Some of you may know that I have some buzz/hum issue in one of newly received XA60.5 mono blocks. The dealer diagnosed the problem and determined the transformer needs replacing. Since the XA60.5 is only few days old so I am given the chance to get a replacement set or I could top up the price difference to get the X350.5 or XA100.5s when my dealer gets their stocks in the next 3-4 weeks time.
Kudos to Pass Labs and the dealer's service for all the patience and after sales services...certainly very much appreciated and glad I go for Pass Labs.
As such, I have 3-4 weeks to listen to the current XA60.5 in my system while waiting for the stocks to arrive and make the final decision on the swap/upgrade.
I owned them both in the past. The difference in sound and more in authority is clear. The overwhole sound of the 100.5 was a lot better. The same about the stage and the extra authority. I found the difference bigger than I thought it would be. That time I used it with the XP-20.
I use a pair of XA-100.5s with my Vandy 5As in a 14 by 24ft room. The meters on the XA-100.5s rarely move (leaving class A) unless I am playing fairly loud (above average 90dB) or listening to something with quite a bit of dynamic range (symphonic music) -- in either case on peaks above 98-100dB. My listening position is about 12-14 feet back from the plane of the speaker baffles.
I originally purchased a pair of XA-60.5s for my system after running a pair of ModWright KWA-150s in bridged mode on high bias. I really liked the tone of the ModWrights and thought I'd like to try full class A. Given that the 5As have powered woofers, I thought that the XA-60.5s would be sufficient for my system, room, and listening habits, but I found them swinging out of class A (moving meters) more than I liked. So I traded up to a pair of XA-100.5s and have been very, very happy. That said, if I find myself with extra cash lying around after upgrading my front end and preamp, I would love to have a pair of XA-160.5s just because.
Based on my experience, I think the XA-100.5s would be more than adequate in your situation.
Has anyone tried either the XA60.5 or the XA100.5 with the Vandersteen 5A? I'm wondering if either Pass amp has enough power for medium sized room and moderate listening levels (@10 ft).
Light: 'More power means more complex circuit' is not necessarily true for Pass amps. I've seen an amp on his DIY site, which you can adjust output power of simply by continuing to parallel output devices. Of course, some additional changes need be made, perhaps a higher VA rating on the main transformer and a higher current bias power supply. More devices DOES mean an additional opportunity for component failure, but SS devices ran within normal parameters have a very high MTBF. I'd bet as much as 20 Pesos that the higher power amp is at least 98% as rellable as the lower powered version....other things being equal.
I heard it said that the XA30.5 and the X150.5 are the SAME amp, save for some bias circuitry adjustments. I'm not sure, but it is feasible, I suppose. Though, if it were ME making these amps, I'd have an A-A/B switch so you could CHOOSE the mode which suited you or your mood.
Good news about the 3.7s and fuses. Ribbon fuse veterans of Magnepan refer to the Ribbon as the 'fuse protector'. Pretty fragile when presented with hi current distortion. Depending on the low / mid crossover point, the entire panel may be capable of sinking 12 amps...perhaps 50% more than the 1.6 with which I'm most familiar. My ancient MG-1 fuse was a paltry 1.5 amps above an unknown crossover. Based on the current capability and advertised sensitivity, even with all the stuff I said.....above.....I'd never try the 30.5, but go to at least the 100.5s......
Light, Maggies are generally not a bad load for a good amp like Pass. IF the new 3.7s follow Magnepan pattern, there should be NO impedance dips to weird lows OR any huge phase angle stuff to deal with. OTOH, they ARE fairly low sensitivity which is made up for by being dipole. Damping factor? Anything over maybe 20 will be fine. Even low damping tube amps work well, if enough power. The air damps the mylar pretty well, and being a single sided driver, not as coupled to the magnets as a good cone driver. The push/pull 20.1 may be slightly different. You are right about dynamics and power, though...
Power users of panels like some of the big 'd' offerings. Spectron? massive.
Also, if Pass amps thru the line are anything like the XA 30.5, while it is 30x2 into 8, pure class 'a', the redline is almost 200x2into 4 in a/b. If the XA 60 does the same thing, it should be quite sufficient. Whoever said to look at the meter had it right. If the bias stays in 'a', or just a flicker periodically or on crescendos, than that is probably enough juice.
