Thoughts On The PMC OB1?

OB1 is deserving of all the accolades and may be one of the best designed speakers under $5,000. Incredibly flat phase response (flatter than most tube amplifiers) in the midrange make these speaker honest and transparent, my favorite amps now that Warner Imaging is gone would be the YBA Passions or for something more affordable the Acoustic Reality amplifiers would be awesome too.

Proac and Wilsons are not competitive so don't waste your time unless you like equipment more than you like music. Use a Behringer 96/24 crossover EQ ($400) on an ATC Concept 4 subwoofer (room EQ and 48db slope with the OB1's and you not only have a system that can best the Sophia's you have a system that can begin to take on the Maxx's.

Some people advertise loudspeakers, some people engineer loudspeakers. Don't pay for advertising. ;)

Thanks Cinematic. Are you suggesting the use of a subwoofer with the OB1? I figured with the transmission line enclosure and rated response down into the 20hz region one would not be necessary in my 15 X 26 X 9 room. I would prefer a full range floorstander that can hold its own without a sub. Also, none of the electronics you mention are familiar to me. How much experience do you have with the OB1? What would you say are the primary needs for these speakers with regard to electronics? Can they be driven with a moderately powerful amp? Do they sound best with tubes or solid state gear? How would you describe the tonal balance--are these typical BBC style speakers with a warm, rich midrange, warmish balance, midbass bump, and rolled off highs? As a Harbeth owner I'm not necessarily opposed to much of this description. Just really curious about these since they seem to offer quite a lot for the money.

Hi Dodgealum,

Thanks for sharing your thoughts with me!

Audio Ideas Guide magazine on the internet has a good review of the OB1 with measurements which will pretty much answer most of your questions. I agree with Cinematic that PMC are a very competent design. When you audition check to see if the bass is to your liking, it could be a bit lean per review and friend.

Good Luck!

"Are you suggesting the use of a subwoofer with the OB1",

The OB1's have very good bass, but often extension is confused with output, and a transmission line is more about quality extension than absolute output. So adding a sub would simply add control and greater output for the last octave of sound. OB1's do not "need" a subwoofer but they will benefit from a subwoofer as almost any speaker would.

The Sophia has slightly bloated bass (WP7 too) to make it sound like it has deep bass robbing the bass of the unique timbre's of each instrument (to a degree, they are not Cerwin Vega's if you know what i mean)) . Do not be fooled by this. And let me say that it might take an OB1 experience to understand this statement fully.

Room construction can also dictate what kind of bass you will have.

"How much experience do you have with the OB1?"

Not a great deal, but enough to know that it is uniquely the real deal, an accurate loudspeaker. You better like your music because its not going to editorialize or boom or tizz or diffuse anything. It can handle modern solid state amplification so buy a good deal of power, because they will play extremely loud and you won't know it because the distortion is very low. Buying room treatments could be argued as essential with a speaker like this (ATC too.) because they will play 10dB louder than other speakers before you think they are the same volume as another speaker system. That extra energy needs somewhere to go.

Understand that accurate sometimes means forward (recordings fault) and won't give you a huge soundstage (if its not on the recording) but what it does mean is that instruments will sound very real and many of your marginal recordings will become very listenable.

"Can they be driven with a moderately powerful amp"

In your room, if you listen to light jazz and chamber music, you might get away with 100 watts, otherwise 200, high current, no tubes, minimum. This extra power is just to keep things clean on musical peaks, not too shatter your hearing with constant output.

As a Harbeth owner I think you will like these speakers, Harbeth quietly makes very accurate loudspeakers and the OB1 I think (my opinion) takes a step towards neutrality from the Harbeth sound, it very well may be a tweener sound between the ATC's and the Harbeth's.

So it would be worth a listen if you can get one. I like the speaker a great deal and it is not well known so don't look to the gallery for a great deal of back up. If you buy a pair you will be on your own till others get to hear what the speaker is capable of through you. Then they'll know why you bought them. :)

Thanks Cinematic. I agree entirely with your differentiation between bass depth and output. The Proac D25, for example, goes down to 20hz but the 6.5 inch woofer simply cannot move a lot of air. You get to "hear" the deepest notes but not "feel" them. This is why if I go with Proac I may have to hold out for the D38, which has two woofers. I haven't been able to scare up an audition yet to see if they are the ticket. I did very much like other aspects of the D25, however, and am also a fan of the Sophia. Since you do not seem to care for either of these I'm not sure we are looking for the same thing from a loudspeaker. I'm not into detail retreivers that are tonally lean. I like a bit of warmth because I think that is the way live music sounds and because it makes up for shortcomings in many of the recordings that I own. Also, domestic constraints make room treatments out of the question.

I'm curious--do you have any additional thoughts on the Proac's or ideas about the Fried Studio 7 or the Vandersteen Quatro?