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Pass Labs XA30.8

Hi all,

I had the opportunity to audition the Pass Labs XA30.8 at a dealer was really like the whole presentation - huge,deep soundstage with great depth.

My preamp is Simaudio Moon 390. I am wondering if anyone here is running this combo - Moon 390 with Pass Labs XA30.8s.

My speakers are fairly efficient (92.5dB).

While my current combo (Moon 390 preamp and Moon 330A power amp) is great, the presentation is a little in your face. It feels like I am sitting in the front row with the band right in front. I want a more laid back presentation and hence the mind flirtation with the XA30.8s :)

Appreciate any input if anyone is running this exact combo. Please note I am only looking at XA30.8s and not the X series or any of their Class A mono blocks.

Thanks!
sim_audio_nerd
mikem
260 posts
 
I think the 30.8 would fit nicely in your system.. It’s a beast! Yet very detailed And delicate when it needs to be..  
georgehifi's avatar
georgehifi
10,312 posts
 


sim_audio_nerd OP the presentation is a little in your face. It feels like I am sitting in the front row with the band right in front

Your problem is too much gain with very efficient speakers.
The Pass 30.8 only needs 0.7v input for it to give full output. Any source is 2v or more even.
Can you see that you definitely don't need any more gain from an active preamp.
If your source has volume control use it direct into your 30.8
If you don't have volume control in your source, then try the next best, a 10kohm passive preamp as Nelson below will tell you..

Nelson Pass,

“We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.

Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.

Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.

What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp.”



 Cheers George
aberyclark
1,355 posts
 
Low gain is ket with high efficient speakers. More so with Tubes in the system (tube hiss can get super loud). I have the FW J2 and BHK Pre Combo...very quiet. The FW is super low gain.
georgehifi's avatar
georgehifi
10,312 posts
 
sim_audio_nerd

Just noticed you also are now using a ModWright PH 9.0 phono which has up to 66dB!!! of gain also, you have so much gain, do what I suggested in my first post, two posts back. 
You’ll not only have a a more palatable presentation instead of what you said "presentation is a little in your face", but also the background should be much quieter, as your then using all of what the cartridge is giving instead of shoving half of it down to ground and wasting it.

Cheers George
alfau7's avatar
alfau7
72 posts
 

Sim audio nerd

Iy would be interesting to know if you finally got the car 30.8 and which are your impressions compared with the moon 330? Thanks

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