Review: Pass Labs XP-10 Preamplifier

Category: Preamps

In the quest for better audio, strange turns can take place. I had the Halo JC-2 lined out, but the newest model has a theater high-pass built in, making used units not the value they once were. Parasound will add the bypass to older units, but for $500.00, making used units too expensive at 2,700.00 in my book. I then considered the Ayre K-5xeMP. This unit has the theater by-pass built-in already, and sells for about $3,250.00 before discounts. But, it has an aggravatingly limited number of inputs (4), so that idea went out the window.

I found that the PASS LABS XP-10 was referenced in some of the reviews of the JC-2 and K-5xeMP, and thought it sounded like a unit to aspire to be like. Being somewhat broke after buying Dynaudio C4II’s A used XP-10’s available for $2,700.00 to $3,500.00 depending on condition “sounded” good. The idea of a $5,250.00 dollar pre-amp for about half that used seemed like a good idea. I listen to my stuff more than look at it, so I picked up a unit with a few minor scratches for $2,700.00.

The XP-10 has a nice complement of inputs, two balanced and three unbalanced and one each on the pre outs. One of the unbalanced can be configured to theater by-pass, so that worry is addressed. Build quality is what I would call robust. Solid slabs of aluminum and quality connectors and switches abound. I can’t see any grips about the quality. The cosmetics are more matte aluminum industrial chic than the warmth of wood and shiny surfaces.

The General User Interface is as easy as it gets. You’re up and running without a complex manual in no time. You might use the manual to set-up input 5 to theater by-pass, but that’s about it. Everything else is by inspection. The switches are all electronic relay type, and click when they are activated.

The black anodized ring offset volume knob is a continuous turn variety and simply “clicks” the out put off when the 1 dB steps reach “zero” when tuned counter clock wise, much the same as the mute except it isn’t fixed like the mute function. Turning the volume knob clockwise defeats the “mute”. The volume knob is silky smooth to the touch. I LOVE the fact that this is a precision part. It talks to a separate digital circuit to change the volume, and since it “acts” like a knob, you can quickly set the unit about, if not exactly, where you want it. No pushing and holding a button as the display counts up, or down, to a preferred setting. The remote gets you right where you need to be in just a few clicks after that. For an indirect “electronic” volume knob, this system is just great. The step s could be finer, however. More on that later.

The unit has two sensitivities to drive amplifiers and such. One 10dB elevated from the “low” sensitivity standard mode. I find the 1-dB steps to be too course with my set-up. Half dB steps seem way more useful. One step is just a bit too soft, the next a bit too loud. It’s surprising what your ears can hear (or WHY would we buy all this stuff, anyway?). PASS LABS says the volume knob was made more sensitive down low to somehow appeases people playing scrabble in the next room. I say to hell with that, I paid a ton for this thing and I want to appease me using it. A finer step volume knob would be nice. My MAP-1 had 0.5 dB steps and it was excellent for sensitivity to adjustments. I could always get the porridge just right with the MAP-1.

The display is a blue fluorescent type. Some will say various displays add “noise” to the sound. The XP-10 uses a separate supply for the display, and the circuit never touches the audio. That cool looking blue color is a PAIN. The human eye does NOT like to focus well on short wavelength blue lights. We like green, and then red, in that order, for the best sensitivity. The display is smaller than necessary, so across the room sight is mostly out of the question, and the blue color doesn’t help. Up close, the display is recessed such that you can’t see the readout from an angle much above looking directly into the unit. So get used to knee bends if you don’t place the unit at eye level. Standing up. The display has a bright, medium and “off” position. The “off” is super smart on PASS LABS part. When the display is off, it will come back to life with any adjustments, and then go back out in seven seconds. For those doubters about the audio and display interfering with one another, your problem is solved…the display is really OFF when you play music. No crazy expensive display needed if you shut it off in normal play. I leave it “off” as the unit is always on, and doesn’t have a stand bye function. But with the display in “off” mode, it is essentially in standby mode.

