Pass Labs:What to expect fm XA60.5 to XA100.5


Hi Guys,

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.
elmerpoh
Does the meter on the XA60.5 bump around alot? If it moves on more than an occasion, go with the bigger amps.

Your description of the sound of Rock and Concertos with the XA60.5 does sound like a potential power issue.
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Hi Guys,

Thank you for all the inputs.


Pubul57
With your speakers I would not expect much of a difference going from the XA-60.5 to the 100.5, it just doesn't seem like power (a fairly marginal difference here) is the issue, not with your speakers and your room. Did you ask Pass Labs?

07-12-10: Pubul57
Though I did not say it before, I should have added that IMHO the XA60.5 will sound as good, if not better than the XA100.5 IF it provides enough power to drive your speakers to the volume levels you want, and in the case of your speakers, that would seem to be the case. All things being equal, my opinion is that the same basic circuit design sounds better in a lower watt configuration than higher watt because it is a simpler device at lower watts. My general rule is buy as many watts as you need, but no more than you need.

Hi Paubl,
As my speakers are in 4 ohms, the difference in terms of Pure Class A wattages powering are 120watts@4ohms for XA60.5 and 200watts@4ohms for the XA100.5, in addition the XA100.5 has a damping factor of 200 instead of 150 in the XA60.5 and X350.5. Not too sure if increase of 50units damping factor will be a big improvement effect to the speaker I am using. The Unifield 2s are 91db/1m @ 4ohms min. Pass Labs advised if I want an amp able to run most if not all speakers in a mid to large room and to keep it for a long long time to come, it would be the XA100.5.
I was always told all speakers like wattages, the higher the better.


07-12-10: Tvad
Are you running balanced or single ended from the Bel Canto DAC to the XA-60.5?

The Bel Canto DAC outputs 2.5Vrms single ended and 5.5Vrms balanced. If you're running single ended it's *possible* dynamics are being affected, and you might try running balanced instead.
At the volume levels you normally listen, there will be no discernible difference between the XA-60.5 and XA-100.5, IMO. At 98dB peaks, you're only using 8 watts of power.

Hi Tvad,

I am connecting using balanced outputs from the Bel Canto DAC. I am thinking if the higher wattage(120w vs 200w @ 4ohms),higher damping factor(150 vs 200)higher output Voltage(32 vs 41) and higher output Amps(20 vs. 28) will bridge the gap on dynamism, speed/explosive transient between the XA.5 and Class Ds.


07-12-10: Peterayer
I went from the XA100.5 to the XA160.5. My speakers are a very demanding load and I thought I would need more power/current. I first demoed my speakers with the XA30.5 and they sounded a bit restricted during loud classical passages. My XA100.5 was better so I considered the XA160.5. I called Kent at Pass and he said I would get a bit more of everything. He was right. Better dynamics, larger soundstage, more effortlessness, better air, better control of bass. All this in a small room at moderate volume 75-90 dB. Music just became more involving. The improvement was not huge, but better in every way. For me, it was definitely worth the upgrade cost.

I am not familiar with your speakers and have not heard the XA60.5. I suggest you contact Pass Labs and describe your situation. I also have not heard the X350.5, but if you like the pure Class A sound and the XA100.5 is enough for you, it might just be the ticket.

Hi Peterayer,
I have enjoyed your review of the XA100.5 very much think its hard to improve the experience. The higher level models of the XA.5 must be really something.Cannot imagine what the XA200.5 could provide. For me XA100.5 is the furthest I could stretch. Not sure if the benefits of X350.5 on dynamism, speed/explosive transient,high Class AB 700watts @4ohm will make me forget the smooth liquid mid/high of the XA.5 Class A power. No best of 2 worlds as one would say I guess.


07-12-10: Rtn1
Does the meter on the XA60.5 bump around alot? If it moves on more than an occasion, go with the bigger amps.

Your description of the sound of Rock and Concertos with the XA60.5 does sound like a potential power issue.

Hi Rtn1,
The meter does bump/swing slightly when i am playing rock and concertos at about 80db volume, but it does not pass the 12 o'clock mark.


Elmerpoh, how far from the speakers do you sit? Is this the distance from which you measure your listening volume?

If so, measure again from your listening position, and then move to 1 meter from one of the speakers, measure this volume and report it here. Try to measure a loud music peak. Be sure to point your decibel meter at one speaker or the other...not down the center.

Hi Tvad,

I am sitting at the sweet spot location which is about 2.2meters away from the left and right speaker.
I am only taking the listening volume from the volume level shown on my Bel Canto DAC acting as pre amp.

At the moment i do not have a SPL meter, will try to find one to do some measurements.

Cheers
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Elmerpoh,

Given your 91dB and 4 ohm min impedance and the fact that you listen fairly close to your speakers, I would think that the XA100.5 would be plenty of power and the X350.5 might be overkill without as much Class A magic.

I would enjoy the XA60.5 until your dealer gets the new amps in. Then, just audition each one in your own system and decide which you like better. I think it will be the XA100.5 over the X350.5. Remember, they need to be on for a few hundred hours to break in, at least mine did. Then, just enjoy the pure, glorious sound.