Pass amp confusion!!!

[lacey007]

Hello all, I am new to this site and understand it is mainly for DIY but perhaps a few of you can help. I currently have a pair of Pass XA160 Mono's....not the .5 series, that were purchased in 2004. My confusion is going to a new X350.5 or staying where I am. Running a Pass X-1 pre and JM Lab Diva Utopia Beryllium speakers and a pair of Alto Utopia Berullium speakers(HT sooner or later.) The masses, including Kent at Pass Labs says it is a move in the right direction. Better detail on top, better space and dynamics with the 350.5. I have had all the original X series amps as well as a 250.5 before getting the XA160's. Can't afford to move to XA100.5 or the XA160.5's right now. Any opinions or members that have had both at some point? Thanks for the help all.

[Melon Head]

Most of the people here including myself are deperados so it is unlikely you will find someone who has owned both, except for Nelson that is.

I just checked the specs of those speakers.
Nominal impedance: 8Ohms - Good
Sensitivity: 90dB/2.83V - OK
Minimum impedance: 3 Ohms - Not so good

The .5 amps are better at driving difficult loads compared to the original XA amp. I would put your speakers in the difficult load category (not extemely difficult though)

The X350.5 is biased significantly higher (Almost double) than the X250.5. So just from a technical point of view and without actually hearing them the X350.5 does seem like a good match with your speakers.

I am sure Nelson will probably have something to say about it though.

Is there any chance you can demo the X350.5?

[lacey007]

Thank you for the input and you are right. These speakers do have a big dip. I think I am going to pull the trigger in the 350.5. I wish I could audition it but can't. I love the looks of my XA160's but hate the heat. Love the smooth sound but miss the dynamics of more pore power. Thanks for the help, Pass says the 350.5 is a better match in terms of overall transparency, dynamics and space while maintaining a smooth sound. Thanks again for the informative response, I do appreciate it.

[jacco vermeulen]

Sensitivity of the Diva Utopia Be is more like 87dB/W.m
Other option would be to upgrade to the later Utopia model, like the Scala, just a couple of inches higher and easier to drive.

Current model types are starting to come out secondhand for decent price levels, i'm in the market for buying the larger Maestro, provided i don't run into a fool who wants to part from a set of Stellas (plenty of fools out there).

[lacey007]

You know, I have listened to the newer models but I prefer the sound of the older line for some reason which is why I am keeping the Alto Utopias as well. I did think about moving up though. I just sold the XA160's so I do hope the 350.5 works better for me. I love the mono's but I also like the simplicity of a single amp as well. The XA160's into a lower load will actually cut it's power in half so I don't know if they ever actually performed to spec in my system with the 3ohm dip. That was one reason they changed the XA160.5 because customers were complaining about that. If I wanted to go to a Sonus Faber Guenari or Amati, I would run into issues or the Dynaudio C2 was also a consideration. All 4ohm speakers! Besides the XA160's were bought in 2003 so they are aging but I got 6700.00 for them. Might as well sell them while I can get the good price and in a year or two, the X350.5 should still pull 6k or so and the one I am picking up is only 7 months old and the design.

[jacco vermeulen]

The difference of locations on either side of a pond.
Overhere, an XA160 set did close to $30K, the write-off would balance a change of loudspeaker.

(Similar story with loudspeakers, on a different level, i gather. I built a number of Focal DIY loudspeakers since the '80s. For me, the Utopia 3 series is the first to really ring my bell)

[lacey007]

WOW!!!! Do yo know anyone interested? lol.. 15k?? I did like the Diablo Utopia. Maybe it was because of the room.

[Nelson Pass]

This is mostly a matter of whether you feel you need the
additional power offered by the 350.5. If the XA160's
play the speakers loud enough for you, probably you could
sit tight with them for a while.

[Melon Head]

Originally Posted by Nelson Pass

sit tight with them for a while.

Yes. There are also a few new products coming out of Pass Labs. It seems like they are single ended designs like the XA160 you already have.
However I would not be surprised if Nelson went the circlotron route capable of class B into low impedance loads.

Whatever is coming out it might be worth waiting for.
No need to rush this decision.

[lacey007]

Mr. Pass, it is great to hear from you! I agree with you. I was going to keep them but there are two other factors that play into this and you covered one of them. There is a chance I may move to the Dynaudio C-2's for a journey with them. The other is the heat these beautiful mono's throw into my small 13x12 dedicated room. Am I correct in my assumption that there may be minimal sacrafice across the board by getting the 350.5? Are there any modifications available to the XA160? I assume not but it is worth a shot. Thank you for your input, it is greatly appreciated. Also, to melon head: I will look into this and thanks for the reply as well. I have been a dedicated Pass Labs used since 1998 going through the entire X series line-up through the X600's and some Aleph amps as well. Love it all! This my 14th Pass amp! I guess you can say I am a fan!