Given my listening habits (important for all to consider) I'd probably be quite happy with the XA30.5 level amp. The 60? WOW! OR if I had really deep pockets, a pair of 30s, as biamp!
Are the 3.7s fused? My 1.6s have a 4amp mid/tweet. I doubt the whole panel draws 8 amps at the limit. Thats just over 250 watts RMS..... How would that work out for dynamic power? Lots, I suspect.
In terms of the more power means more complex circuit with more stuff going on, so less good sound, that was certainly born our with the original Pass Amps, where the Aleph 3 was considered the best sounding, although very low on watts.
I'm going to be moving from an Aleph 5 to XA60.5 (I think) soon - I have Maggie 3.6s, so very hard to drive and damping factor means a lot in my case. I'm tempted to actively bi-amp and use Spectral or NuForce on low end. (Crossover is 225 Hz on Maggie 3.6), that is the only reason I'm not sure if I'm getting the XA60.5s. So, even if I'm still underpowered, it should be a massive difference from the Aleph 5, the XA60.5s have sooo many more Volts and Amps.
Overall I think I agree that a smaller Amp - *if* you have met your dynamic requirement - will sound better. In my case Maggie 3.6s seem to take any amount of power and still want more, so I am considering X350.5s too, and that might actually sound better in my case. Really take control of the bass panel...
Okay - this is my main comment. Add a Supratek or Joule-Electra pre-amp. With the rest of your system as it is, you'll be shocked by what happens! And then you will really have a system that plays with the big-boys :). I think it will be completely different than what you hear now.
I agree with Onemug. Somehow, the XA200.5 sounds sweet, delicate, and holographic in addition to all the other things we associate with ample power. I suspect most other solid state amps sound hard and flat as a result of their more complex design.
Nice comments Pubul57 and onemug. I believe you need the appropriate power to match the needs of a given speaker. I`ve personally have never been convinced by the arguement for gratuitous power i.e. one can never have too much power.
I`ve experienced enough examples where a lower power amplifier of equal built quality but simpler design and fewer parts(less complex) just sounds better(as long as the speaker is suitably efficient).
The man is on of the greats, and owning most any amp he has had a hand in is a pretty good thing. Loved his short-lived 25 watt, Aleph J which should be great with most any 89-90db or higher and smooth impedanced speaker, maybe as good as the XA30.5 with my speakers and very easy to drive with a tube preamp (240kohm input impedance).
I too have found that smaller wattage amps will generally have a sweeter/purer sound. In decision making, I always go by my ears first then work backwards with my brain to see if there is a reason for a finding, but always ears first as they are "direct coupled" to my wallet.
This has held up even with my sub-hobby of vintage receivers. I prefer the sound of the lower watt ones to the monsters of old. What I have read (but don't know first hand) is that a lot of "music lovers" prefer the sound of the Marantz 8b to the 9's and the Mac 225 to the 275. Of course the speaker, and how loud you like it, are important factors.
I have a hunch one reason might be transistors and their non-linear characteristics. The more of them you use, the more NFB you need to get the amp to "spec" right. I personally don't like NFB.
My ears like what they hear in Pass's XA.5 series and this is from a guy who loves/has 4 SET amps. I have their 30.5 and 100.5's. Don't hear much difference beween the two. From what I've read about the design, running the Mosfets in pure class A, he can put them in their most linear range and therefore use much less feedback to correct. In his paper on the "Super Symmetry" circuit, he says he uses only a tiny bit of NFB to tweak the two circuits into balance so they cancel distortion. This may be why "his" larger amps don't lose don't lose the sweetness like other designs do. His papers on the Passlabs website are a good read.
I still believe the monoblock argument about separation, though it may be an article of faith as some folks I respect on things audio don't believe this is the case with well made gear, I don't know but there certainly is very highly regarded gear in stereo configuration - and my Music Reference RM9 and CAT JL2 had pretty darn good separation:) The theory certainly makes sense, and it must be an advantage to be able to run shorter speaker cables.
Good point Pubul57. I've never tried my bigger XA.5 amps with more efficient speakers, so I really don't know if they sound better or worse than say the XA30.5 would. I would expect some advantage from monoblocks with the separation of each channel, but that is also just speculation on my part.