The weapon that comes with it, I mean the remote, is a solid naked rectangular block of CNC machined aluminum. You get ONE change to toss this thing on a glass-topped coffee table. PASS LABS must have gotten a deal on the buttons which are all the exact same black BB sized bumps, so you have to memorize the locations and count up or across to find them in the dark. Most remotes have the most used button (volume) a lefty to right rocker switch that is easy to find in the dark even without a backlight. But, the buttons all work well and have a nice “click” feedback. The distance accuracy is good, and I never found I went out of its range. Pointing the remote at the ceiling still talked to the pre amp.

Now the hard part, what does it sound like? First, I don’t have the luxury of listening to ten different pre amps at home where I have a reference to something. Nope, I have the McCormack MAP-1 and the PASS LABS XP-10. The changes in a system are many, and your results will vary depending on the amp and speakers, phono stages / cartridges ETC that you use. So I’ll try to get you in the general area as best I can.

Warm up? Nope, I plugged it in a turned it on. It was what it was, and continues to be, from day one. So days of warm-up haven’t changed anything to my ears. What I did hear, immediately, playing Paul Simon’s “song book” CD, was the detail and micro dynamics of this pre amp. Some call it noise floor, or the ability of a piece of electronics to put the fine edge sounds around objects in the stage. This really adds to the realism of the overall presentation.

Imagine a picture of a bunch of squares. The MAP-1 would add a little fuzz around the boarders between all the squares. Some call this warmth. The picture would be more impressionistic in “tone”. The XP-10 sows the source more for what it is, with little color compared to the MAP-1. The edges of squares are a distinct as they are drawn. The problem with any color, is ALL the music is softened up some. The XP-10 doesn’t do this. The layers of detail are there to hear, and the quality of the Vandersteen Quatro Woods really took advantage of this attribute. Does this mean life is grand all the time? No, if the edges of the squares are jagged (old CD’s) the sound is pretty much like that, too. Some distortion of purity softens this away, but at the expense of never hearing the capability of better source material.

Bass is a strange thing. Playing the warble test tones setting up the speakers sounded as nutty as usual. The MAP-1 and XP-10 did the deed just fine but playing music is another thing all together. The MAP-1 continued it’s full bodies flowing bass. If you audition the Quatro’s with the XP-10 verses the MAP-1, you would SWEAR that the Quatro wasn’t the same speaker. The bass is that different. You “hear” the MAP-1 bass as a full flowing “sound”. The XP-10 strips away the overall warmth, and replaces it with more of the sound of the source material only. The bass become much more controlled, tight, and layered in tonal pitch. You “feel” the bass as much as hear it deep in your chest. Oh if you play Tracy Chapman, the bass can be full bodied, it’s just there as needed. The MAP-1 has more “color”, and in a nice listenable way.

Does the XP-10 sound like tubes? I don’t know. I haven’t listened to tubes enough to say. The unit is WAY more open than what I expected, and the cymbals and brushes ride out in the open, and not off a surface. They don’t have artificial “zing”

Imaging is solid as a rock with BOTH units. But, the XP-10 has so much more “air” around good source material that it pulls the music away from the speakers, and lets you into the room. The front to back depth opens up noticeably as the micro dynamics describes the surroundings. The MAP-1 can’t match the XP-10 here. OK, the XP-10 is five times the price of the MAP-1 but…it’s what I have as references.

So on scales of 1 (being extremely warm) to ten (being vary hard) the XP-10 is easily around a six or so. It is far from hard, but yet it won’t add color, even if you want it to. No one said everyone looks great without make-up. You pick your presentation and go with it. The XP-10 will divide your music collection into finer groups of perfection. It’s a much clearer piece of glass, what you put on the other side of it is largely what you’ll see. If you have speakers like the Quatro’s or other high definition styles, you will indeed be rewarded. I you like all the edges smoothed away, and to never see adolescent imperfections of raw and rougher sources, the XP-10 may not be for you. I like to see the music as it is, and the XP-10 heads more in that direction.

