Pass labs XA60.5 anything wrong with them.


These amps, more often than other (pass lab amps) appear in the used market, from what I have observed.

I am considering getting one for my system (after listening of course). Moving up from an integrated, but as a noob, wondering why so many are in the used market.
essrand
Yup. TWO currently for sale. it is a conspiracy.
Do not let anyone tell you it is ony a coincidence.
She's right. I know 2 audiophiles that lost their lives with those damn XA60.5's. One minute its just sitting there floating calmly between your speakers, and without realizing it, the amp slips out of balance and starts spinning. It rips the speaker cables out of the binding posts and takes your head off just like a big weed whacker. I've seen pics of incidents involving double bi wiring and the images are horrific. Stay away from those amps. Its not worth the risk.
Wow!
The first two reponses are terrific!
Wish I could think of something that clever!

All I can think of to say is that they are only 60 wpc and probably the people
selling them need more power. Oh and being full Class "A" amps they are
going to run fairly hot, and it it summer so thenowners might want a cooler
running amp.
(Sorry I could not be as funny as the first two repondents.)
Yeah, that's possibly it, and imo, the bigger and more powerful Class A amps just sound better on the overall. Plus, you need pretty efficient speakers for the 60W amps to work, imo.
60 Watts is a lot of power even for speakers not so efficient. Lets say you have a speaker that outputs 89dB at 1Watt/1meter. That results in an SPL of 97dB at 3 meters with 64Watts. That is pretty loud unless your goal is permanent hearing loss. 100dB is standing next to a pneumatic jackhammer, for example. I guess the question is does a class A amp still sound as good at maximum output as it does at 1 Watt.
Nothing wrong with the 60.5's. For this line of amps, they are the cheapest mono blocks offered. If you are not set on monos, the XA30.5 is their stereo amp of the same design. I own it and the XA100.5's and they are much more alike than different. The 30.5 is about half the cost of the 60.5's.

All of their XA.5 amps put out much more power, maybe 3 to 4 times as much as their rating. Example: the 30.5 is rated at 30 wpc. That is the amount of pure class A. When Stereophile tested it, it put out around 130 wpc into 8 ohms and about 200 into 4 ohms. It just transitions to class AB after 30. I think you would be surprised at how loud even 10 watts can be but it is nice to have all that headroom.
I had some different model Pass amps and I thought the power rating was very conservative. I had the Aleph 0 rated at 40 watts/ch. It was a while ago, but it had no problem driving my B&W 802 s3's in a medium size room at fairly high volumes. At the time, I was interested in a Krell KAV 250 and had that in my system, as well. That was a nice amp too, but I ended up keeping the Pass. Power wasn't an issue.
I see, but imo, 89db sensitivity should be the cutoff point. Anything lower is taking a bit of a chance, imo. As for me, I'm looking at a pair of First Watts F4s in bridged balanced XLR mono operation. You have 100Wpc into 8 Ohms. However, you need a preamp with at least 14db of gain. And you need efficient speakers. My speakers are 94db sensitive, so no problem really. It's an interesting amp to say the least, and hand built by Nelson Pass!
07-11-13: Tonywinsc
60 Watts is a lot of power even for speakers not so efficient. Lets say you have a speaker that outputs 89dB at 1Watt/1meter. That results in an SPL of 97dB at 3 meters with 64Watts. That is pretty loud unless your goal is permanent hearing loss. 100dB is standing next to a pneumatic jackhammer, for example. I guess the question is does a class A amp still sound as good at maximum output as it does at 1 Watt.
This analysis does not take into account the dynamic range of the music, however, meaning the DIFFERENCE in volume between the loudest notes and the softest notes. Well engineered minimally compressed classical symphonic music, for example, can easily have a dynamic range of 30 db or more, and a few such recordings in my collection even exceed 50 db.

A dynamic range of 30 db means that 1000 times as much power will be required for the loudest notes as for the softest notes. 50 db means that 100000 times as much power will be required for the loudest notes as for the softest notes.

On many such recordings, I find that brief peaks reach 100 to 105 db at my listening position, although average levels may be in the 70's or even less. Due to their brevity, and the moderate average level, those peaks do not represent a threat to one's hearing.

On the other hand, many and probably most rock and popular recordings these days are compressed to a dynamic range that is in the single digits, meaning that less than 10 times as much power is required for the loudest notes as for the softest notes. Your conclusion would certainly be applicable in those cases, IMO.

