PMC IB1S, not exactly flat are they?

[SafeandSound]

Stereophile: PMC IB-1S loudspeaker

I know it's all in the listening but just doing a bit of research before hand.

Roll off earlier than I thought as well (at least by this graph)

It does beckon whether price rather than performance has more to do with what is deemed a mastering speaker.

I will remain completely open minded till I have heard them, they are definitely in the running.

[nosebleedaudio]

This what I got when I measured them in a studio..Very solid to 30Hz..
A kick will truly hit you in the gut...

[HomeProducer]

Originally Posted by nosebleedaudio

This what I got when I measured them in a studio..Very solid to 30Hz..
A kick will truly hit you in the gut...

with this hole at 150 Hz I could never work. It could cause distortion of small laptop speakers when the mix is muddy at 150 Hz.

[Greg Reierson]

Originally Posted by SafeandSound

Stereophile: PMC IB-1S loudspeaker

I know it's all in the listening but just doing a bit of research before hand.

Dude, you're in the UK! Book an hour at Metropolis. Go to the PMC plant. Get your ears on them and let us know what you hear.


GR

[Greg Reierson]

Originally Posted by HomeProducer

with this hole at 150 Hz I could never work. It could cause distortion of small laptop speakers when the mix is muddy at 150 Hz.

Have you measured your own in-room response?


GR

[HomeProducer]

Originally Posted by Greg Reierson

Have you measured your own in-room response?


GR

yes, and my room has also already a hole at 150 hz without such speakers. They would only exagerate the problem. But I am not the focus here anyway. :)

[nosebleedaudio]

Originally Posted by Greg Reierson

Have you measured your own in-room response?


GR

Right...
Have not seen many speakers that are TRULY flat...can not think of any...
Just for comparison here's a graph of Genelec S30 close and at normal position in a nice studio...
And yes the Normal position is NOT good..but proves a point..

[Silvertone]

Originally Posted by HomeProducer

with this hole at 150 Hz I could never work. It could cause distortion of small laptop speakers when the mix is muddy at 150 Hz.

Agreed, years ago when they first came out I had them in for evaluation (along with the Bryston amps) and could never get past what was missing in the low end. Loved the way the bass extended way down but compared to all the other speakers in the room at that time they were "missing" something in that 100 to 150Hz region.

Loved the size, the concept, the build quality but could not get past the low end... even when I played my Music Man bass through them it altered the low end of that beast... not an easy feat by any means!

[Llitsor]

Surely there is more trustworthy information out there than an 11 year old publication you found on some hifi website?
For one thing, im pretty certain PMC have tweaked the design since then (more specifically, tweaked bass drivers, if I remember correctly. Call/email them to confirm, they are quite helpful folk). Secondly hifi publications are not exactly renowned for knowing how best to use audio testing gear. And even if they do now, they surely didn't 11 years ago. They are a pretentious lot at the best of times..

Still, if other PMC's are anything to go by, I expect you'll need a pretty big room to get the best out of them.

[macc]

It's the screw deficiency innit

[HomeProducer]

Originally Posted by nosebleedaudio

Right...
Have not seen many speakers that are TRULY flat...can not think of any...
Just for comparison here's a graph of Genelec S30 close and at normal position in a nice studio...
And yes the Normal position is NOT good..but proves a point..

insane! That nice studio is much worse than my treated livingroom. :)

[Llitsor]

Originally Posted by macc

It's the screw deficiency innit

Damn you! It did cross my mind you know. But clearly im not as daring as you

[SafeandSound]

Well you may continually jest but the very same review suggested a vibration
from the crossover PCB.

So Macc, you have hit the nail (or screw, snigger) on the head.

I plan to listen.

Actually I have a response plot for the Wilmslow K100 and it is virtually
ruler flat with a not dissimilar roll off and zero evidence of any reflex port hump
or drop outs at 100Hz-140Hz.

Thanks for the alternate graph, it gives scientific hope, still a hole in the bottom.

All in the listening but you know, interesting nonetheless.

[nosebleedaudio]

Originally Posted by HomeProducer

insane! That nice studio is much worse than my treated livingroom. :)

Was not picking on that studio, just making a point how bad some rooms can be and the engineer NOT know it...
"Nice studio" indicated it was NOT some 8 by 8 bedroom studio..if you know what I mean...But a well designed room NOT completely acoustically finished...not in my book anyway...