Associated gear
Ariston RD IIS
Benz Micro Ruby 3 MC cartridge
Moon LP-5.3 head amp
OPPO BDP-83SE Optical player
McCormack DNA-225 amplifer
Vandersteen Quatro Woods

Similar products
McCormack MAP-1
I'll have to keep you posted as I move to Dynaudio C4 II signature speakers. I do like a solid and stiff bass with some punch. Bigger speakers just seem to do this much better. Yes, this is entertainment and I'll color as needed to suit my taste. I like a defined SOLID sound, and the XP-10 seems to be heading that way with C4's. The C4 has a repuation for bass impact, and I did like the sound when I audiationed them! I'll take my "color" right where the C4's place it. The bass change is probably more a magnifying glass than "color" as the bass is still uniform, but uniformly slightly bigger than "flat" (I'm not sure I know what falt is in a real room, however). Like the rest of you, you know your sound when you hear it.

Also, I've read that some pre amps don't like specific amplifier input impedances, and can sound lean as a result. The C4 II's will be run with ODYSSEY KISMET MONO amps with 22K-ohm input impedance, compared to the 100K input impedance on the McCormack DNA-225 running the Quatro's.
The PASS LABS amplifiers are 30/20 K-ohm input impedance, same as the KIEMETS, so the KISMET's should be a better match to what the XP-10 would see with a PASS LABS brand amplifier. I'll just have to wait and see.

I do hope to run the XP-10 into my Quatro's with the KISMETS, however. Maybe I can judge the bass impact some with the Quatro's as the reference and A to B the two amps. The KISMET amp will have to run 24/7 for a week before I really listen too carefully. I'll still have the DNA-225 and can set-up the low pass filters to the Quatro's and go back and fourth a few times.

So there are MANY things that can change the sound. The DNA-225 may sound 100% different with a 20K input-impedance verses 100K with the XP-10, for instance. So would that really be the "amp" sounding different or the pre-amp? I guess it depends on what you want to like the least, and blame.

But this is an expensive hobby, and I just hope to layout what my experiences are so the rest of you can do a better job than I did, and sooner, to reach the sound you're after.

Congratulations on a very detailed review of the XP-10.
I have owned the Pass Aleph P, and the X1.
Now, I own the XP-10. I was quite surprised at how much better it sounds, than the X1.
Regarding your comment on "tube" sound, I'll comment that I also owned the BAT VK31SE. IMO, this preamp does not sound "tubey'. CJ tube gear sounds like tubes, to me.
The BAT VK31SE does not. It is simply quite neutral.
I liked the X1 better than the BAT. It simply had a bigger soundstage, in my system & my room.
How much do I like my XP-10? Enough to buy an XP-20 also...
This could get interesting. I bought a McCormack RLD-1 and sent it directly to SMc Audio for upgrades. It will be fun to see what the two vintage audio gurus can do, Nelson Pass and Steve McCormack.

I LOVE the XP-10 from 200Hz on up, but the last bit of bass impact is softer in my system, for some reason, compared to my older MASP-1. The XP-10 was used, so I'm sure it has "broken-in". It's also been on awhile so it should be stable. It is too polite down low for my ideal taste. So I'm looking for the XP-10 upper frequency sound but with more dynamics in the low bass department. The old MAP-1 has terrific bass impact and extension.

I asked Steve if he might pull it off with a RLD-1 upgrade. SMc seems to think so. If the warmer upper frequency sound is removed in the MAP-1, and replaced with a more full and vibrant yet more solidly etched sound like the XP-10, and keep the MAP-1 bass extension and impact, the platinum RLD-1 could be a winner. But, I'll have to wait till January to find out.

Also, it is probably not fair to say this is an RLD-1 after over $2,000.00 of modifications. And,and,and I'll have my KISMET mono amps and C4 series II speakers broken-in by then. So THAT will also change the comparison, too.

I love things about both pre amps, the MAP-1 (same channel design as the RLD-1 times 5) and the XP-10. Maybe the RLD-1 platinum upgrade will bridge the gap between the two pre-amps? Steve made the RLD-1 and should be able to uncork the design to his true liking and not a price point so much. The RLD-1 build quality is already superb stock so it will last a long time.

