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Face The Music
15-12-2008, 13:53
Hi All!

I'm fairly new to the forum but I'd like to pose readers a little Christmas teaser...

For the past three years I had been pretty satisfied with my Naim/Neat Motive 2 setup. The sound was detailed and enjoyable, the bass seemed to go pretty low for such small boxes and the system appeared well balanced and musical.

However, I had a niggling doubt that I was missing out on something. A number of related events pushed me to the decision to try changing my speakers.


An article by David Price in Hi-Fi World singing the praises of infinite baffle loudspeakers and criticising the plethora of poor sounding reflex loaded speakers
The polarised opinions that surround the Isobarik speaker. People either seem to absolutely love them or hate them.
My conclusion that whilst turntables, CD players and amps have all advanced both technically and in performance terms over the last thirty years, the humble loudspeaker has progressed the least far. This view was strengthened by reading Martin Colloms excellent book (High Performance Loudspeakers).
The quote (I forget from whom) that as far as loudspeakers are concerned, "a good big-un will always beat a good little-un."


An opportunity arose to purchase a rather tatty looking pair of vintage 1982 DMS Isobariks and I thought what the hell, I'll spend a bit of time restoring the cabinet finish and making some new grilles and I'll still be able to get my money back if I don't get on with them. So I took the plunge and bought a pair of 26 year old speakers...

There is much folklore and many words of wisdom written and spoken about Isobariks in hi-fi forums and pubs alike:

"They are very difficult to drive. You need at least a Naim 250 power amp and going active is really the only way."
"They have a very coloured sound and don't image well."
"They are as ugly as hell and have the lowest WAF of anything under the sun."
"You need a large room to let them breath."
"You need two people to lift them."

From my experience I can now confirm that one of these statements is true and the rest are false. But can you guess which?

Neil McCauley
15-12-2008, 14:25
For what it's worth - and flying in the face of conventional wisdom, in the 1980s (at Subjective Audio) as one of the very few Linn retailers who was not a Naim retailer through choice, I commissioned Bob Stuart of Meridian to build six Meridian active amplification systems for six pairs PMS Isobarics.

This comprised three mono 105 power amps per channel i.e. six in total. These were carefully numbered because there was no crossover in the system. Each pair of 105 mono power amps had their characteristics tailored to meet the needs of whatever pair of drivers were being driven. So, one pair drove the bass, another the mid and another the top.

This was very successful indeed. However both Bob and I concluded that there was only limited appeal in trying to convert the proverbial sows ear’ into a silk purse and we moved on to more musically credible ventures.

One particular instance stands out. I visited a Linn/Naim user in the 1980s who was so appalled by the Isobaric’s mid range colouration that he had disconnected the Linn’s mid range and wired up the system using a pair of Quad ESL 57s for the mid – using all Naim power amps and the NAXO (I think). It was rather good,

Anyway, I had previously got Bob to modify one pair of the 105s to drive these Quads and the other 4 mono amps remained as above.

The customer was overjoyed and the Naim amps were immediately discarded by him. I have to say, notwithstanding the fact that memory can be unreliable, my overall impression of these ghastly looking Linn speakers, with the Quad ESL 57s and the 6 x 105 power amps was very good indeed. Meridian (directly) and Quad (indirectly} were able to bring out the very best out of what was previously and in my opinion a mediocre and over-priced speaker system.

DSJR
20-12-2008, 12:08
Active Isobariks in the early days needed the old bolt up Naim 250's to even begin to sound good. The lack of midrange eq and basic crossover slopes still made for a screaming mid and top if the speakers didn't like one's room. The detail retrieval was awsome though back then and way above most domestic systems (The meridian M1 was hugely funky and fun by comarison, although bass heavy in rooms the 'Briks liked)...

The advent of the Naim CB amp styling caused the sound to harden noticeably and although knowing about the Meridian active 'brik system, we sold a couple of Nytech based ones and although not as powerful, they sounded rather good as I remember.

Passive 'Briks were always a horrid compromise, even in far later years with better cabinets and the high powered mid units and external stand mounted crossover. No two pairs ever sounded quite the same and it was pot luck as to whether you got a tolerable version. My walnut pair from mid 2004 were quite smooth, but a black pair I bought from Jimmy Hughes the following year (the subject of an aborted Isobarik "celebration") sounded truly dire, KEF having altered the B110 causing the shreeky mid to become even worse (the LS3/5A suffered too and it killed the Kan).

Best leave 'Briks back in the eighties these days. get some cheap SBL's instead - they're far better versions of this sound balance IMO.

jandl100
21-12-2008, 20:08
"They are very difficult to drive. You need at least a Naim 250 power amp and going active is really the only way."
"They have a very coloured sound and don't image well."
"They are as ugly as hell and have the lowest WAF of anything under the sun"
"You need a large room to let them breath."
"You need two people to lift them."

From my experience I can now confirm that one of these statements is true and the rest are false. But can you guess which?

OK - I'll play :) ....

from my limited experience of Isobariks I'd go for the statement I've put in bold.

... although I suspect your answer may be the WAF statement below it. ;)

DSJR
21-12-2008, 21:19
Having read again, I'd say that one statement is wrong and ALL the rest true! In my younger days I carried mine upstairs one at a time on my own and the TNT delivery guy could carry a pair into the shop, one on each shoulder, so to say that they need two people to carry them is the incorrect one!

Snoopdog
22-12-2008, 13:15
How well I remember buying that Linn Isobarik PMS/Meridian 105 six pack active system from Howard on 24th April 1981!

The six Meridian 105S monoblocs were serial numbered B3928, B3932, B3937, B3938, B3942 and B3946 and the Isobarik PMS monitors were 11453/11454.

My Subjective Audio invoice for the purchase shows the amplifiers totalling £2400 and the Linn speakers £1661.

More than 27 years later, £4K seems pretty cheap for an active system, that while it might have had a lot of faults 'back in the day' could really rock!

I played my music on that system for mosy of the 80's, selling it in December 1988 for a move back to a passive system (Audio Research SP9/Arragon 4004/TDL Monitors).

I wonder who owns the system now or if it's even still functioning?