[MNAudioFan]

Hello To All,

Looking for opinions from owners of these two marvelous loudspeakers.  
We're torn between the two and would like to know why we should go to the IB2 instead of the IB1?  I  know that the IB2 has the 75mm PMC Mid-Range that's supposed to absolutely awesome when you listen to it.

We don't have any dealers in the area, so have spoken to a couple awesome dealers and wanted to get some thoughts on the two.

Also like the OB1, but would probably appreciate the 10" nomex driver just a little bit more!

Thanks!

[James Tanner]

Hi There,

The IB1 and IB2 have the same tweeter and woofer in the same size box so there is little to discuss regarding bass or top end.
That leaves the midrange.
The PMC IB2 Mid has some advantages over the Vifa modified IB1 Mid -
1. much more power handling
2. plays louder with much lower distortion
3. wider dispersion
4. greater sense of projection in the room

I find the IB2 has more of the "you are there effect" but it is also has a more transparent  listen into quality. This can be a plus or minus depending on source material.

james

[afblaster]

In the last five years I have owned FB1, FB1+ and OB1 speakers. I have just bought a pair of IB1's, having decided against purchasing the IB2's for the following reasons.  I was very happy with the sound of the mid and top of the OB1's, and I expected that the same mid-range and tweeter  would provide a very similar performance in the bigger speaker.  I had been told that the mid-range of the IB2 is extremely revealing - possibly too revealing for my modest sized room (18ft x 12.5ft).  The final reason was that the IB2 is simply too expensive!
 
I had a home trial of the IB1s for several days which confirmed my thoughts about the mid and top.
But  - the bass was quite simply the best I have ever heard in a (large) domestic-sized loudspeaker, and I have owned quite a few in 40 years.  The bass is tight and very deep, with absolutely no overhang or boom. I believe it is a characteristic of PMC transmission line loudspeakers that they tend not to excite room resonances, unlike bass reflex or ported speakers. This is certainly true with all the PMCs that I have used in my room.  On a good recordings the imaging is so exceptional that the room boundaries simply disappear.
 
I think that the OB1 is almost the perfect loudspeaker.  But for me it has a shortcoming in that I could not turn up the volume on heavy bass material, for example the lowest registers of cathedral organ music, heavy electronic 'dance' music e.g. Chemical Bros, heavy percussion e.g. Kodo Japanese drummers, or the Blue Man Group, without the bass driver audibly complaining.  The IB1's pass these 'stress tests' without blinking!  I use a 4B-SST to power them, by the way.
 
In case you haven't seen the comments on PMC's site, I attach a link to the relevant page http://www.pmcloudspeaker.com/quotes/ib1_quote.html .
Also a couple of reviews from the Bryston site:-  http://www.bryston.ca/pmc_rev/aiib1.html
and http://www.bryston.ca/pmc_rev/amib1.html
 
and a couple of other quotes from reviews I found using Google:-
 
'One of the most popular professional monitors on the planet, the IB-1 takes everything that is special about the OB-1 above and expands upon it. This is a bigger and more dynamic version of the OB-1. While both use the identical midrange and tweeter, it is the special 10" nomex/kevlar woofer which sets the IB-1 apart. This woofer offers unbelievable speed and punch and is the same woofer as used in the Reference Series IB-2. This is the top of the line in the PMC regular series and is a VERY VERY formidable loudspeaker with astonishing sound quality and the best bass response anywhere near the price. People who own this speaker are simply in love with it!'
 
and
 
'The real king is the IB1. This is an unforgettable loudspeaker and is the model Spielberg used for the first time when he mixed the sound track for Private Ryan in 1997! It is a three-way design with the fabulous fabric dome tweeter and mid-range as used in the OB1, but differs greatly by way of its flat 10" piston driver made of Kevlar and carbon fiber. This loudspeaker will produce bass to down unbelievable levels and will teach one what real bass reproduction is. This is a must hear loudspeaker. One customer stated that it kicked to the curb every other loudspeaker he had ever heard! Experience this for yourself.'
 
I feel that I have finally found a pair of loudspeakers that do everything I ask of them, and I can't foresee a situation where I would willingly change or dispose of them. I hope you enjoy yours, whichever model you choose.

