Review: Pass Labs XA60.5 Monoblocks Amplifier

Category: Amplifiers

The Pass XA60.5 Monoblock Amplifiers

I had been running the Pass XA30.5 Stereo Amplifier for about the last year with this System: Tyler Acoustics Decade D1 Loudspeakers, Ayon CD-2S CD Player, Jeff Rowland Capri Pre-Amp. The Tyler Acoustics D1 Loudspeakers are 8 ohm and are fairly efficient and the Pass XA30.5 did a wonderful job driving them. The sound of the XA30.5 is something special for a solid state amp. I would define it as very smooth from the highs to the bass and the mid-range is what distinguished it in my mind. The voices seem to be right there in front of me with so much realism and feel that it seemed the musicians were there in my listening room (also my living room). Well, I made a change from the Tyler Acoustics Decade D1's to the Tyler Acoustics Woodmeres. The Woodmeres are four ohm loudspeakers and they each have two seas 10 inch bass drivers. They may have similar sensitivities to the Decades but they are a larger load to push. I found that the Pass XA30.5 gave me that same midrange with the Woodmeres but was lacking some punch, especially on passages that were dynamic. Then comes the big debate! How does the Pass XA30.5 Stereo Amp compare to the Pass XA60.5 Monoblocks? I made a post on Audiogon and got a wide range of responses. Some people told me that they felt that the difference of 3 db would not make that much of a difference in my system. Many people seemed to feel that putting the money into the monoblocks was not the way to go. Some other people talked about that I was underpowered for the speakers I had. Someone suggested that I think about more efficient speakers. Anyway, I got a variety of responses.

The Real World:
The real world answer that that you don't know how anything is going to sound until you hear it. We can speculate all we want about how we think a particular component is going to effect our systems but until you hear it, you really don't know. I have said it many times but the biggest issues in most systems are the rooms the systems are in and the secondary issue is the synergy or lack of between the various components. I have been down the path myself many times worrying about how a cable change would effect the system. Well, the cable changes don't effect the system anywhere near the level that the loudspeakers, the amplification, the pre-am, and the source. And my room makes a big difference in what type of sound I can achieve. Well, I am getting off the track which is why I don't typically write reviews but lets talk about how the Pass XA60.5 Monoblocks effected my system. In two words, MAJOR CHANGE. The Woodmeres are being driven in a totally different way. The sound is effected whether I am playing the system at low, mid, or high volumes. My sound with the Pass XA60.5 Monos has all of the great qualities that the 30.5 stereo amp offers and much more in addition. Here is what I get. I get a much fuller, richer sound (much more weight to the sound). I get an even greater realism to the performances of the artists. The dynamics to the sound is dramatically different . The pacing seems different and the system is delivering a much bigger sound. Bigger is not just louder but more importantly, is that sense of involvement and engagement with the music whether it is the highs, the midrange, or the fantastic bass response. In my system in my room, the monoblocks just electrify me so much more than the stereo amp. The bass response is much tighter as the drivers are being controlled in a much different way. Having separate power supplies to each speaker makes a big difference in my system. I spent a tremendous number of hours listening this weekend and keep coming back to how wonderful the music sounds. By the way, having a terrific dealer like Mark at Reno HiFi makes a big difference as I was able to try the Pass XA60.5 Monoblocks and compare them to my Pass XA30.5 Stereo Amp and either buy the monoblocks or send them back to Mark and keep my stereo amp. Mark, unlike many dealers I have worked with in the past, is willing to have as many conversations about the products all through the various steps of a purchase and is someone who is honest and very easy to work with. You never feel guilty calling and having as many conversations as you want about a product. Thats just the way it is with Mark.

I think the Pass XA60.5 Monoblock Amplifiers are terrific and are probably the best solid state amps I have owned. They have so many outsstanding qualities but on a simple level, they deliver the music in a very engaging way that makes you want to get out of your seat. The amps present the music in a very natural way that both includes a seductive midrange combined with excellent dynamics. I can listen for hours.

Sorry, if I rambled to much but speculating how a particular component is going to sound in anyones system is very hard to do and it is best to try try to hear a product before you make a judgement to purchase it. Audiogon thoughts and opinions are wonderful and we are lucky to have such a great forum to express our thoughts but in the end, your ears will determine how something works or does not work in your system. It is a trial and error and certain components work better with other components than others and all components are most effected by the room in the end and that is our biggest challenge, to get the most out of the room. By the way, I am certainly no expert , just another person who enjoys music and keeps listening. These are just my thoughts and I respect other opinions as long as we treat each other with respect and allow disagreement in a constructive way. Stephen

Associated gear
Tyler Acoustics Woodmere Loudpeakers
Jeff Rowland Capri Pre-Amp
Ayon CD-2S CD Player

Similar products
Pass Labs XA30.5 Stereo Amp
Congrats on the amps! I've been enjoying mine for about 5 months now; these amps really sing!
Hi Pettyfeversk, congrats on your new XA 60.5 monoblocks! Your enjoyment of them totally comes through in your review.

When you had your thread on if the 60.5's sound better then the single chassis 30.5, I chose not to post, however I knew if you auditioned them the results would be what you finally heard with your own ears.

For fun take a look at my review here on the GON of the 60.5's that I use in my system to compare how I experience their performance compared to your impression of them.
Thanks for sharing, very interesting!
Thank you all for your kind words. Teajay, I will read your review tonight after I get home from work. You are right, I am very excited about the amps as they are adding so much to the sound of my system. If you want to say hi at some point, I can be reached by email at and can give you my cell phone number. Stephen
Hello Stephen, You took the plunge. Congratulations!
The XA30.5 Vs XA60.5 mono blocks is an interesting one.

