Pass Labs 250.8

0 Members and 1 Guest are viewing this topic. Read 6321 times.

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #20 on: 11 Apr 2017, 03:25 pm »
The Pass Labs has 2 separate PSU units the one for standby just keeps the standby circuit powered
it keeps nothing warm

RDavidson

  • Full Member
  • Posts: 2202
Re: Pass Labs 250.8
« Reply #21 on: 12 Apr 2017, 04:04 am »
When I say "warm" I'm not meaning physically warm. Sorry for the confusion. What I mean is when the standby switch is in use, the unit is drawing a few watts of bias on the output stage. This keeps the output stage lightly idling (what I meant by "warm") and more ready to go when taken out of standby. So, going from standby to fully on should take less time for the amp to come up to optimal operating temp (and lowest distortion).

G Georgopoulos

  • Restricted
  • Posts: 1254
Re: Pass Labs 250.8
« Reply #22 on: 12 Apr 2017, 06:01 am »
R.D. is right regardless,i have designed class-a amps and i can say it takes roughly half an hour to stabilise thermally the amp (heatsink and power transistors junctions)

cheers

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #23 on: 12 Apr 2017, 12:39 pm »
I spoke to Pass Labs about this , in fact I was also told there is zero
difference from using the rear switch or standby. The standby is only
powered for convenience nothing more .

Big Red Machine

Re: Pass Labs 250.8
« Reply #24 on: 12 Apr 2017, 01:16 pm »
So how about the sound? I have considered Pass again after the .8 versions came out but did not go that route. I have owned a 350.5. There seems to be a preference for the .8 versions and I forgot why that is. I have also searched some Audiogon threads where occasionally a discussion comes up comparing Pass to Rowland and others. This 250.8 is certainly a beast and beautiful to look at.

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #25 on: 12 Apr 2017, 02:14 pm »
I have owned many amps but the last couple years I have used a pair of tube monoblocks , The pass labs is a bit more detailed/ forward  and faster than my current tube amps not by much . Also the 250.8 drives my Pearl 3's better . I have had very limited time to really sit down and listen but hope to later this week

Big Red Machine

Re: Pass Labs 250.8
« Reply #26 on: 12 Apr 2017, 03:58 pm »
Which tube amps?

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #27 on: 12 Apr 2017, 05:03 pm »
http://www.audiocircle.com/index.php?topic=149605.0

I have tried many amps and always kept these , they are that good

I.Greyhound Fan

Re: Pass Labs 250.8
« Reply #28 on: 12 Apr 2017, 06:19 pm »
So how about the sound? I have considered Pass again after the .8 versions came out but did not go that route. I have owned a 350.5. There seems to be a preference for the .8 versions and I forgot why that is. I have also searched some Audiogon threads where occasionally a discussion comes up comparing Pass to Rowland and others. This 250.8 is certainly a beast and beautiful to look at.

There are some people who prefer the 0.5 series over the 0.8 series.  I have read that they feel that the 0.5 has more weight or body to the music while the 0.8 has more air and transparency and a lighter feel.  I only have an original X250  to go by. It is a great amp but could use a bit more transparency.   I hope to upgrade to an X250.5 in the next year.

RDavidson

  • Full Member
  • Posts: 2202
Re: Pass Labs 250.8
« Reply #29 on: 13 Apr 2017, 01:02 am »
I spoke to Pass Labs about this , in fact I was also told there is zero
difference from using the rear switch or standby. The standby is only
powered for convenience nothing more .

Interesting. This must be a functional difference between the X and XA series (the latter I'm much more familiar with). I was making an assumption that they were the same. And again, I've assumed wrong. :oops: Probably because the XA series are biased more deeply into class A (and take more time/effort to thermally stabilize), they benefit more when starting-up from "idle" versus cold start.....so the standby function provides this benefit.