I would expect all those benefits when you move from an underpowered amp for one with the power necessary to drive a given speaker. But I'm not sure how you know there is no sonic price driving a speaker that can easily be driven by an XA30.5 and then driven by the 160.5 - let's say a speaker with 94db sensitivity - I suspect, but cannot prove it since I have not tried it, that there is a sonic price to be paid for those extra watts, when those extra watts serve no real world purpose in being able to drive the speaker loud and with bass control.
In your case the sonic penalty is paid when trying to drive a speaker that needs more power than you had with the XA100.5, and when you need more power I would not expect a sonic price being paid by adding the higher powered amp, it is the wattage you need to make the speaker come alive and a lack of power is a much higher price to pay than a lessening of purity due to all the added electronics need for higher output..
However, at any power level, I think the XA.5 series is among the best sounding SS amps available - they are all excellent IMHO. The changes you can expect in moving from the 60 watt version and 100 watt version will depend on the speaker being driven,
I enjoyed the XA100.5 very much until I bought a new pair of inefficient speakers and found the amps did not have quite the power the speakers needed. So I traded the amps in for a pair of XA160.5's. The result was a more open and effortless sound with a slight increase in soundstage depth and clarity. Bass also had more impact with slightly more control. There were no areas in which the sound got worse. But they are heavier and hotter, take up more space and use more energy.
Perhaps the 10.5 is the sweet spot, but if one needs more power, I'd recommend as much class A power as one can afford. There does not seem to be a sonic price as you go up the XA.5 line.
"Overall, the music picture portrayed by the 100.5 is towards a denser and complete sound if compared with the 60.5.
If one can stretch, go for the 100.5. I agree from some of the comments I read and heard, the 100.5 is the sweet spot model among the XA.5 series in Pass Labs."
"always craving for even more resolution, more speed and a tighter and more defined low ends...design and characteristic of Pass Labs sounding slightly layback"
Interesting, because that is not what I experience. Not doubting what you hear or your musical preferences because you've done the comparison. But, I hear natural and flowing music. Pace, detail, staging, and lower end are just right.
Apologies for the late update, was tied up and seldom log into the site.
Yes, I've upgraded to the XA100.5 and used the same VSA Unifield 2s on the 100.5 and 60.5.
What I felt from different amps on the same speaker, the 100.5 sure have more headroom, and sounds less congested when playing heavy tracks(classical and live rock concert). The beautiful mids are similar to the 60.5 but do feel there's slightly more definition and resolution with the 100.5 on the mids and highs hence the soundstage sounds more focus. Some increase in width and height on the soundstage too.
Overall, the music picture portrayed by the 100.5 is towards a denser and complete sound if compared with the 60.5.
The 60.5 is a great amp, but with higher Pure Class A watts using the same design does better it and it should being a higher cost model.
If one can stretch, go for the 100.5. I agree from some of the comments I read and heard, the 100.5 is the sweet spot model among the XA.5 series in Pass Labs.
Now as they say, nothing is perfect. Coming to the down side of 100.5, I am always craving for even more resolution, more speed and a tighter and more defined low ends from them especially when I am listening for live music concerts on classical or rock. Believe this is the design and characteristic of Pass Labs sounding slightly layback with benefit of a more beautiful mids and highs.
I have since moved on and am very happy what I can achieve with the Soulutions.
7p62mm: "A couple of advantages that the XA60.5 has over the XA100.5 is the 33% lower up front cost and the 33% lower power consumption (200W versus 300W)."
And in my experience, lower power versions of the same circuit generally sound better than those requiring more complex output stages for the additional power - IF you have sufficient power. With 90db speakers, 60 watts 8 ohm should be more than enough, unless you really like the idea of premature hearing loss or the ability to make you neighbors want to move or sue you.
I owned the 350.5 and the 250.5 at the same time, and for me in my system the 250.5 was the winner. It simply had better synergy equally from top to bottom. The 350.5 was leaning more to the upper frquencies and not as balanced as the 250.5
My friend also had the 250.5 and bought the xa 60's. We pretty much have the same system, and to me the xa 60 were to liniar not as much weight and body as the 250.5. Some what like the 350.5.
I here the xa 100's are more full bodied like the 250.5
My speakers are 90 db efficiency. My amplifier provides 400+ watts into 4 ohms. I use every one of those watts, every day. And not just for a couple seconds.
