SpeakerTalk

[proffski]

Same principle as that used by KEF with the activated carbon granules.
I have always wondered about the active longevity of the carbon as it gradually absorbs other contaminants in the air.
Same with this new product... any chemists out there?

http://www.elektor.com/news/miracle-material-doubles-speaker-volume-for.2091163.lynkx?utm_source=UK&utm_medium=email&utm_campaign=news&cat=audio/video/foto
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[audiolabtower]

It must wear out? same as cooker hoods without venting, the carbon foam becomes less useful with age? Maybe with less contamination inside a cab it works for the lifetime of the speaker?... but surely not for some of our classics, 30 years old and still going strong...?

[ColinR]

[proffski]

Sadly that is the sort of answer I was expecting but hoping not to get Colin.

This could be an interesting long term study for somebody, measuiring the performance of a bass driver in an enclousre over eight years in an "average" domestic environment.
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[Thierry]

Product seems to be oriented to cellular phones rather than relatively large bass cabinets used in home loudspeakers : http://www.knowles.com/search/nbass/h_nbass.jsp

[proffski]

I remember the 1st Philips MF loudspeakers from the early 1970s?
The models I listened to were smaller and the tweeter was mounted in the classic position. I heard another pair much later in Delmenhorst, Germany when visiting friends. May have been RH 544s???

Some nice pictures thank you, fascinating!
https://plus.google.com/photos/109296933751482509949/albums/5728370414172947121?banner=pwa&gpsrc=pwrd1
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[Thierry]

The model you listened to was probably the RH532, a 2 ways small box. First issue had a foam surround woofer. Few years later (1975 ?) it was replaced with model RH541, rubber surround woofer and black plastic cabinet. I have this model along with the bigger (3 ways) RH544.
Actually I have picked up some of them for experiments on possible electronics improvements and testing better modern HF drivers than the original one, allowing a lower crossover frequency.

Of course the smaller 541 sounds different from the 544, it has less power in the low frequencies and the 3 ways speaker is able to play much louder as it has 2 amplifiers built in : a 40W amp for the woofer and a 20W for the mid and HF drivers, whereas the 541 has a 20W amp powering the two drivers. But the 2 ways 541 has more consistency in the midrange and better imaging than the 3 ways RH544.
Both models are very, very good sounding speakers in quite small enclosures. Bass is powerful, very tight and controlled. Many people will find them ugly - indeed they look strange - but to me they are wolves in sheep clothing.

link towards pictures showing the innards of the smaller model : https://picasaweb.google.com/109296933751482509949/PhilipsRH541#

Here's my small stack of 2 ways RH541s




The two Philips MF speakers standing beside my beloved 105/2s.

[proffski]

Blimey, you maske my mink Hi-Fi museum look empty and sad.
I had no choice but to sell previous loudspeakers or lend permanently to family due to space restrictions.

I got a nice warm glow from your pictures, thank you!
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[Thierry]

[proffski]

I've had some adventures with the IMF Super Compacts, never been a fan of Bose though...

I recognise some others but a few strangers amongst the collection.
Have you ever heard a loudspeaker with MF working when it goes wrong?
Not for very long...
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[Thierry]

[proffski]

Hmm, the Bose might have gone loud, but not as an average domestic consumer product. All those small units and all that equalisation, not too elegant.
I would vote the AR LST as just ‘one’ of the milestones in the history of acoustic transducers worthy of a mention amongst many others.

Going back to MF, there was a magazine which featured a DIY project, I cannot remember which sadly. For subwoofers as with Velodyne the concept is indeed rather appealing!
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[clubsport911]

I love that collection ! If ever you needed proof that there is diversity in design, this was it. I always think it incredible that the laws of physics apply to all designers, they (mostly) All have the objective of making excellent sounding transducers, but the outcome....is so varied

Of all your collection, it's the Phillips MFB's that I'd like to hear the most !

Good work

[Thierry]

[clubsport911]

My memory on the MFB's is fading somewhat, and if I recall, I first heard them in the early 80's. Am I correct ? They take me to a time when "revolutionary" speakers like the Wharfedale E70 were released (whatever happened to them ) and I felt that there was certainly more experimentation going on.

Cheers