its bigger brother.

I lived with the X350.5 for three years before making the change, and was really surprised how non-subtle the improvement was, even with the X250.8 new out of the box.

The .8 models all run higher bias current than their .5 counterparts, but as was pointed out their heatsinks must be more efficient since they seem to run cooler to touch. I don't notice much difference in how much the X250.8 heats the room, but the heatsinks are cooler to the touch than the X350.5 ever were.

[zettelsm]

I neglected the OPs request for strengths and weaknesses --

The overall impression of the X350.5 was, "Wow! Now that's impressive!"

The on-going impression I have of the X250.8 is, "Aaah, that's music!"

To my ears, the X250.8 has more nuance, low-level detail, is more liquid and relaxed and has a very 3D, very deep spatial presentation. Listening to good vinyl I've had those single-ended triode holographic moments I haven't had since, well, the last time I had a 300B amplifier in my system.

Steve

[Masterlu]

Steve... Welcome to AA!