Any RLD-1 SMC upgraded commentaries out there?
Wow! that sounds very cool...i have had some success with mods before. With a guy like steve mccormack, that is hard to beat. Good luck and pls post when it comes back in January.
I was debating between a XP-10 and an XP-20.
I really didnt like the two box set up of the XP-20.
But, I was told that due to the XP-20 seperate power supply that it did a little better with the lower frequencies.

So, I purchased the XP-10 and a JL F113 sub.
I've been quite pleased with my decision.
Hey OZZY, Ya' know something? I added two Velodyne DD10+ subs in true stereo with the XP-10 and it's dynamite. Well, it can play the sound of dynamite, that's for sure.

As good as the C4's are, the addition of subs hi-passed in at 80 Hz is amazing. So I can relate to your decision to buy the XP-10 and a sub. I can tell you for the improvement the sub makes, you're sure to be happy.
Hi Rower30,
How do you connect sub(s) to XP-10? I have a sub that is currently driven by a receiver sub preout and I'm thinking of getting a XP-10. My sub has 2 L/R RCA ins and a single balanced in.
The Pass Labs has 2 sets of outputs.
One with RCA's and one set with balanced.

If you are use the Balanced out's for your main system , then just use the Pass Labs Rca outs for your Subwoofer.

But, if you are using the RCA's on your Main system , then the balanced outs can be used with your Subwoofer.
With only one subwoofer you would need to use just one of the balanced outs from the Pass Labs Amp.

I ended up getting another F-113 Subs, with the 2 subs both Sets of the Outputs from the Pass Labs are utilized and the bass is better balnced.
Hi Ozzy,
Thank you for the reply. I just ordered a XP-10, arriving tomorrow.

1) If I use RCA for the sub, do I need both left and right or a Y-splitter will do the job? Do I need "subwoofer RCA" or normal RCA would be okay?

2) I read somewhere that using balanced outs to the amp gives the best performance. I can use either RCA or balanced but the other one would be for the sub. What would be your recommendation?

3) How is XP-10 sub integration and performance? IME with receivers, Anthem performs quite well in that regard than Pioneer or Integra. I'm a little worried with Pass because the outs aren't designed for subs like the receivers.
I have an XP10 in a simple 2 channel configuration w/ no sub. Re question 2: The Pass gear definitely is designed to run with balanced, so use that by all means out to your amp and use the RCA out to the subs. You'll get the highest voltage and cleanest output and more gain that way, with the least amount of noise. I'll let others with "sub experience" address your other questions, and good luck and enjoy your XP10. It is a great preamp. And you can always call Pass direct if you have questions about best way to set it up, they'll be glad to help.
I agree with Swanny, use the balanced outs to your main amp, and the RCA's from your Preamp to the subs.

For one sub don't Y off from the Preamp left and right to a single cable to the sub.

Not sure if your sub has left and right inputs, if so use those connected to the Pass Left and right RCA outs with 2 cables.
If your sub only has one input use just one RCA out from your Preamp. Somehow, though I just didn't like that set up, I always thought leaving one RCA not used from the Preamp as a bad thing.

But, again the best set up is using 2 subs one for each channel, but it costs the most.

The best cable for your sub is usually the one that gives the best bass response. That could be a regular RCA interconnect or a special subwoofer type cable.
Sorry, I know that is not a very specific.
I used ONE output from the XP-10 or RLD-1 platinum to the DD10+ stereo subs. I used the RIGHT channel input on each sub (LFE input) since it is already left and right out of the pre-amp.

From the sub, you can use the "thru" RCA output or 80 Hz / 100 Hz high-pass output RCA's to the amplifiers.

If you have balance input to your amps, you can do the same thing by going from the XP-10 to your amps, and use the XP-10 RCA's to the sub(s) input. This option required that you only use the main speakers full range, however, and digitally EQ the subs into your main speakers response.

You lose the ability to take the load off your main amps, and to reduce IM distortion on your main speakers bass drivers (reduce cone excursions that can effect the midrange and back EMF to your main amps) with the full range option, though. But, listen to it each way and decide the benefits.