Pass Labs XA-30.5 AND why would this not be a good match for my Valencias?

I'm always wanting to try more power with my speakers so I picked up this Pass amp locally. I've had one in the past, a few First Watts , and always liked them. First thing is the XA30 didn't play well with my 10y pre amp. When I adjusted the volume it would make make a loud clicks with each notch up or down. So I used an autoformer passive volume control. This combo sounded nice with my book shelf speakers but with my Altec Valencia something didn't seem right. Could it be because they are 16ohm ? Could it be that after years with set tubes I just can't listen to solid state any more?

any thoughts or suggestions?
 

240sx4u

Technically It's LexusGuy
I'm always wanting to try more power with my speakers so I picked up this Pass amp locally. I've had one in the past, a few First Watts , and always liked them. First thing is the XA30 didn't play well with my 10y pre amp. When I adjusted the volume it would make make a loud clicks with each notch up or down. So I used an autoformer passive volume control. This combo sounded nice with my book shelf speakers but with my Altec Valencia something didn't seem right. Could it be because they are 16ohm ? Could it be that after years with set tubes I just can't listen to solid state any more?

any thoughts or suggestions?

Kinda hard to ascertain what the issue would be since you swapped two piece of gear at once. My guess is your preamp is putting out DC when adjusting the volume and the Pass amp doesn't like it. FYI. I had a Classe' amp that was also very sensitive to any DC and would go into protection.

Anyway, maybe it's just not a good match. Stranger things have happened!
 
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I like the Pass preamps, but their amps aren't my cup of tea. Keep in mind where a tube can 'overpower' some deficiencies in a system, a high quality solid state component will not. I'm not saying this is the issue, but it is a possibility.
 

Audionut

Next Round Is On Me
I have zero experience with the pass lab amps, but plenty with Altec speakers. I’ve found that because they are so efficient, more power isn’t necessarily better. Case in point is hooking up my solid-state Mcintosh integrated amp to the 604s, I sold the amp shortly there after.
As @AudioThesis noted; Altecs and tube amps just go well together and/or have good synergy. I have not tried EL34 but can highly recommend EL84, 6v6 300B and 2a3 amps. (2a3 are my daily drivers).
 
yeah I wanted to start a new thread about my recent 2a3 experience. My amp dose 2a3 /45 /46. I'd say I'm a 45 guy.... no reason except its just what I use. Never use a 2a3 I'm not sure why I have some, maybe because I'm stubborn I thought I was too good for a 2a3? IDK? Like it was too much power? So using the above Altecs, my least efficient speakers, I figured I'd try them because I had them laying out. I had before but I was never drawn into them. What I did different this time is I used them with the 16 ohm tap on my amps. I was doing some casual listening and put on Deja Vu. I'm not that familiar with it but I was listening and on the my computer at the same time... all of a sudden it grabbed me. I was like holy crap it sounds amazing. I ended up flipping record after record.. then some digital. Maybe the best I have heard my Valencia's sound. I have been going strong no desire to change speakers or tubes. I did for a minute throw in the 46, because a couple months ago I really enjoyed it. I guess the extra couple watts I'm getting really helps.
 
I think the gain structure between the source, a pre-amp, amp and speaker is one of the least talked about but most important aspects of system matching. I have been struggling as of lately to get this right and wish I could expound something knowledgeable and interesting to help shine some light on this but I'm kind of clueless trying to figure this out. I will say that, in my experience, specs don't tell the whole story.

I have a cheapo Chinese pre amp (I'm reluctant to call it a pre amp, more like an Iphone booster). When in my big rig the music just jumps out of the speakers. My "audiophile" preamp sounds so boring in comparison but has extension and detail galore. My point is, it's not just the amp driving the speakers (although that has to be right) it's the entire system gain structure. There is something to be said for a whole systems from Audio Note and especially Shindo that gets the gain right from needle to cone.
 
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Tillerman

Junior Member
My point is, it's not just the amp driving the speakers (although that has to be right) it's the entire system gain structure. There is something to be said for a whole systems from Audio Note and especially Shindo that gets the gain right from needle to cone.
Totally agree. I have been on a similar quest to get the right synergy with components and gain.
 
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So I accidentally ended up with a full ( almost full) Thomas Mayer set up, Amp, Pre and Phono. I have yet to deal with any hum, gain, weirdness... So when experimenting with more power i'm kind of narrow path. Whole systems can be limiting for us that like to tinker. I'm left with only speakers to match with my very low power.
 

JohnVF

Administrator
Staff member
I think the XA-30.5 is a descendent of the Pass Aleph 30 I have. If it does have a lot in common with the Aleph series of Class-A amps, its sensitive to both input and output loads. It's also a very neutral amp that won't inform the sound or cover up much of anything. The sound of the amp itself, as much as there is a sound to it, is very neutral but with that class-a sweetness. It's an excellent amp for, say, Quad 63s. Not sure about Altec Valencias (they're not my personal cup of tea, just like this amp might not be somebody's cup of tea).
 

Audionut

Next Round Is On Me
So I accidentally ended up with a full ( almost full) Thomas Mayer set up, Amp, Pre and Phono. I have yet to deal with any hum, gain, weirdness... So when experimenting with more power i'm kind of narrow path. Whole systems can be limiting for us that like to tinker. I'm left with only speakers to match with my very low power.
Well that’s a thread in itself.
 
I think the XA-30.5 is a descendent of the Pass Aleph 30 I have. If it does have a lot in common with the Aleph series of Class-A amps, its sensitive to both input and output loads. It's also a very neutral amp that won't inform the sound or cover up much of anything. The sound of the amp itself, as much as there is a sound to it, is very neutral but with that class-a sweetness. It's an excellent amp for, say, Quad 63s. Not sure about Altec Valencias (they're not my personal cup of tea, just like this amp might not be somebody's cup of tea).

The 30.5 is not neutral - it falls on the warm side.

One other consideration (besides mismatch between preamp/amp) is that the 30.5 might need juice to 'wake up'. I can't remember if that was the case when I had one or not its been so long.
 

JohnVF

Administrator
Staff member
The 30.5 is not neutral - it falls on the warm side.

One other consideration (besides mismatch between preamp/amp) is that the 30.5 might need juice to 'wake up'. I can't remember if that was the case when I had one or not its been so long.
I'm also kind of looking at it in respect to SET world, as far as neutrality.

The Aleph 30 was very preamp specific and I recall it wanting a bit to wake up. If running it with super efficient speakers...yeah, it might not be waking up. I was running it with 87-ish db speakers so it was pushing something.
 
So I accidentally ended up with a full ( almost full) Thomas Mayer set up, Amp, Pre and Phono. I have yet to deal with any hum, gain, weirdness... So when experimenting with more power i'm kind of narrow path. Whole systems can be limiting for us that like to tinker. I'm left with only speakers to match with my very low power.
There is something to be said about a system designed to work in concert. The AN stuff seems to have this down, and my own Dennis Had amp and preamp function as a single component. That being said, you’re stuck with 1.5wpc, which is pretty limiting even with speakers of 100dB efficiency. If you think you might like the Pass sound, think about trying a Firstwatt F4 (or DIYAudio version) run off the outputs of the 46 SET amp. This should give you nearly all the character of your 46 amp with enough power to run a variety of speakers.
 
"There is something to be said for a whole systems from Audio Note and especially Shindo that gets the gain right from needle to cone."

👍👍👍👍👍👍👍
 
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