I am curious as to which amp you chose. Assuming that your speakers have a 90dB efficiency rating. You would only need about 1 Watt/channel to drive them to around 80dB at 3 meters so the XA60.5 should provide all the power that you need. See the following link for power calculations: (www.myhometheater.homestead.com/splcalculator.html)
The advantage to Class A is that there is no distortion due to cross over from A to AB operation so operating at low power output levels won't be an issue. A couple of advantages that the XA60.5 has over the XA100.5 is the 33% lower up front cost and the 33% lower power consumption (200W versus 300W).
Just an update, finally my long wait for the XA100.5 ends 2 days ago.
Have it delivered, setup and running in my room. Played for first 3 hours and already noticed the benefits of having more headroom even if its not required.
Cannot wait to run them in another 100hrs before giving further views against what i had previously experienced with the XA60.5.
Can you believe I am still waiting for the stock of Pass labs amps to arrive my local distributor. It's been close to 3 months in about a weeks time. Would love to give you some views of the jump from the xa60.5 to xa100.5 which I intends to do.
Still waiting anxiously.... The dealer says the shipment is on the water and I got that since 1 month ago and still avail.
Will definitely update my views of the sound when I have the xa100.5 settled my small audio room.
If the amp is going back to Pass for repair anyway, perhaps you could just contact Mark @ Reno to set up an audition of the XA100.5 and the X350.5. I'm sure Pass and Reno could work out an accommodation as customer service is a top priority for them.
Scratch that, I just noticed you are in Singapore. The dealer should let you audition. If not, contact Pass and find another dealer. Should should hear the difference for yourself.
If I were you I would contact Pass Labs directly and talk to them about your dealer. I think it's ridiculous that you cannot audition these amplifiers. You're a proven customer. Does your dealer really expect people, particularly people who have shown that they are real buyers, to buy $10k plus equipment without seeing and hearing the product? It's even more outrageous that you're being so terribly disrespected after receiving a defective product. There's no way you should tolerate being treated so poorly!
Alternatively, for the price of the items you're considering the cost of a plane ticket to a dealer who has the items in stock and allows potential buyers to audition is not all that significant.
A couple thought to consider, since you have a few weeks before you need to make a decision.
If the amps are brand new, they're maybe still breaking in. The sound will be a little more vivid after they are fully broken in. Make sure they ARE broken in ASAP so you're really hearing them properly.
Also, your speaker/listening positions, dacron stuffing, etc. are still probably what you found worked best with your prior amp. You might be able to get what you want for free just by going through that process again.
In the same vein, try a few other cables if you can during the next couple weeks, since it sounds like you're already pretty close to what you want, and you might feel compelled to do this anyway once you've got the amplifier thing settled.
I must have misunderstood you. I thought from your original post that the dealer is getting new stock (both the X350.5 and the XA100.5) in the next 3-4 weeks. I assumed you would simply be able to listen and compare them to your XA60.5 at the shop or better in your system. Now it seems that these will not be available to you to demo/audition in your own system. Is that the purpose of this thread? The dealer will have these for you to purchase, but you will not be able to listen to each ahead of time? That is the only way to really know for yourself.
I agree with Jpspock. The pre amp makes a big difference and the Pass units sound great with the Pass amps. Have you considered getting a preamp and just repairing the XA60.5 instead of upgrading the amp? I would ask Pass or the dealer if this makes more sense.
Peter
1) I have always benefitted from more power with my Pass amps. Enough power to drive a given speaker to certain SPL is one thing, for the speaker to sound it's best is often another. For me, the XA160.5 sounds considerably better driving my Mini II's (87dB, 4 ohm) than did my XA100.5. Elmerpoh may prefer the sound of the XA100.5 to the XA60.5 even if it seems like the added power is not needed.
2) Elmerpoh may benefit more from a Pass pre amp with his existing XA60.5 than with the XA100.5 and using his DAC directly for roughly the same money.
3) The only way to be really sure which amp he will prefer is to listen to the X350.5 and the XA100.5 in his own system if this is possible. The dealer may not allow this. It is unclear.
I have always bought the biggest Class A Pass amp I could afford at the time, and with my speakers, Eggleston and Magico, the sound has benefitted.
