PMC IB1S speakers

Hi guys,

I've got a pair of IB1S speakers. I'm pretty happy with them though they take a bit of getting used to I did find that siting them fairly wide made a great difference. A couple of questions which hopefully someone can answer for me. I do find them a 'little' too detailed with music. Not intrusive actually but I wondered if the film filters would cure that. Also, the IB1S centre is far too big and i was considering the CB6 (when I can afford it). Has anyone tried this combination as I can't find a CB6 to demo? Last but not least, I'm presently running these with a MF A308 cr. I'm thinking of pairing up with Bryston naturally. Will the 4BSST or a pair of 7BSSTs be best? Lot of questions from me sorry but if anyone can help with any of them it would be appreciated.
Cheers,

Bob

 

What is a 'film filter'?

The big PMCs like multiple amps and lots of power, so yes an amp change will do a lot of good.

 

A 4bsst will be fine. The bryston amps all sound the same. I use a PMC MB2-XBD-Active. PMC likes triamping with bryston. The best solution is to get a 4b-sst and then a four channel bryston to go with it (2 3b-sst in one box). Triamping makes a huge difference.

It cant be "too" detailed - is what you really mean to say that it is a bit edgy and accentuates the detail and treble too much? What is the rest of your system?

 

That was quick guys

As far as I can tell a film filter reduces DB at higher frequencies - but I'm not too sure as there isn't a great deal of info about them other than that they exist! I could probably just do the same with manual Audessy with my 3806

Yes, 'edgy' is a better description. Most of my music is via Foobar through my PC. It's fed to an off ramp turbo then into a big ben then (wait for it) into the coax input of my 3806. I use the 3806 for my surround and centre channel and pre out into the A308 for the IB1S mains.
Cheers,

Bob

 

3806? turbo? big ben?

What you are hearing is the likely compression due to the mp3 format of the pc music file plus the limit of whatever dac and pre you are using. Changing your power amp may reveal more of the problem. I would move to uncompressed or lossless audio files plus a decent dac and pre. Worry about the power amp later - it isnt holding things up. Film filters will just be bailing out the basement while there are holes in the roof.

 

The big ben is pretty flawed in stock form, has an odd effect on the bass as well. It can be rectifed
Uprate the psu/regulation to the off ramp turbo and stick in a decent clock and it will start to come together

 

By film filter do you mean a capacitor acting as a low-pass?

If you are already using lossless audio format on the PC then the problem is probably both the quality of the DAC and pre section of the Denon 3806. Borrow a decent pre and DAC (maybe a benchmark DAC1 or a DAX Decade) and see what happens. While the amp is under-powered at 150watts, it probably isn't causing the harsh sound.

 

All files are lossless wav files so there's no compression. I'm playing wav files @ 24/96. The off ramp is just a USB to S/PDIF converter but a good one. The apogee big ben is a master clock. I was using Tact 2.2x as a DAC and being honest I've tried SB3 and others - the sound is equally good through the 3806 so rather than have loads of units in my rack I got rid of a few of them.

I've been using Dynaudio Facette mains for a few years and while the bass was a bit weak compared to the IB1S (hence my Velo DD15) their top end was/is more refined. Having said that, I've just built my system round the Facettes so there's bound to be a difference. Most people who listen to my system are gobsmacked, it's me that is looking for that little bit more

 

Don't forget for the IB1S's I'm using an MF A308 which is rated at 250 w per channel at 8 ohm. I know it's not the best but like evreything else this is an evolution based on finances.

 

The facette's do have a very good tweeter so I'm not surprised. When you have the RCS2.2 did you use it as a DAC or a DAC and pre-amp? If the 3806 really sounds as good as the 2.2 as a DAC and pre-amp then I expect the problem may actually be elsewhere, as although the 2.2 is not the ultimate in sound quality, it was very good when I tried it with my active PMCs.

Have you considered the room? Do you have anything at the first reflection points?

.. I thought the 308 was 250 at 4Ohm?

 

I gotta spend more money huh

The big ben is stock, and the off ramp has just had the output modified to a coax socket so I can plug in a better quality coax cable.

I'm gonna have to sit back and take stock of what you guys are saying before I spend any more big bucks. I have tried so many expensive players and DACs etc but often the hype was more than the result so I have sold em off, consolidated and want to try and stick to the basics.

 

Hi, yes i used the 2.2x as a DAC and pre-amp. It did sound like I was complaining but in fact I now think the term 'edgy' was more accurate. I can listen to music and enjoy it but some tracks now are a bit too sharp. For example I love Christina Aguilera whose voice can be a bit piercing.

I've got smallish bass traps in all the tri corners, and broadband absorbers on front and back walls. Also a couple of ceiling clouds. I had a pretty good curve without using room correction and I used the tact to help me position the absorbers. Just a dip at about 90 hz which is a black hole anyway so generally the room is reasonable.

Maybe I just need to get used to the IB1 speakers

 

What sort of broadband absorbers? Anything on the side walls?

Sounds like you have the room reasonably delt with and if the Denon is no worse than the TacT then I'm not sure what the issue is. It should all be 'pretty good'!

As you say, maybe you need to get used to the speakers. The Dynaudio's you posted in the ads section look to me like they use one of their top tweeters (the D28, right?) so it is not surprising the tweeter of the IB1 is a little bit lacking to be honest...