4 ohm (or 6) Bookshelf speakers. Pass Labs 30.8

Hi everyone!

I am having a hard time finding book shelf speakers that run in 4 ohm (or 6 maybe?).  Before I seriously consider the Pass Labs 30.8, I need to at least know what kind of speakers to listen to, price them out, etc.  I am just now building a system and have no speakers, but I see it looks like the 30.8 is ideal for not that many speakers (from what I can see).  Google didn't help much. I live in an apartment, and the room I have isn't ideal for floor speakers, and is perfect for a lower watt amp, I'd rather pay for quality over power I won't use!.  Bass from floor speakers could also be an issue so I'd rather not even entertain that idea.   If 4 ohm and small speaker don't really go together, I will consider the 150.8 instead.  

Many have said "Any 4 ohm speaker", but being able to find a 4ohm book shelf has left me with not much, so far. 

If this isn't really in the cards (small speakers and 4ohm), feel free to be blunt.  Save me time.  :)

So here is what I have found so far.  Any others?  

1.  Harberth Super HL

Thanks everyone in advance.
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Showing 14 responses by mplstereo

Thanks everyone!  

Wow, this amp was underrated that much?  

Yogiboy - I read in forums from individuals (who may have been uneducated or misinformed) that to get some volume/power get a 4 ohm speaker, that this would bring the output to 60w/ch.  To be honest, researching this amp has been really confusing. I don't know much about ohm's at all.  And now I'm understanding that the amp really makes 100w/ch at 8 ohms fully class A.  SMH, guys like me can't read between the lines with this high tech stuff!

Jackd - Yes, I read that too!  But I just didn't understand it.  I mean, the underrating is so much, that i almost didn't consider it because I was feeling it wouldn't work well with many speakers.   Their power specs are frustratingly misleading and seems weird.  So it stays class A all the way to 100w/ch?  That's plenty for me, but what gives?  Why such the variance?  

So I think the question I need to be asking, just so I am clear, is: are there types of speakers I need to avoid?  (This whole underrated concept and 4 ohm preference talk is making this confusing!  ha)

Also, to be clear, in 4/8 ohm, it stays class A  to 100w/ch?

What about efficiency?  I read that it prefers speakers above 85 for sensitivity?  

It sounds like I should have no issue driving any book shelf speaker, at all, or floor for that matter.  

Any catches, things I might not be seeing?  

Thanks again everyone!

    Found a hometheaterhifi review that compared the 30.8 and the x150.8, and it really secured my interest in the xa30.8 over the x150.8.  Also I did follow up with reviews comparing 30.5 to the 30.8.  This also explained the class A and AB for both and bumps with what your saying.  This has been very helpful.  My listening levels are low.  I enjoy long hours of listening after work, while relaxing, and reading online.  Rocking out for me would be volume loud enough just to the point where I wouldn't hear a person speaking from 5 feet away or so, rarely.  I was able to get enough volume out of my Bose mini when I had that, those little rechargeable ones.  :)  

    Plowed through reviews, did see a lot of identical speakers among listeners, most were panel or floor, and few bookshelf (which partly worried me) but now that I have learned I have more freedom then I thought I did with bookshelf's, I'm not as concerned.    Maybe most folks that have these amps have more room in their home for larger setups so bookshelf's just are not as popular for that reason?  No matter.  

   Thank you for helping clarify this stuff.  Now I feel like this amp is way to good for me!  Kidding.  
Synergy, ok.  I will have to focus on that when eyeing speakers.  Given the cost of the amp, used, it will be a bit after I purchase it before I get speakers, so I hadn't totally thought that far, other than at least validating most book shelf's will work ok.   Tentatively, I wasn't planning on anything over $2k/pair, not that I need to or am aiming to go that high. I will have to find a Pass dealer, probably just buy the speakers there, and I really want/hope I can listen to some speakers with the 30.8.  
Thank you everyone for your help, I will be looking into these speakers!  It's great to hear from everyone that has them and can speak for them and also clear up some confusion I had about the amp.  Seems pretty consistent, regardless what I do, buy good speakers and son't cheap out!  That's ok, that just means I'll have to sell some items and save longer, but hey, for an end all Hi-Fi (as long as it lasts), buy once cry once.  Thanks again everyone.  
@georgehifi   Agreed, that is what I am shooting for.  Just, not a boat load of 4/6 ohm shelf speakers out there, but they are out there, and increasingly enough it seems I have enough options to consider this amp as something for me (where as before I was concerned there just wasn't a selection of 4 ohm speakers in the shelf form).  Do you think very sensitive speaker, say 95 or higher @8ohm, would be just as good or better than a speakers sensitivity at 85 with 4 ohm?  Do you have a preference?  Just curious, seems like both methods might get the same result, just different ways.  Thanks!
@stttt Those look good, thanks!  Added to list!