The 30.5 draws 230 watts at all times and the 60.5 double that. I have the 30.5 and run it 24/7 at the electricity cost of $15 per month.

If you have sensitive speakers and turn the amps from standby to on, wait 1 hour, and then play music, an hour or two later you reach optimal sound quality. Left on 24/7, you can play right away and get optimal sound in 25 minutes. How often do you listen? I listen 3 Hrs per day.

Another fact is at the same volume, within the limits of the 30.5 you get a simpler circuit (half the power transistors) and a purer sound IMO, YMMV. Simpler is better, given essentially the same design, at half the cost!

Do Not let the 30 w/ch @ 8 ohms rating fool you! You actually get 60 Class A ave., 100 Class A peak, and over 200 w AB ave. into 4 Ohms! How much power you actually use for everyday listening, the type of music, room size, and speaker efficiency should give the best buy.
Don c55

Thanks for your response. I listen pretty much each night after work for about 3-4 hours and more on the weekends. I agree with you and think speaker efficiency is an important point as the previous speakers I owned before my current speakers were much easier to push and the 30.5 did it easily. It was not as easy with a bit more of a load like my current speakers. I owned the 30.5 for about a year so I was very familiar with its sound before I heard the 60.5 monoblocks. I have not found that the 30.5 delivered a purer sound. In fact, my opinion is that the 60.5 monoblocks have as pure a sound as the 30.5 but they give much more that the 30.5 could not give to my current speakers. As I stated above, I get a fuller sound and where I really hear differences are when i have the amps playing music at low to mid volumes. The bass is tighter as they take more control of the woofers and the sound is smoother and delivered with much more ease.To me, its all about the match between the amps and the speakers to achieve the best sonics.
One word evaluations like "FULLER" when comparing the many characteristics of the sound quality of music reproduction is meaningless! You give no info on your source or musical taste.

You are simply "justifying" more expensive is better. There is only a 3 db difference. A doubling of "apparent" volume requires a 6.8 db difference as studies have shown.

Every time I have compared, over time, almost identical amps of different power from the same manufacturer the smaller amp has been better at low volumes. YMMV!
Don c55

This is what I was referring to when I talked about respecting other people. Using words like "meaningless" and attempting to discredit someone is not what it is about for me. I gave my thoughts about the differences that I heard between the Pass XA30.5 and the Pass XA60.5 monoblocks. I am not trying to justify anything whether it be cost or quality of sound. If you are happy with the 30.5 and it is wonderful in your system, that is all that is important. I lose interst in Audiogon discussions when participants are trying to make a point and use negativity directed at someone elses comments. To many of these discussions head in that direction and I will not partake in that. Thank you for your thoughts and enjoy your system. Stephen
I generally agree that often the simpler and less complex component (given equal built quality) sounds superior. However I think you`re off base with your reply to Stephen. Look, he compared both amps in his system and clearly preferred the larger Pass amp. End of story. He trusted his ears which is the only way to go when direct auditioning is an option. There`s no reason to question his motive.
Pettyfeversk, Thanks for taking the time to follow-up and share your experience for the rest of the community. Don't feed the trolls. Enjoy your amp.

Thanks for your comments. I have the amps broken in at this point and I am really happy with the system. Stephen

I just read your review and found it very informative. Your pleasure with the new amps is very apparent through your writing. What you describe is actually quite similar to my experience from when I switched from the XA100.5 to the XA160.5. Like in your system, a speaker change necessitated the amp change.

As I have said a few times before, it has been my experience that the larger Pass amp within a series (Aleph or XA.5) sounds better in my system than the one just below it in power rating. This may be because my speakers have tended to be fairly inefficient. Sure, one can do calculations about room size, speaker efficiency, Class A watts, but in the end, the listening results should be all that matters.

Finally, I agree with all of your comments about Reno HiFi. Mark is a pleasure to work with.
Hi Peter,

Thanks for the response. I wrote that in the beginning of May when I made the move from the Pass XA30.5 to the PassXA.60 Monoblocks. Its interesting to see your response as just this week I upgraded to the Pass XA100.5 Monoblocks and am in the process of burning them in. They have about 70 hours on them but I have noticed many differences between the two sets of amps. I will write more on my system page once I get more hours on the new amps. What is your thought on burn in with the XA series? The 60.5 were demos and used but the new 100.5 set, I am doing all of the burn in. You have a lot of experience with Pass amps. Do you think they reach a settled in point at 100 or 200 hours or does it not make that much difference? Do you turn them off at night totally to recharge the capacitors or just let them ruin for hours. Thanks for your thoughts. Stephen
Hi Stephen,
I responded to you via email when I go your last post in my inbox. Basically, I played my XA100.5 with music on softly for about 200 hours. I noticed the most change during the first 100 hours and then some for the next 50 hours.

Congratulations on you new amps. They are wonderful.
Hi Steve,
Well done for writing was is a very enjoyable and nicely written review. It is obvious how much enjoyment you are gaining from the Pass monos, and it's nice that you chose to share your thoughts with us. It's great to see you move up to the 100.5's btw which are my pick of the current XA.5 series. They are lovely amps & i'm sure you will get a lot of enjoyment from them! Btw, I just submitted a review of my Boulder 1060 which will hopefully be up by the end of the day.
Another well done review, thank you!