Hey guys.
Just to let you know, I bought a Pass Labs X150.5 the other day. It's been 'burning in' for a couple of days. I had a Mark Levinson 432 before that which I had some issues with. I won't go into that here, but after returning the amplifier I reverted to my old Proceed BPA2 while I was looking for a new amplifier.
Here are some brief thoughts on the sound quality of these three ampliifiers as used with the Summits.
Proceed BPA2: 125 Watts per channel into 8 Ohms with a power increase into 4 ohms and some ability to drive 2 Ohms for brief periods. A very well built and slightly 'dark' sounding amplifier. A little muddy in the bass in absolute terms with good dynamics. Wide soundstage but imaging a little blurred. Power wise, the Proceed had no problems driving the Summits to loud levels. This is a good budget choice for those wanting to move to a low cost pre-power option with either Summits or Vantages.
Mark Levinson N0. 432: Whew! What can I say? This monster is built like a tank with power to burn. 400 watts per channel into 8 Ohms, 800 into 4 Ohms and very good ability to drive into 2 Ohms if required - but it can get hot doing this. This amplifier is NOT neutral sounding. It has a slightly dark quality (a little like the Proceed) with very substantial bass punch. HUGE dynamics. A wide soundstage with pinpoint imaging. Voices sound a little recessed but everything is there, if a little restrained. The Mark Levinson has no problems driving anything. I reckon you could hook a small town up to it and it would supply all electricity needs without raising a sweat. One thing I should say; I am now thinking the Mark Levinson is not a good match with Summits. It only comes into it's own when driven hard with say... Revels or something like that. The magic first watt is not Mark Levinson's forte.
Pass Labs X150.5: This amplifier is not a monster like the Mark Levinson. Still, it does okay with 150 watts into 8 Ohms and increasing to 300 watts into 4 Ohms. I have no specifications or measurements of it's ability to drive 2 Ohms. The amplifier is pretty much of Mark Levinson build standards but this is where similarities end. The Pass does not have the Mark Levinson's persistent bass punch. This was evident on first listening. Don't get me wrong, the bass is there but it's more like Chuck Norris rather than Mike Tyson. Chuck will only hit when he needs to and you won't get up after being hit. Mike just keeps punching - and it hurts but it's not going to kill you (not straight away anyhow). I think maybe the Mark Levinson tends to deviate from the strictly neutral - this is not entirely what I desire and is not the reason I bought Summits in the first place. The imaging and the soundstaging of the Pass amplifier is of Mark Levinson standards but there is no 'hash' or 'haze' to interfere with the music. It's like the music is coming from deep space. There is much more 'air' to the music and little details seem to be more easily heard than through my other two amplifiers. I am wondering if this particular Pass amplifier (the lowest power in the range) is more suitable for more sensitive speakers like the Summits. I know the Pass runs in pure Class A for 50 or 60 watts - the side heat sinks run VERY hot even at idle. So perhaps the Pass is more capable of delivering the magic 'first watt' than my other amplifiers - this is not to say the Pass X150.5 won't boogie. It can go VERY loud driving insensitive speakers, but we're talking about Summits here. Speaking of which, the Summits seem to soak up what the Pass provides and initial indications are that this amplifer and speaker make a very nice combination.
Just some thoughts... here's a pic:
Just to let you know, I bought a Pass Labs X150.5 the other day. It's been 'burning in' for a couple of days. I had a Mark Levinson 432 before that which I had some issues with. I won't go into that here, but after returning the amplifier I reverted to my old Proceed BPA2 while I was looking for a new amplifier.
Here are some brief thoughts on the sound quality of these three ampliifiers as used with the Summits.
Proceed BPA2: 125 Watts per channel into 8 Ohms with a power increase into 4 ohms and some ability to drive 2 Ohms for brief periods. A very well built and slightly 'dark' sounding amplifier. A little muddy in the bass in absolute terms with good dynamics. Wide soundstage but imaging a little blurred. Power wise, the Proceed had no problems driving the Summits to loud levels. This is a good budget choice for those wanting to move to a low cost pre-power option with either Summits or Vantages.
Mark Levinson N0. 432: Whew! What can I say? This monster is built like a tank with power to burn. 400 watts per channel into 8 Ohms, 800 into 4 Ohms and very good ability to drive into 2 Ohms if required - but it can get hot doing this. This amplifier is NOT neutral sounding. It has a slightly dark quality (a little like the Proceed) with very substantial bass punch. HUGE dynamics. A wide soundstage with pinpoint imaging. Voices sound a little recessed but everything is there, if a little restrained. The Mark Levinson has no problems driving anything. I reckon you could hook a small town up to it and it would supply all electricity needs without raising a sweat. One thing I should say; I am now thinking the Mark Levinson is not a good match with Summits. It only comes into it's own when driven hard with say... Revels or something like that. The magic first watt is not Mark Levinson's forte.
Pass Labs X150.5: This amplifier is not a monster like the Mark Levinson. Still, it does okay with 150 watts into 8 Ohms and increasing to 300 watts into 4 Ohms. I have no specifications or measurements of it's ability to drive 2 Ohms. The amplifier is pretty much of Mark Levinson build standards but this is where similarities end. The Pass does not have the Mark Levinson's persistent bass punch. This was evident on first listening. Don't get me wrong, the bass is there but it's more like Chuck Norris rather than Mike Tyson. Chuck will only hit when he needs to and you won't get up after being hit. Mike just keeps punching - and it hurts but it's not going to kill you (not straight away anyhow). I think maybe the Mark Levinson tends to deviate from the strictly neutral - this is not entirely what I desire and is not the reason I bought Summits in the first place. The imaging and the soundstaging of the Pass amplifier is of Mark Levinson standards but there is no 'hash' or 'haze' to interfere with the music. It's like the music is coming from deep space. There is much more 'air' to the music and little details seem to be more easily heard than through my other two amplifiers. I am wondering if this particular Pass amplifier (the lowest power in the range) is more suitable for more sensitive speakers like the Summits. I know the Pass runs in pure Class A for 50 or 60 watts - the side heat sinks run VERY hot even at idle. So perhaps the Pass is more capable of delivering the magic 'first watt' than my other amplifiers - this is not to say the Pass X150.5 won't boogie. It can go VERY loud driving insensitive speakers, but we're talking about Summits here. Speaking of which, the Summits seem to soak up what the Pass provides and initial indications are that this amplifer and speaker make a very nice combination.
Just some thoughts... here's a pic:
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