Upgrade from Pass Labs XA30.8 to X250.8. Worth it?


I am getting ready to make some upgrades to the system. I currently running a DAC into a BAT51SE, then a Pass Labs XA30.8, then finally into Decware DM947 speakers (don't worry if you've never heard of them; not the last word in speakers, but have been doing a solid job for about 5 years now.)

I am contemplating moving up the Pass Labs amplifier line, and the X250.8 looks attractive. I would like to hear more bass authority and definition, but I don't really want to sacrifice the mids and highs of the 30.8. 

I would love to hear some of your impressions of the X250.8, especially if you are able to make some direct comparisons to the XA30.8. I've spoken with both Mark at Reno Hifi, and Kent English of Pass Labs; both are wonderful and informative people. What I am interested in now is the opinions and experiences of end users of either of these amps. 

Thanks! 
willrich47

Showing 19 responses by willrich47

Greg, thanks for the comparison. Exactly on point. I just wonder how many people make the switch after hearing them side by side?

George, I did some research a while back on the DM947’s. I tracked down what I believe is the actual driver for the speaker. It’s called the “Silver Flute.” 

The drivers themselves appear to be relatively inexpensive (hence not highly advertised), but they do sound a lot better than the parts price suggests. They do have the benefits of a crossoverless wide-bander.

You can find them here: 

https://www.madisoundspeakerstore.com/approx-8-woofers/silver-flute-w20rc38-04-ohm-8-wool-cone/#prod...

@twoleftears I was once intrigued about that particular amplifier. I asked Mark at Reno Hifi about it, and he indicated that the 30.8 does just about everything better than the XA25. Though admittedly, I haven't compared the two. I did own the 30.5 before the 30.8, and could compare those two if you'd like! 

@jafant I was fortunate to find a copy of my B.A.T. on Audiogon. It had been recently recapped and was in great condition. I came from a tube amplifier. The B.A.T. has a slightly warm and dark sound to it, which I really like. I am always striving for simplicity in my system, and I have taken it out a few times to decide whether I could "live without" it. As soon as I remove it from the audio chain, I immediately miss it. I am definitely a proponent of having tubes SOMEWHERE in your audio chain. Love that sound!

@hk_fan Thanks for the response. This is why I posted here. To get a wide variety of opinions on the topic, even if they are conflicting. I am a bit confused though because Mark seems to think that the X250.8 is a solid upgrade from the XA30.8. Kent seems to like the X250.8 very much too (claiming to keep that one at home a majority of the time) but admits that it isn't as warm as the 30.8. I'm hoping to find some of those "happy customers" Mark was referring to; or even some unhappy ones. 

@snopro the sentiment is not lost on me. I am still trying to wrap my mind around why bigger AB amps often times have better bass, even though the output may be the same as a class A amp. Even more within the Pass line. Moreover, why does 1 Class A watt from the X250.8 sound different from 1 watt from the XA30.8. No idea, but trying to learn! 

Thanks all for the responses so far!
@browndt that amp is also intriguing. There’s one listed on Audiogon right now. Do you have personal experience with those two amps X350.8 and X250.8? 

@hk_fan You’re not wrong. Indeed, that is how my current setup works. I have an SVS SB-16 picking up the lowest frequencies. 

Part of getting a sub integrated is making it not call too much attention to itself; just picking up the frequencies that are lacking in the speaker itself. Most of the bass I am hearing in my system comes from the XA30.8. 

I remember one of the very first “hi-fi” systems I heard 5 or so years ago had a very tactile, visceral feel to it. No matter the subwoofer I use, the 30.8 is not going to produce that visceral aspect of the music. 

I would agree, the mids and highs are second to few. My hope is that further up the Pass line somewhere is an amp that has more of that power, but with the finesse in the mids and highs that the 30.8 has.

I used to own the XA30.5; it was a great amplifier. It replaced my Decware Torii Mk IV, which I was sure, was going to be my ‘terminal amp.’ When I got the XA30.5, I thought I was taking a huge chance on it. I didn’t expect it to perform well against my valve amp and figured there was a 50/50 chance I would be disappointed and sell it. I was surprised to find that the Pass Labs XA30.5 eclipsed my Torii in almost every way. 