" I’ve run a 30.5 through an AR pre to 8 ohm 86db sensitivity speakers in a fairly small room. No problem at all with volume to pretty loud levels. I don’t believe it ever got out of class A but have no way of verifying that. Pass will also tell you that there is no sudden change in sound when it goes to A/B. If mine ever changed to A/B I didn’t know it. This 30 watt amp was tested long ago by Stereophile to output about 150 watts I believe, which is slightly higher than the .8 model."

Thats helpful to know, and even surprising!  Great to hear from some one that owns the xa30.  8 ohms and 86.  Well, sounds like I am being a little to careful here.  Just curious, what make/model of speakers?  

@razorbraun Thanks!  That speaker is now on my short list.  How do they sound at lower volumes?  The limited reviews I came across noted that to sound full they had to be "pushed" a little, or turned up.  I'm seeking speakers for low to moderate listing volumes, and if this is true, the 400's may not be right for me.  I want this speaker to be right for me though, and might just try it!  Thanks!
@jaybe I emailed them, and Kent was helpful with providing a lot of information on how to determine what was best for my set up, but did not mention specific speakers, except one that was to expensive ($13k/pr).  I was hoping by now, I would have an idea of what would work well for me, and have a base of dozens of speakers, and go from there.  

Many have mentioned here, as supported in a stereophile review, that the amps lower output is not a big deal, because it goes into A/B after 30/w and will go up to 100/w or more.  And so for that reason, I should be less concerned about ohms/sensitivity.  Well, if that is the case, and I'm running in A/B most the time for my listening, what was the point in getting an amp for it's A class properties?  And I can't really know how loud a certain any speaker will be until it's in my room.  (why the variables are important)

This is certainly one reason I'v been looking at 4 ohm speakers, to take advantage of the power bump from the amp (up to 60w/ch), which opens up a lot more options and leaves me feeling a bit more confident the amp will remain in class A.  I do prefer lower listening volumes up to moderate, but still want to err on the safe side leaving my self plenty of room in A class (plenty being relative, I know this isn't a mono block), using A/B when I'm more in the mood for loud music and won't care so much for the sound as I would in a quiet mood.  (personal preference)

I feel that the xa30.8 is still a  good candidate given my listening room is small and my preference of lower volume listening, but don't want to pigeon hole my self with a high end amp and only lower volumes in class A.  If this isn't the right setting for it, what is?  Another area of struggle for me when learning/reviewing speakers is ohms vs sensitivity. I'v read a lot and am getting much better at understanding, still hazy.  If 4 ohms bumps up the power, to 60w/ch and sensitivity means more volume with less power (sort of), where do they equal?  Meaning, is a speaker with sensitivity of 100 at 8 ohms as loud per watt as a speaker of sensitivity 85 at 4 ohms? 

The mission here isn't for me to quibble to much over the numbers (which I am because I'm not an expert), but rather, find the right threshold, single those speakers out, then I can listen them, with confidence, knowing they will work for my set up, not wasting time on speakers that certainly won't. Keeping the amp in full class A up to and at moderate listening volumes is the goal.  A few examples here that were listed were some 4 and 6 ohm speakers, all with low sensitivity though. (and why can't we have sensitive 4 ohms?)  Then there are 8 ohm speakers with high sensitivity.  They may all work well.  