[akhc]

I have to admit I never considered the OB1s after a listen between that and the IB1s at the dealers dem room. The bass on the IB1 is several magnitudes better i.e. more accurate and quicker to stop and start though there is still a tiny hint of bloom and box resonance that a live performance (of say an organ) does not have (applies equally to the IB2s). Still I can't think of another speaker that I'd rather have than the IB1s but I must admit to a bias for TL speaker.

Vis a vis the IB2s, well.. if my budget had stretched that bit more I would have gone for them though not anything larger I don't think (bearing in mind the size of my listening room of 20' by 15'). Though James has suggested that the IB2 midrange has a more transparent listen, I have to say that the IB1s are pretty transparent in their own right and such transparency can be off putting especially with poorly recorded source material. Having listened to both extensively I can't say that the IB2s make poor recordings sound any worse than the IB1s do.

What would I do if I were you? Well if the budget is available I'd suggest the IB2s because the midrange is simply that bit more accurate spatially but also because I find that it projects male voices more naturally. To my ears the IB1s reproduce female voices (and by this I mean predominantly operatic voices) better than male ones. Whilst the female voices come off with a very well rounded edge, the male voices have ever so slight an edge compared to the female ones though this is still better than say the N802s which I also auditioned extensively before buying the IB1s.

Bottom line, I am very happy with the IB1s but someday I might just find a pair of IB2s too .

[jethro]

I would like to thank James, akhc and aftblaster for their excellent replies. I've never had a chance to compare my IB1's with any other PMC speaker and I've wondered for a while whether the OB1 was a replacement for the IB1 and what the differences were compared to the IB2. Your replies cleared up a lot of questions. I would also like to concur with akhc that I have found the IB1's spectacular with female voices. I thought it was just a preference for female vocals but perhaps it's the IB-1.

MNAudioFan,

If you choose the IB2 route, I believe the IB2 uses the same mid and tweeter as the MB-2 and the BB5. If I am correct, then you would be getting the best that PMC makes, aside from slightly more bass extension with the bigger models.

I'm not sure if you are going with a surround setup, but I can highly recommend the IB1 center for music (especially) and HT. There are some cuts from Pink Floyd, AC/DC, White Stripes, etc when played on my system (in PLII-Music)  that you could swear that you are being pounded in the chest, yet the voices are clear as day and the bass is tight.

[Thunder]

I upgraded to the IB2's about a year ago. I have my IB1's in storage. One of these days I should get around to selling them Ofcourse if someone was interested in buying my IB1's I could demo them against the IB2's to help you decide

At any rate, James articulated the differences between these speakers very well. Despite the fact that the IB1's are a truly awesome speaker, I find the mid range in the IB2's to be more resolute, bringing me closer to the music, as though the performers are in the room with me. Further, this additional transparancy/ detail does not make the speaker less musical or too harsh IMHO. The IB2's are remarkable.

If they had not come out with the IB2's and James had not convinced me to try them, I'd be very satisfied with my IB1's, they rock.

[declancd7q]

OB1+
------

Revised Kevlar/Nomex Piston bass driver (from AML1)  & revised X'over.....now we are talking stormin speakers.......

Just a suggestion....

[ec]

I upgraded to the IB2's about a year ago. I have my IB1's in storage. One of these days I should get around to selling them

Thunder,

I thought you sold those IB1's last year when you put them up for sale here.  Hmmmm you might have to pull them out of storage shortly <hint hint>  Back on topic, I have never heard the IB2's but I have heard the IB1's and the first thing that struck me was clarity of the midrange even at louder levels.

[dan_lo]

Just wanted to comment that the IB2 are superb speakers. The best I've heard. The midrange is spectacular .
I wanted to buy the OB1, and then I made the mistake of listening to the IB2. I simply couldn't bring myself to buy the OB1 after that.
 IMO the law of diminishing returns does not work here (but that is subjective).

[Riccardo]

Just wanted to comment that the IB2 are superb speakers. The best I've heard. The midrange is spectacular .
I wanted to buy the OB1, and then I made the mistake of listening to the IB2. I simply couldn't bring myself to buy the OB1 after that.
 IMO the law of diminishing returns does not work here (but that is subjective).

The only problem is that as soon as you get used to the IB2 you'll have the MB2s on your wish list  
The scary thought is that after that you might want an active MB2-XBD  

If budget allows go for IB2's, very revealing.