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Old 6th February 2014, 08:45 AM   #1
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Default pass x250.5 - x250.8

dear nelson
are the owner of a wonderful amp x250.5
I would like to know the most important differences between my model and the new x250.8

regards Caesar
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Old 6th February 2014, 03:42 PM   #2
fpitas is offline fpitas  United States
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Some reading from the Pass Labs site:

https://passlabs.com/products/amplifiers/point-8

The 2014 Brochure at the bottom of the page has more information.
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Old 6th February 2014, 05:37 PM   #3
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Fundamentally, the .8 series sounds better than the .5

Of course, this is something you would want to determine for yourself.

Technically, the 250.8 has a slightly larger power supply (more capacitance),
more output stage (56 output devices vs 40), larger heat sinks, and more bias
on the front end and the output stage. There is also a larger percentage of
the output stage single-ended bias. The Class A output figure is larger.

The amplifier has a higher input impedance and lower noise. It has no
compensation capacitors in the circuitry and operates with lower feedback.
When it is turned off, the power consumption goes to less than a watt.

There are other technical innovations which we are not choosing to disclose.

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Old 6th February 2014, 06:03 PM   #4
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i dont quite understand what you mean.
i bet if i read the serv manual it would all come together. if you email it to me ill send it right back!!

:-) :-D
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Old 6th February 2014, 06:11 PM   #5
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What parts of larger and more and better are not clear?

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Old 6th February 2014, 07:01 PM   #6
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Quote:
Originally Posted by Nelson Pass View Post
Fundamentally, the .8 series sounds better than the .5

Of course, this is something you would want to determine for yourself.

Technically, the 250.8 has a slightly larger power supply (more capacitance),
more output stage (56 output devices vs 40), larger heat sinks, and more bias
on the front end and the output stage. There is also a larger percentage of
the output stage single-ended bias. The Class A output figure is larger.

The amplifier has a higher input impedance and lower noise. It has no
compensation capacitors in the circuitry and operates with lower feedback.
When it is turned off, the power consumption goes to less than a watt.

There are other technical innovations which we are not choosing to disclose.

are this custom made sinks? or is it something one can get of the shelf?
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Old 6th February 2014, 09:17 PM   #7
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They're probably custom, I've never seen any exactly alike only similar.
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Old 7th February 2014, 06:44 AM   #8
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Location: sondrio
Thank you very much nelson for having responded to my question.
is an honor to be able to speak directly with the designer of the best amplifiers in the world.
I know many audiophiles who own amplifications pass and I'm excited.
I hope to listen to a short new series devices .8

and ... also soon be able to get hold of a pre-amp to match my x250.5 xp.20 moment

regards Caesar
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Old 7th February 2014, 01:19 PM   #9
CeeVee is offline CeeVee  Portugal
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Quote:
Originally Posted by AudioSan View Post
are this custom made sinks? or is it something one can get of the shelf?
..yes custom Pass heatsinks from way back...very nice design as usual.
You can see the similarity with firstwatt heatsinks....same designer ? don't know but i will bet it is. :-)

C

Last edited by CeeVee; 7th February 2014 at 01:22 PM.
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Old 7th February 2014, 01:51 PM   #10
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oh yeah
heat sinks are arranged vertically rather than horizontally as in the previous 250.5 and then, in theory, the heat dissipation is more effective
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