Pass XA60.5

[Bruce B]

Looks like JA reviews this amp in the new Stereophile, Jan '14.
His conclusion was "It is the best sounding amplifier I have ever used "

Can't get any better than that. Pair them with the Alexia's he reviewed last month (associated equipment) and you'll have a system for your lifetime.

Measurements had these amps putting out over 130w at 8 ohms and 210w at 4 ohms! Damn!

 

[rbbert]

Will there be a XA60.8 next month (like the upcoming XA100.8)?

 

[Bruce B]

Will there be a XA60.8 next month (like the upcoming XA100.8)?

I'm pretty sure there will.

 

[JackD201]

Gotta love companies that conservatively rate their gear

 

[rbbert]

Gotta love companies that conservatively rate their gear

Like all the XA.5 series, the spec rating is only for Class A operation, but it is true that AFAIK every Pass amplifier independently tested has easily exceeded its spec'ed power output.

 

[MadFloyd]

Looks like JA reviews this amp in the new Stereophile, Jan '14.
His conclusion was "It is the best sounding amplifier I have ever used "

Can't get any better than that. Pair them with the Alexia's he reviewed last month (associated equipment) and you'll have a system for your lifetime.

Measurements had these amps putting out over 130w at 8 ohms and 210w at 4 ohms! Damn!

I have my doubts that the 60.5 could drive the Alexias; I wonder if he used the amp with them...

I also read that the various models in the XA.5 series sound different with some saying that the 100.5 is the most tube like.

 

[rbbert]

I have my doubts that the 60.5 could drive the Alexias; I wonder if he used the amp with them...

I also read that the various models in the XA.5 series sound different with some saying that the 100.5 is the most tube like.

I'm pretty sure Bruce has some experience in both those areas

 

[Bruce B]

I have my doubts that the 60.5 could drive the Alexias; I wonder if he used the amp with them...

I also read that the various models in the XA.5 series sound different with some saying that the 100.5 is the most tube like.

Yes, as I stated above, the Alexia as well as the Vivid were the speakers he used.

 

[microstrip]

I have my doubts that the 60.5 could drive the Alexias; I wonder if he used the amp with them...

I also read that the various models in the XA.5 series sound different with some saying that the 100.5 is the most tube like.

The Alexia's have a very good efficiency - I measured that they are almost 2.5 dB more efficient that the Aida's and 7 dB more efficient that the Sonus Faber A1 Px. This efficiency will surely be a little reduced when we use them with a tube amplifier having a low damping factor.

 

[edorr]

I am planning to rotate one or two poweramps through my system in 2014, to see what works best with my Evolution Acoustics MM3s. One of the contenders is Spectral. Sounds like I may need to give the Pass XA series a whirl. Do you think I need the 60.5 or the 100.5?

Do they run very hot? I have a poorly ventilated room - and can't have very hot amps in summer. I read the 60.5 draws only 200w in idle, so 400w spaceheating is not too bad.

 

[Bruce B]

I am planning to rotate one or two poweramps through my system in 2014, to see what works best with my Evolution Acoustics MM3s. One of the contenders is Spectral. Sounds like I may need to give the Pass XA series a whirl. Do you think I need the 60.5 or the 100.5?

Do they run very hot? I have a poorly ventilated room - and can't have very hot amps in summer. I read the 60.5 draws only 200w in idle, so 400w spaceheating is not too bad.

The 60.5 amps would be all you need. I used the 100.5 amps and they were more than enough.

 

[Audioseduction]

Bruce, what kind of power can I expect out of my xa160.5s?

 

[Bruce B]

Bruce, what kind of power can I expect out of my xa160.5s?

If JA's measurements are any indication, I would expect 320 - 500 w/c

 

[Audioseduction]

If JA's measurements are any indication, I would expect 320 - 500 w/c

That's a lot of class A power!

 

[rockitman]

That's a lot of class A power!

Class A operation is only for the rated power. It switches to class AB to reach the power Bruce mentions.

 

[Audioseduction]

I see. Will I had it so loud it would make your ears bleed in the needle did not move, meaning I was in class A during play back.

 

[microstrip]

Class A operation is only for the rated power. It switches to class AB to reach the power Bruce mentions.

Class A power is usually rated at a nominal load of 8 ohms. Using speakers such as the Alexia will reduce it by a typical factor of 4.

 

[Frank750]

Class A power is usually rated at a nominal load of 8 ohms. Using speakers such as the Alexia will reduce it by a typical factor of 4.

XA160.5 / Specifications
Gain (db)
26
Power Output /ch (8 ohm)
160
Power Output /ch (4 ohm)
320
Input Impedance,(Kohms)
30 / 20
Leaves Class A @ pk Watts
320
Power Consumption (W)
600
Dimensions (W x H x D)
19 x 11.2 x 22.5
Unit Weight (LBS)
131
Ship Weight (LBS)
131

 

[Bruce B]

XA160.5 / Specifications
Gain (db)
26
Power Output /ch (8 ohm)
160
Power Output /ch (4 ohm)
320
Input Impedance,(Kohms)
30 / 20
Leaves Class A @ pk Watts
320
Power Consumption (W)
600
Dimensions (W x H x D)
19 x 11.2 x 22.5
Unit Weight (LBS)
131
Ship Weight (LBS)
131

Yeah, those are the specified measurements given by the manufacturer. Certainly not real world measurements.

 

[microstrip]

XA160.5 / Specifications
Gain (db)
26
Power Output /ch (8 ohm)
160
Power Output /ch (4 ohm)
320
Input Impedance,(Kohms)
30 / 20
Leaves Class A @ pk Watts
320
Power Consumption (W)
600
Dimensions (W x H x D)
19 x 11.2 x 22.5
Unit Weight (LBS)
131
Ship Weight (LBS)
131

Frank,

This will not add nothing new to the class A debate - the peak power rating is just the class A power x 1.414 x 1.414.

Pure class A is mainly a function of the idle current of the output stage. Manufacturers could specify it, but it would be meaningless for 99% of people. A quick guess finds it will be around 4.5A - a noticeable value, many class AB amplifiers have idle currents around 100 mA. I would expect Class AB power to around 300W at 8 ohm