RDavidson

  • Full Member
  • Posts: 2202
Re: Pass Labs 250.8
« Reply #30 on: 13 Apr 2017, 01:16 am »
There are some people who prefer the 0.5 series over the 0.8 series.  I have read that they feel that the 0.5 has more weight or body to the music while the 0.8 has more air and transparency and a lighter feel.  I only have an original X250  to go by. It is a great amp but could use a bit more transparency.   I hope to upgrade to an X250.5 in the next year.

That was not my experience when comparing the XA30.5 to the XA30.8. The XA30.8 was not only more pure sounding, surely benefitting from Nelson's learnings from First Watt, it also had MUCH MUCH more weight, volume, and bass. When I got the XA30.8, this is the first thing that hit me as a major difference / upgrade. I didn't expect this at all. Something else that struck me (going back to my use of the word "pure") was that the amp sounded less like an amp, if that makes any sense. I can definitely understand people preferring one vs the other. They're both wonderful. But in MY experience, no question, the .8 series is the superior music communicator.

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #31 on: 13 Apr 2017, 01:57 am »
The X250.8 is my first Pass Lab amp , I'm second guessing
my decision if maybe a XA200.8 might of been better .
I want to stay with a stereo amp but wondering the difference

Big Red Machine

Re: Pass Labs 250.8
« Reply #32 on: 13 Apr 2017, 10:47 am »
I'm with you on that. I personally would lean toward the XA series to get Class A playback. I liked the 350.5 I had but it was a boat anchor and in the end did not impress me. Hence the .8 and XA series come along and now we're talking.

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #33 on: 13 Apr 2017, 11:58 am »
http://enjoythemusic.com/superioraudio/equipment/1015/Pass_Labs_X250_8_Stereo_Amplifier_Review.htm

Interesting read   


From the time I spent with my 250.8 it might just be a keeper

RDavidson

  • Full Member
  • Posts: 2202
Re: Pass Labs 250.8
« Reply #34 on: 14 Apr 2017, 04:37 am »
The 250 model in the Pass line sits in sort of a sweet spot. It has a pretty good amount of Class A power (though not as deeply biased as the XA series) and plenty of class AB power for most of today's speaker systems (which usually include multiple drivers and crossovers). The XA series is sort of more niche. One has to more carefully consider their speakers, room, and listening preferences as going up the line (for more class A watts) is exponentially more expensive. The X series takes more of a Swiss Army knife approach. Yes, you're giving up some of that Class A magic (compared to the XA line), but you're gaining versatility. It's horses for courses.....unless you can afford the top of the line XA series or even the XS. $$$$$$$$$$$

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #35 on: 14 Apr 2017, 12:30 pm »
I have been through allot of gear over the years and I think
I am pretty satisfied with the pieces I ended up keeping . Now
hopefully I can just fine tune things and sit back and enjoy . I was
thinking the same thing as you on the amps , plus I listened all day
yesterday and really couldn't hear anything neg with my system .

AR Ref 6
Pass Labs 250.8
TotalDac Twelve / Antipodes DX V2
Joseph Audio Pearl 3's

The only thing I might do is demo a Passlabs 30 Preamp but from what I read
my Ref 6 is probably a better pre .

Big Red Machine

Re: Pass Labs 250.8
« Reply #36 on: 14 Apr 2017, 12:45 pm »
I'd keep the AR unit.

RDavidson

  • Full Member
  • Posts: 2202
Re: Pass Labs 250.8
« Reply #37 on: 14 Apr 2017, 12:55 pm »
Yeah. Keep your AR. I doubt the Pass preamp is "better," just different. You have a VERY nice setup. Fine tune it with some Herbie's stuff. Enjoy! :thumb:

OzarkTom

Re: Pass Labs 250.8
« Reply #38 on: 14 Apr 2017, 05:15 pm »
AR :thumb:

ddark65

  • Full Member
  • Posts: 483
Re: Pass Labs 250.8
« Reply #39 on: 14 Apr 2017, 07:34 pm »
Anyone ever had the chance to compare amps  Pass to AR