The XA30.8 sounded different in a couple of ways. For starters, it sounded great cold! Maybe better than the XA30.5 warmed up. 


There are plenty of other differences between the two amps. For example, the 30.8 is darker, much smoother, clearer, images better, and voices may be pulled back just a hair. It's got more mid-bass, which I like a lot (reminds me of my tube amp). Its bass is overall much punchier, tighter, clearer. The 30.8 sounds much more powerful overall.


On top, the main difference between the XA30.5 and XA30.8 is that the XA30.5 has a 'sweetness' on the very highest frequencies. I don't hear it with the XA30.8. I liked the sweetness on the XA30.5, but there are bound to be a couple of gives and takes. 


I can see why you like the 30.5!!




@bobheinatz honestly, that is really the heart of the decision I am making right now. I’ve got a pretty good offer on the X250.8 that I am interested in taking. But for the same out of pocket price, I could also get a pair of Tekton Double Impact speakers, which everyone is raving about. (Incidentally, Tekton’s HQ is not far from where I live and they’re willing to let me come in for a listen.)

My goal is to add a bit of slam to the already great sound my system produces. The Double Impacts are nearly 4 times as sensitive as what I’ve got, but does that necessarily translate to more of the “slam”? I don’t know. 

I know the X250.8 will probably give me more of that and probably a bit more detail and space too. But like you intimated, my mid-fi speakers are probably the limiting factor in my system. I’m just trying to determine what gives more of what I’m looking for: the speakers or the amp?
Wbud,

thanks for the advice. I thought Mark at RenoHifi’s unsolicited reference to that review was interesting as well:

“Terry London's review says that the X-250.8 and XA-60.8 sound "the same."   I don't agree that they sound the same, but they are certainly very close in sound.  The X-250.8 has more power and is more economical, so for almost everyone, the X-250.8 would be the way to go.  The XA-60.8's are at least $3000 more than the X-250.8.”
@tjassoc thanks man! The comparison is helpful. There are so many opinions out there, some informed, some not, it’s difficult to know for sure without hearing. At this stage I think it best to aggregate the opinions I am getting to make that informed threshold decision: whether to order the amp for the in-home trial.

Although not the exact amps I am asking about, your comparison does carry a lot of weight. 

I’ve heard great things about the 200.5’s too. I assume they bested your 30.5? ;-)
I live not far from the Tekton Design home office. I went in today to have a listen to the Double Impact speakers. At first listen, these were incredibly detailed speakers that had most of the improvements I was hoping for in an amplifier upgrade. 

I think my next purchase will be from Tekton. I’ll revisit the amplifier question a bit later. 
@tjassoc I’ve read your last post a few times. I’d love to get my hands on a set of 200.5’s. Every review I’ve read makes me think those are THE amps to own. Perhaps even over the 200.8’s. Thanks for the insights.
@tjassoc I agree with both of you on the power conditioner. It’s definitely on my wish list.

I’m in the middle of a new home build right now. One thing I wanted in the home was dedicated 20A circuits for the stereo. I even increased the amperage of the breaker box just to make sure I’ve got plenty for the future. 
@david_ten thanks for the report on the exact system I want to upgrade to! 

When I visited Tekton Design, they had their DI’s set up with a tube amp. The logo said “Raven” on the front, and it appeared to be using a pair of EL-34’s for each channel. Maybe 25 watts or so. I didn’t get a close look.

Through the DI’s, that tube amp seemed to have some punch and grunt. I know how those kinds of amps typically sound. They usually sound a bit weak on the low end. I know the XA30.8 is going to make the Double Impacts sing!
Just for clarity, the SVS SB-16 subwoofer is still the single best sub I've heard. I simply think the impedance drop is having a negative impact on the sound of the overall system. If I could use it without changing the load on the preamp so much, I think I would have some stunning results. 

I thought I would follow up to give some closure to anyone reading this down the line. I always like to hear how people’s decisions turned out. Hopefully you do too. 