This is much more important when buying used speakers that I can't listen too.  Some I can audition right here in my home and plan on doing so after I get the amp, but, I still need to make sure that the amp it self isn't so limited with speakers that will allow full class A with moderate listening volumes, that is the tricky part.  It's looking a lot better for me and this amp, but still concerned it's class A properties may be a bit limited (and that might be ok, I don't need every speaker option).  
@ostrey93 Those speakers look like good ones, too.  Do you think they might not be up to par with the amp?  I only say this because of the sweeping cost difference between the amp and speaker, and it may not matter that much.  Also, how do the speakers sound at lower volumes?  I know some need to be pushed just a bit to sound good, according to some, and am seeking a speaker that does well at lower volumes  Not any easy task, but some speakers do it better than others.  Bass is not that critical, bass presence is, but full sound at lower volumes is what I am really seeking.  Thanks!   
@stereo5   Yea, I hear ya there!  I am doing my best to be realistic with the right speaker, trust me.  I may go up to $2500 new/used.  That's pretty significant, but so is the amp.  Due to cost, the purchasing will be over a time frame, and reflect goods sold from my home.  :)  Most importantly I just want speakers that, at a minimum, will remain in the amps Class A range to my common listening levels and not switch over to A/B all the time, eliminating the heart of the amp, sort to speak.  I have read, however, this speaker, the s400, doesn't perform well at lower volumes and needs moderate volume to sound full.  Could still try it, but if the two reviewers that stated that are right, it's not for me.  Will seek more insight from owners.  Thanks for your input!
@jsautter   Thanks for the input!  Just to make sure we are on teh same page, my goal is to keep the amp running in class A for my listening needs.  at 8 ohms, it produces 30w/ch.  at 4 ohms it produces 60w/ch.  So, there is more headroom fro Class A, making it a bit more practical for when/if I want to go a bit louder, though I do prefer lower volumes.  60w/ch isn't much though in a world of massive mono blocks!  Should be fine for me though.  

When you say "perform better in 8 ohms", what do you mean?  

Once I can validate a speaker will very likely produce the volumes I am seeking, I'll add it to the list of speakers to listen too.  An 8 ohm speaker at a sensitivity of 86 will likely not be ideal, for example.  I want to give the amp a chance, and have to be selective in the speaker to do so.  

" The Aerial 5t is a 4 ohm speaker. BTW, why do you feel that you need a 4 ohm speaker? The impedance changes with most speakers!"

Ok, well, I don't know anything about impedance changing.  Not that I needed another variable in the mix, but if it's there, it's there!  One thing I did not clarify earlier on because I was still learning, was that I want to stay with in the amps Class  A rating, and at 8 ohms, that is only 30w/ch.  By going with a 4 ohm speaker (as in, only 4 ohm), the amp is now making (advertised) 60w/ch, fully class A. 

So I guess in short, my answer is volume and headroom.  How much of that I'll need depends on the speaker and likely the source, too. Though my listening levels will tend to be low, sometimes moderate, I can appreciate knowing that I have some flexibility there.  60w/ch still isn't a lot, most amps today make 100/ch. 

One thing thats hard to pin, is what is the minimum wattage any speaker needs to sound full or at it's potential.  That varies with speakers, and I don't know how to validate what power they need minimum.  Maybe most book shelfs only need 10 watts to sound good?  Others, more?  And thats where sensitivity comes into play.  Most book shelf speakers, or stand mounts, seem to be rated 85-86.  Not helpful with low output amps.  95 would be a different story, etc.  But I seem to be finding more and more 4 ohm speakers,not so much highly sensitive ones.  I do know Klipsch makes some, though.  So, that said, I'm also open to highly sensitive speakers, I just don't know at what sensitivity level they are on par with twice the volume, which would only be needed as a reference point so I could calculate other sensitivity figures, too.  

WOW.  So as far 4 ohm/ 8 ohm, im not getting "louder" (for this specific set up), presuming the sensitivity is the same.   Or at least I am not doubling my volume like I thought I would be. That explains some of the responses that I didn't understand.But, increasing sensitivity is the key to getting a bit more volume out of a speaker, not dropping to 4 ohm.  Now this is making a lot more sense, I was having a hard time understanding why such an amp would only play nice in class A with so few book shelf speakers. That was extremely helpful.  

I used the calculator, 30w at a sensitivity of 85 is plenty loud for me, as loud as I'd ever really want to go it seems, in my given room.

Looks like I have much less to focus on that I thought, and will restart my speaker search to include 8 ohm.  I knew some used 8 ohm but just figured it was because thats what they had, and said it worked just fine. I presumed they were in A/B mode then.   

Point noted and advice taken.