One minor additional point: In your example, since two speakers are being driven the 97 db figure is likely to be around 100 db, and possibly as much as 103 db.

Regards,
-- Al
Thanks for that info. I agree 100 percent. :D
For sure, total dynamic range must be considered. If you have your stereo volume set for the quietest passages to be at 40dB or so, just above the average room background level, then you have 57dB of headroom (considering 97dB max). Of course, I typically have my volume set at a point where record background noise is just audible on my quietest records at the lead in groove. I think that gives me somewhere around 40-50dB of headroom which can get pretty loud, and then my wife makes me turn it down. In general, speakers have a linear output of SPL (in dB) vs. power up to around 100-105dB- some less, some more. That is a generalized statment- better to consult your owners manual for more accurate specs. What that means is you can pump more power into the speakers but they will not get much louder. Some of that extra power will just turn into smoke:)
Thanks for your response.

I rarely see Pass Labs amps for sale, and I would so like to experience them, given all the raves.

But seeing 3-4 being offered for sale made me think that maybe these are underpowered (or too entry level at $11000!) and people move on to higher powered amps. Though I think for me 60W is more than plenty.

I am finally on the path of moving off from my Jolida 801A, if I pull the trigger this might be a super big jump.
I had them for some time. I also owned the XA-100.5 and 30.5. To be honnest for the money the 30.5 and 100.5 were better. These amps I used with the XP-20 Now I use the X250.5, overwhole sound I prefer a lot more over the XA60.5. The slamm and speed in the low freq are better. it is still a very warm and musical amp. It is a little bit more open than the XA60.5 The XA100.5 were a lot better than the XA60.5. The difference between the XA30.5 and XA60.5 is smaller.
Thanks for highlighting the differences. So do you prefer the Class AB amp to the Class A amps? I always feel that Class A sounds better, and even Pass Labs says as much.
I thought I prefered the XA over the X series. I am not sure anymore. It has to do that I use the Purist Audio LE 2013 powercable. This gives me a much higher level out of the X250.5. I think I will go for the X600.5 later this year. There is a big difference in speed and slamm. Maybe the XA series are more warm sounding. Purist Audio powercables open up the mid freq a lot. Maybe this is the reason why I do not want to sound it more warm. I love the speed in the low freq. With both you cannot go wrong. One thing I know 100% sure, The next amp will be a Pass.
"Now I use the X250.5, overwhole sound I prefer a lot more over the XA60.5."

This is a very system (and listening preferences) dependent statement. For example, I auditioned the XA30.5 vs. the X250.5 on Thiel 2.4s. The X250.5 had some midrange harshness that made it slightly grating on the Thiel's and made the vocals (even Kanye West's) less natural. The XA30.5 has much more natural sweetness and a better soundstage (with those great vocals), but is somewhat weak in the bass. I think this is an issue with the XA series in general, which makes people think they don't have enough power, and draws them up the line (hence the XA60.5s becoming available). I personally love the XA amp so much (even though it's underpowered for my speakers) that I just dealt with the bass issue by adding a Thiel sub. I also know someone else who was looking into speakers with powered bass units for the same reason. In any case, the Pass amps are awesome, and the impression I've formed is that if you want great bass, you should go with the X.5 series, but if you want great soundstaging and vocals, you should go with the XA series. Also, just fyi, both of these amps just killed a McIntosh MC-402 which another Thiel 2.4 owner had loved.
"Now I use the X250.5, overwhole sound I prefer a lot more over the XA60.5."