[macc]

Was just having a giggle man. That said, I don't see how a vibration of the sort I am imagining would cause such a wide dip in the freq response, one would assume it would be fairly narrow band/resonant, no?

Either way, the proof of the pudding is in the listening. I'm off to eat my speakers.

[tresperros]

Originally Posted by HomeProducer

with this hole at 150 Hz I could never work. It could cause distortion of small laptop speakers when the mix is muddy at 150 Hz.

sorry mate, but you saying 'bollox';)
those peaks and dips are within 5-6 dB,
which means that studio has almost perfect, flat response

[SafeandSound]

I don't think the 100Hz-150Hz dip is anything to do with the crossover board
vibration this is a separate issue the mag took to task.

If the first graph is in an anechoic chamber, there are flatter speakers for sure.

The in room response graph was very good. (which is the one that matters most)
Though it still displays a plot in keeping with the speaker itself.

[SafeandSound]

JMK I see you have BM6 there too, are they completely different tonally
to the IB1S?

[nosebleedaudio]

Originally Posted by SafeandSound

JMK I see you have BM6 there too, are they completely different tonally
to the IB1S?

For sure..nice nearfields..

[HomeProducer]

Originally Posted by tresperros

sorry mate, but you saying 'bollox';)
those peaks and dips are within 5-6 dB,
which means that studio has almost perfect, flat response

good to teach me foreigner some new expressions. ;)

I guess that is a free field response.
Then it depends, wether you measure with third octave smoothing or not.

And I have the strong feeling that the frequency response straight out of the speaker has more influence on tonality to human ear than room acoustics (since reflections appear from different directions which might be better "resolved" or learned by the ear). Just a hypothesis though.

[PatrikT]

Originally Posted by SafeandSound

If the first graph is in an anechoic chamber, there are flatter speakers for sure.

Maybe they aimed at the world outside of the anechoic chambers...


Best Regards
Patrik

[SafeandSound]

It appears your response is to appear sarcastic and smart, forgive me
if I misinterpreted it.

Designing a monitor with a skewed response based on an unknown room is
not only foolish but incredibly unlikely.

I doubt it was meant to be funny as I know Swedish humour.

Ok your biog explains :

Audio man doing oldskool analogue smart-ass mastering

[Riccardo]

Just chiming in to confirm that there is no vibration originating from the crossover boards. Once you mange to open the rear panel and disconnect the mentioned board you will realise how firmly they are mounted. Mind you it takes a while.
Unmounting the drivers is also a daunting task as in addition to the much criticised bolts the drivers are sealed (as in glued to the MDF).

[jayfrigo]

Honestly, those measurements really aren't that bad. Considering all the elements, and the measurement methods, they compare favorably to many other studio speakers. You'd be surprised what many popular speaker response graphs look like, and also, how some manufacturers make theirs look better with fudging the octave resolution (smoothing) or scale.

[SafeandSound]

All fair points and I am thankful of them.

In all likelyhood they are probably going to be the right speakers for me.

I have seen 2 high end speakers recently quoting useable reponses to 25Hz and when you see the graphs they look like they roll of rather quick, I found this a little surprising.

[PatrikT]

Originally Posted by SafeandSound

I doubt it was meant to be funny as I know Swedish humour.

It was not and I'm happy Mr. Frigo kind of says the same thing.

If I wanted to be funny I'd have a hotel in Torquay.

Good luck with them speakers.


Regards
Patrik

[dcollins]

Originally Posted by PatrikT

If I wanted to be funny I'd have a hotel in Torquay.

"I'm so sorry, he's from Barcelona."


DC

[SafeandSound]

Hey it's all good Patrik I was being a bit of a d*ck really, no need for it.

My girlfriend is Swedish so I have met a lot of Swedes and I think they may not understand English humour sometimes (and I am not sure I get Swedish either)

My friend lives in Norway now and he says they really don't get it and literally stare at him with a serious face.

[uncajesse]

With a bit of speaker/room compensation even with a little simple EQ work, it becomes a lot less about frequency response, but how transparent a speaker really is.

And "some hifi website" had some surprisingly decent clues about how that might lay out with this speaker, if you compare it to other knowns with the same data.