Hi Peter, I am unable to have any head to head hearing of the XA60.5,XA100.5 and X350.5 as my dealer does not allow unsold open boxes. I do agree that pre amp can makes a some difference of the sound amplified out to the speakers. Was told there are 2 school of thoughts on pre amp; 1)If I do not have more than 1 source, maybe better to connect the DAC directly to the power amp since the DAC has decent pre amp qualities. 2)Adding a pre amp to give the finishing touch of sound before its being amplified by the power amp to the speakers.
Point 2 actually make me think whether using a decent Tube Pre with the X350.5 makes the sonic qualities compare with the XA.5 series(especially lush/bodied/liquid mids and highs).
I agree with the point 1 & 2 you made. Does agree that 120w @ 4ohms is sufficient for my speakers in my room, just trying to establish whehther what improvement I can expect by going from XA60.5 to XA100.5 with all else being unchange. Point 3 is something which I am trying to get views from someone which has heard them before since i am unable to do.
So far I can gather the following choice given unable to hear them side by side:
1) Get a replacement set or repair the XA60.5(which i am not happy with the bottom end sonics), maybe add a pre to the XA60.5 to seek better sonics on the lows. 2)Swap for the X350.5 and match with a decent tube preamp to touch up the mids/highs. 3)Swap the XA60.5 with XA100.5 and get a Pass pre amp at later stage.
I bought a pair of XA160.5's based on a combination of auditioning an XA30.5, advice from Aerial about 20T's power requirements, reading about Peterayer's experience, and this commentary from an email to Pass, which might help a little. You might want to email them about your specific circumstances.
I am very happy with the XA160.5's by the way. You should know that the XA100.5's will heat your room about 50% more than the XA60.5's - I would estimate 1,400 btu/hr for the pair. The extra ~500 btu's are unlikely to matter much if you have ample air conditioning - it's like having two more people sitting in the room.
>> >> The XA30.5 is very much a good indication of the XA line both for >> spectral balance and detail. As you move to the larger pieces you get >> "more" of what the XA-30.5 already is. >> >> The exception if there is such a thing would be the XA60.5's. They are >> more dynamic and powerful as one would expect, but their character is >> very slighlty warmer than the XA30.5 and XA100.5 at low to moderate >> listening levels >> >> The XA100.5's are very similar in character to the XA30.5 but by virtue >> of their ability to drive any load we can imagine, pretty much set the >> standard for dynamic contrast and focus of image.
>> Best >> Kent English / North American Sales >> Pass Laboratories >>
I think the XA60.5 should have enough power for Elmerpoh to enjoy his system. I've tried (unsuccessfully I guess) to make three points in this thread.
1) I have always benefitted from more power with my Pass amps. Enough power to drive a given speaker to certain SPL is one thing, for the speaker to sound it's best is often another. For me, the XA160.5 sounds considerably better driving my Mini II's (87dB, 4 ohm) than did my XA100.5. Elmerpoh may prefer the sound of the XA100.5 to the XA60.5 even if it seems like the added power is not needed.
2) Elmerpoh may benefit more from a Pass pre amp with his existing XA60.5 than with the XA100.5 and using his DAC directly for roughly the same money.
3) The only way to be really sure which amp he will prefer is to listen to the X350.5 and the XA100.5 in his own system if this is possible. The dealer may not allow this. It is unclear.
I have always bought the biggest Class A Pass amp I could afford at the time, and with my speakers, Eggleston and Magico, the sound has benefitted.
A little late to the discussion here. I use XA-30.5 to drive my speakers with 91dB/w sensitivity and presents 4 Ohm load under 1KHz. I listen to music fairly loud, louder than most of my friends. Even that loud level is only around 80dB at the listening position - average. The musical peaks can reach 90dB and up. As to how the dB figures translate to the real world, at 80dB it is somewhat difficult to carry out conversation without significantly raising the voice. At 90dB you would be shouting to each other and barely hear them. Most my friends listen at 65-75dB on average. I assume that's the same for vast majority of audiophiles.
What that means is most people don't _need_ that much power in reality, unless the speakers are extremely inefficient or difficult to drive. But it's like owning a car. Most people don't need 500HP engine but we all want to.