 

I purchased the Tekton Double Impacts, largely due to the advice I got from members here. While I am not ruling out an amplifier upgrade at some point in the future, I think the Double Impacts have had a more significant impact on my system, than an amp upgrade would have. 

 

The Tekton Double Impacts: 

 

The DI’s need some time to break-in. When I actually got my pair, I was surprised to hear they sounded “OK.” And by “OK,” I mean thoroughly OK, middle of the road, mediocre, and most of all: disappointing. But, it didn’t take long for the midrange to start opening up. The mid and upper range only took about 3-4 days to open up and sound wonderful. The bass, was a little different. 

 

I’ve been using an SVS SB16 subwoofer for a little over a year. When I started using the Tekton’s, it seemed apparent to me that the sound was improved with the SVS. A little over 30 days after getting my Tektons set-up, the bass seemed to change. All of a sudden, there was too much bass. I turned my sub down. A couple of days later, it seemed like too much again. This time I turned the subwoofer off. I eventually achieved the best integration with the SVS by crossing over at around 35-40 Hz. My RTA app on my phone says I had a relatively flat response down to 20 Hz. 

 

I remembered an email conversation I had with Victor Khomenko a while back. The VK-51se has two sets of balanced outputs on the back. I had asked VK if they could both be used at the same time. He said they could, but I had to be aware of the combined impedance of all the amplifiers attached to the VK-51se. 

 

My Pass Labs XA30.8 is relatively easy for my preamp to drive. The balanced input impedance is 100K Ohm. The SVS SB-16 on the other hand, is not as friendly; its balanced input impedance is 22K Ohm. I believe the combined impedance is found through the calculation (100 X 22)/(100 + 22) = 18K Ohm (I would appreciate if someone with some actual EE knowhow would fact-check me here).

 

As an experiment, I removed my SVS SB16 subwoofer from the system entirely. In my system, the DI’s start rolling off at about 40 Hz, so I lost some bass extension from the removal of the SVS. But what I gained was more drive and authority from the DI’s, and more color and clarity through the entire range. 

 

I don’t believe that I noticed this with my old speakers because they simply lacked the clarity of the DI’s, and did not have the same bass extension. With the old-speakers, the SVS simply improved the overall quality of the system. With the DI’s, there is a clear trade-off. Bass extension for overall sound quality (especially bass quality).

 

I have had my SVS completely unhooked from the system for about 2 weeks now. After about 1 week, I added it back to the system and found I disliked how simply hooking it up to the preamp affected the system. I quickly removed it from the system again. This has been an unanticipated side effect of adding the DI’s to the system, and has all but de-railed my plans for a second SVS-SB16 subwoofer. 

 

If anyone has some clever tricks for getting around this problem, I am all ears! 


@bobheinatz I think you were right ;-)


@bdp24 I was thinking along the same lines. I was hoping to do it without replacing the SVS. I've been searching for a high-level to RCA input converter, but haven't found a suitable solution yet. 

But you might be right. Maybe REL is where it's at. I am a little surprised that SVS doesn't offer this type of input solution, especially on their top-of-the-line unit. I have to think that more preamps would have this issue than just mine. Could be wrong though. 
Haha, well, I just confirmed what I heard in this review of the BAT 51se: 

"The balanced output impedance was twice that specified, at 410 ohms over most of the audioband. This is low, though it did rise to a high 4.7k ohms at 20Hz, due to the size of the output coupling capacitors. (There is only so much room within the chassis for these high-performance but physically large components.) This will not be an issue with components having high input impedances, such as BAT's own power amplifiers, but it does mean prematurely rolled-off low frequencies with low load impedances (fig.1), such as those offered by some solid-state amplifiers."

Read more at https://www.stereophile.com/content/balanced-audio-technology-vk-51se-line-preamplifier-measurements

Now the question is, how do I fix it without replacing a preamp?
@ebolyn

Even though this thread is a little old, your observations are still incredibly relevant. When I first started this thread, the question came down to new speakers, or a new amp. I made the decision to get new speakers, which was the right decision at the time. The Double Impacts have had a remarkable impact on my system. 

But it here I am again, looking at the upgrade to the X250.8! In a way, your timing couldn’t be better!