This is a very system (and listening preferences) dependent statement. For example, I auditioned the XA30.5 vs. the X250.5 on Thiel 2.4s. The X250.5 had some midrange harshness that made it slightly grating on the Thiel's and made the vocals (even Kanye West's) less natural. The XA30.5 has much more natural sweetness and a better soundstage (with those great vocals), but is somewhat weak in the bass. I think this is an issue with the XA series in general, which makes people think they don't have enough power, and draws them up the line (hence the XA60.5s becoming available). I personally love the XA amp so much (even though it's underpowered for my speakers) that I just dealt with the bass issue by adding a Thiel sub. I also know someone else who was looking into speakers with powered bass units for the same reason. In any case, the Pass amps are awesome, and the impression I've formed is that if you want great bass, you should go with the X.5 series, but if you want great soundstaging and vocals, you should go with the XA series. Also, just fyi, both of these amps just killed a McIntosh MC-402 which another Thiel 2.4 owner had loved.
The harshness is also a limitation of the Thiel speaker. What I said: I use the Purist Audio LE 2013 powercable. Purist opens the mid freq. Totally no harshness in the Pl-200 from Monitor Audio. I played with the 30.5, 60.5 and 100.5 with the Pl-300 from Monitor Audio. The low freq. are awesome with the Pl-200. The cross over filter from the Monitor Audio are superior to the crossover filter of the Thiel loudspeakers. How do I know this? Very simple; the stage of the Pl-200 is a lot wider en deeper. Separation of instruments and voices is a lot better.
Bo1972, I have my sights on Pass Labs too. Or First Watt as I have very high efficiency speakers. Thanks for highlighting the differences. It does go against the grain of conventional thought ie Class A sounds better. However, differing opinions such as yours are ok with me.
When my Pass dealer asked what my preferences were, I said fast, accurate and dynamic, he said I would probably prefer the X series to the XA
Bo1972, do you prefer the X250.5 over even the XA100.5´s?
No, In prefer 100.5 over X250.5. But in the setting I use now I prefer the 250.5 over the 60.5. That is why I will choose for the 600.5 later. XA has a more musical sound compared to X series. But the drive and speed do a lot with the Pl-200 speakers. Since I use the Audioquest Redwood 2013 version ( mid's/high's is full silver and low freq. is copper) the timing and speed advantage of the X250.5 have gone to another level. I understand that in other settings peolple need the overwhole warmer sound of the XA series. My tweeters go even above 100khz. There is no harshness in the high freq at all. Do not forget that even the XA100.5 has a lot of drive in the low freq. But it is the speed and more drive of the X series ( 0.5) what makes the sound more stunning in my setting.I also use the Acapella pure silver ballanced cables to my X250.5. These have also a very open mid freq. Like the Purist Audio 2013 LE powercable. In my settings the XA could become too much of it. These days I use the Onkyo PR-SC5509 with my own way of Audyssey Pro measurement. I did a lot of testing with Audyssey in the last 2,5 years. Now I have a wider and even deeper stage than with the XP-20 which I owned for 2 years. I have also more drive and a better separation of instruments and voices than what I had with the XP-20. Even wenn I play extreemly loud my needle is almost not moving. I can play till about 118 db with the Pl-200 with ease. I measure at totally different places and hights compared to they way Audyssey does. So I become a superior drive, speed, more resolution and a far better individual focus of instruments and voices. I have even more micro information. I can let people hear words endings of songs they thought they knew. Now they hear the word ending of these songs at a ss, ttt or th. You even hear people better breathing during singing. Because roomcorrection is only 1/3 of the whole Audyssey system how I use it. Now I can crush most pre-amp till 10.000 dollar with ease. I win in every part. More drive, wider and deeper stage, more resolution, better articulation, more natural sound and a much better individual focus of instruments and voices. I still play stereo the most these days. I never heard a touchable 3-dimensional image this convincing in my life before. I use it for stereo and multi channel clients. Many clients with expensive stereo pre-amps now play with the Onkyo PR-SC5509 with my Pro measurement. What I did was comparing it with there expensive pre-amps. It was that superior that they could not go back anymore. Audio is for me comparing and showing the best sound what is possible these days. I only can say: Mannnn I love it!!
Here is my 2 cents as a happy owner of a x250.5.

Why do you see relatively more xa60.5 on the used market? I think it may actually boil down to something as much to do with economics as anything. I believe the 60.5 becomes a "stepping stone" model more than others because it is the entry path into the highly desirable monoblock models. And, at its $11k price it begins to get into the rarefied air of the 1 percenters who can more freely afford to trade up to the more expensive models such as the xa100.5. Unfortunately I cannot spend that much on an amplifier so I will just have to be satisfied with my x250.5 (which is a wonderful product in its own right, btw).