Nelson Pass wrote about what it really means for an amp to transition from class A bias to class A/B bias. That's when the needle starts to move for Pass amps. The needle moving past the stationary position is not an indicator of the amp running out of capacity. The maximum power for XA-.5 amps are published elsewhere, and they are significantly higher than what the model number suggests. The maximum power is of course delivered in class A/B mode. Then the question is will someone be able to discern the "quality" of power delivered in class A mode vs class A/B mode of the same amp. That's a good question, but it's of no concern for me any more. The needle on the face plate jumping up and down was maybe a little bit entertaining in the beginning, for example during the canon fire of Tchaikovsky's 1812. But I came to the conclusion that my amp has plenty of power for me, and nothing good will come out with worrying about the class A vs A/B currents and needle movements. That way you tend to enjoy the music more.
I must have misunderstood you. I thought from your original post that the dealer is getting new stock (both the X350.5 and the XA100.5) in the next 3-4 weeks. I assumed you would simply be able to listen and compare them to your XA60.5 at the shop or better in your system. Now it seems that these will not be available to you to demo/audition in your own system. Is that the purpose of this thread? The dealer will have these for you to purchase, but you will not be able to listen to each ahead of time? That is the only way to really know for yourself.
I agree with Jpspock. The pre amp makes a big difference and the Pass units sound great with the Pass amps. Have you considered getting a preamp and just repairing the XA60.5 instead of upgrading the amp? I would ask Pass or the dealer if this makes more sense.
I listened the XA60 and 100.5 the same day on the same Sasha. I compared the X350.5 with 250.5, 600.5 on Sophia2 and the on WP8. One thing is very important too : the preamp. I have compared the XP10 and XP20 with XA100.5 and X600.5 and XP20 is much better : wider and deeper image, deeper and articulate bass, magnificient midrange. So when you will listen to those gears, don't forget the impact of the preamp, because it can change everything.
Yup, I would think XA100.5 or higher, but those 100s are conervatively rated, might do the trick with the Sashas, but it does seem to be one of those speakers like some Thiels and B&W were the more power the better - they need it.
07-13-10: Onhwy61 If I understand your situation correctly you will have the opportunity to listen to both amplifiers. You will have a better chance of making a good decision if you listen to each one without expectations of what they will or won't do. Listening without preconceptions is a good thing.
07-13-10: Pubul57 I would expect the XA-100.5 to be "better" than the XA60.5 with the WP Sasha, that amp/speaker combo is better suited to the needs of the WP. But, as Onhwy61 points out, listening is worth 10,000 threads on the topic (now if you can only get rid of preconceptions during the listening - hard to do sometimes).
Hi Onhwy/Pubul,
My local dealer unfortunately does not have the XA100.5 or X350.5 in demo to listen/audit. I was even unable to hear XA60.5 before commiting. However prior putting my cash down, I was able to audit the X260.5(mono blocks) and XA30.5 on Sonus Faber Auditor M as the dealer is also a Sonus dealer. I like the mids and highs on the XA.5 but the XA30.5 lows was abit loose and not as articulate sounding as the X260.5. Thinking the XA60.5 monoblocks should better that concern and XA60.5 in my room indeed does better than what i heard on XA30.5 at the dealer's premises.
If not issue in one of the XA60.5's transformer,I would not be given the chance to change/upgrade models. Maybe sometime chance of choices are not that good afterall.
07-13-10: Jpspock I own a XA100.5 with WP Sasha. Before buying tha XA100.5, I compared it with a XA60.5 that is a very great amp. The difference between both is the bass are far better articulate,with XA100.5. I compared the XA100.5 with the X350.5, and I prefered the XA60 because it's much more musical, you feel more involved into the music. So if you do not need the power of the XA100, go to XA60.5.
Hi Jpspock, For my info, did you manage to try the XA100.5 and XA60.5 on the same WP Sasha? Was the comparison on the XA60.5 and X350.5 on the same speakers as well? Fully agree that the XA.5 has more magical high and mids than the X.5, that was what i felt when i hear the X260.5 and XA30.5 both on the Sonus Faber Auditor M.
I would expect the XA-100.5 to be "better" than the XA60.5 with the WP Sasha, that amp/speaker combo is better suited to the needs of the WP. But, as Onhwy61 points out, listening is worth 10,000 threads on the topic (now if you can only get rid of preconceptions during the listening - hard to do sometimes).
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