As for the common question of the "XA.5" versus "X.5" you might check out an article that Pass Labs staff themselves once pointed me to. I know nothing about the journalistic integrity of the Positive Feedback publication, but I do believe it captures the essence of the biggest differences between the class A and AB models. The article actually reviews the integrated models INT-30A and INT-150, but Kent English himself from Pass once told me that with the exception of the volume controls they are identical to the xa30.5 and x150.5 Check it out here: http://www.positive-feedback.com/Issue58/pass_labs.htm
To Be honnest I found the INT models not the best what Pass Labs makes. Wenn instruments and voices become too big in proportion the distance between you and the music is getting bigger. Beause you will loose intimacy. Often at show's people use the wrong brand of cables for Pass Labs. A voice is sometimes even over 1.5 metre. Then I ask the persons who gives this demo ( in my world they are fools) how big is your head? MIT and Shunyata with Pass Labs makes voices and instruments too big in proportion. People first have to learn and understand how big voices and instruments are in proportion in real. I had these conversations a few times with the people from Pass Labs. Many are capable to f....up a show with ease. Sharp individual focus of instruments and voices are a key to the absolute sound. Because the level in invlovement and emotion is Always bigger than played too big in proportion. The same as the difference between 2-dimensional and 3-dimensional is a big difference!!
How would Neotech cables work with Pass Labs?
I don't know them. In the US there are many cables which are not even here in Europe.
I did test many brands which are not well known in the last 15 years. Most of the time they are not bad at all. But I never heard one what was exceptional good. The biggest difference between Audioquest and other brands are a few important parts. In the past I Always needed to use a few brands to get all the parts ( properties) in a set.

- deep stage
- wide stage
- sharp individual focus of instruments and voices ( many cables give an image with instruments and voices too big in proportion)
- open mid freq.
- controlled and deep low freq with all layers auditionable.
- good timing, low freq. need to be very short in attack.
- exceptional good blacks. Black is the space between the voices and instruments with there acoustic info of the room were they were recorded.
- lots of resolution and open high freq.
- no harsness in any freq.
- authorithy in the overwhole sound.

The DBS which many Audioquest cables use give a much better timing and more blacks. At this moment I did not audition any cable with this exceptional stunning blacks. Blacks give you a more 3-dimensional and tochable image. Audioquest give you all these parts what should be there in a well balanced system. Powercables of Audioquest are good but not exceptional. That is why I am not interested in them. Purist Audio makes superior powercables compared to Audioquest.
Bo, I hear all the properties on your list with my Transparent Audio Ref XL cables. Transparents are individually matched to components and I've found them to be an excellent match with Pass Labs electronics.
The difference between Audioquest and Transparent is that the speed and blacks are better compared to Transparent. I heard there new cables at a show this year. I did not hear the level in blacks what the Audioquest can do. My new Redwood 2013 is even superior in speed compared to my old Valhalla. Attack in the low freq. are extreemly short.
Bo1972: Thanks for the detailed reply to my post. Much appreciated, and I'll make a note of it. Neotechs have UP-OCC copper (very pure) and UP-OCC silver (also very pure.) They are very high quality, and they're the OEM for more than a few cable companies. They're not real cheap, but they are excellent, as far as I know. However, if they don't interface well with Pass Labs/First Watt, then there's no point in me buying them, you know?
I Always say to clients; take your time and compare. I do the same ( a lot) so they should do the same. You only can spent your money once.
Bo, Was the system at that show identical to your system? If not, how can you be sure that what you heard is attributable to the cables? Power quality, electronic circuits etc all contribute to noise floor and level of blacks.

I can't make such a definitive statement as I've never heard the Audioquests in my system. I have heard various models at shows in completely unfamiliar settings and would not venture to attribute sonic qualities to them.

I'm just saying that I think Transparent and Pass work well together and in my system, I hear what you are describing as the strengths of Audioquest cables.
I did not say Transpanrent would not work fine with Pass Labs. Transparent is also a brand what does not do anything wrong. Everything is there. I have enough clients with Transparant. Maybe you should try Audioquest once. In all the sets were I used a lot of Audioquest you hear the high level in 3-dimensional and touchable image. For me it is now easy to hear what it does and wenn it is being used. The level in touchable focus is the best I heard sofar. Instruments and voices are that much better separated and easier to point out. Most of the people who hear it say the same words; We never heard this level in touchable presence. I see you use the XP-20, which I used for 2 years. In the last few years I owned many different Pass labs power amps. I can crush a XP-20 with a Onkyo PR-SC5509 with my Pro measurement. I also invited Pass Labs wenn then are in Holland to come to me with a XP-20. I measure totally different what Audyssey does. I played for about half a metre beside the speakers with the XP-20. Now I play even wider. The biggest difference what I can make it that voices and instruments are better focussed and also there is more articulation of voices compared to the XP-20. I use recordings so it is more easy to understand for people. For example: Bruce Springsteen's Brothers under the bridge. The endings of his words are so open and clear that people are amazed how big the difference is. I can put all the different parts of the Audyssey settings to on and off. Roomcorrection is only 1/3 of the whole system. Wenn I compare the Audyssey way and my way of measurement; there is a lot more dynamics, more resolution, better separation and a better articulation. With my way of measurment the needle of a Pass amp starts to move only at extreme high volums. With my XP-20 it started much earlier. Audioquest makes my new level in sound even better. Would be nice to test the newest Audioquest cables and compare with the new Transparent cables.
Bo, Was the system at that show identical to your system? If not, how can you be sure that what you heard is attributable to the cables?
Bo1972: That makes sense.
Yes it was identical, I only used the Pl-100 instead of the GXFX speakers. I used only Purist Audio LE 2013 powercables. For the rest it is identical. Audyssey EQ and Volume and my way of measurment gives me more dynamics and a far better articulation of info what is on a recording. But without the Audioquest the level in blacks is a lot lower. This is very important to make the 3-dimensional stage this thrilling. At the end you hear to all the parts. They are all important to get this level. Every tool ( speaker, amp, source, cable etc) I test I want to know which talents/properties it has. It is my goal to get all of the talents out of it. So I need and use other tools to get this level.
I the last months I sold many Onkyo PR-SC5509 with my measurment to clients who had much more expensive pre-amps. Because the level I can get out of there sets is that much higher. Without this measurment it is worth a lot less. For example the tripod and the tool for the microphone Audyssey delivers is useless. I use all the knowledge I have gathered in the 15 years that I do this work.
Bo1972: With the Onkyo being a mutichannel home theater unit, are you able to run that in 2 channel only?
I have stunning results in both 2 channel and Multi channel. I use it and sell it both in stereo and in Multi channel. I prefer it over the XP-20 from Pass Labs even in stereo use which I had for 2 years. I talked about this several times with Pass Labs. My stage is even deeper and wider than I had with the XP-20. The Onkyo with Audyssey Pro has a more sharp individual focus of instruments and voices. But that is not even the most surprising part. 2nd and 3th voices on recordings are a lot more easy to follow. Because the articulation is better. I never heard 2nd and 3 th voices this clear. It is the same with instruments. For every person it is that easy to focus on every single part of the recording.
Bo1972: Thanks for the info. Very interesting that it beats the XP-20. It's also a lot less expensive! How's the phono section on the Onkyo?
No the phono section is not that special. You have to hear it how unique the Onkyo PR-SC5509 with my measurement is. Because I would not believe wenn someone would say this story. I would say it is the biggest bullshit I ever heard. I understand that it is difficult to believe. I have plans to modify the Onkyo with better parts later this year. The person who does my technical support is exeptional good in technique. He modified many expensive amp's and sources from clients. I think we can reach even a higher level.
Ok, cool, sounds good. Good luck with that. Speaking of Onkyo, why not this preamp from them?

http://us.onkyo.com/Products/model.php?m=P-3000R&class=Reference&source=prodClass
I did use this one also a little at the show. I tested it also at home. It is good, but it is not exciting. Without Audyssey Pro you stay in a different world. During the show I used my Samsung Plasma ( 64 inch) as a screen. I can put the different parts of the Audyssey system to on and off. Wenn I do not use anything of Audussey anymore the party is over. Drive, speed, sublime focus, dynamics and resolution are lost for a very big part. With the XP-20 I had very good results in dynamics, focus, resolution and in a wide and deep stage. But now every part with the way I measure I can top all of it. I learned to use Audyssey from a highend perspective. Audyssey is focussed on a different way. Those results are good sometimes but never thrilling. The way they use it you still loose too much. This part I did improve a lot. Wenn you build a surround system you first start with the stereo part. From stereo you build to Multi channel. The reason is very simple. Wenn every part in stereo is right it is easier to get it right in Multi channel. I have a lot of music on bluray these days and I love it. But I still play the most in stereo.
Ok, cool, sounds good. Audyssey sounds interesting. Thanks for the recommendation.