I have just gone on the Lowther site:
https://www.lowtherloudspeakers.com/
which is interesting in a couple of ways. They have gone a bit upmarket. The factory made cabinets look much better made, with prices to match. £7000 - £18000 (+drivers!) that I looked at. The response curves look fairly realistic, (like the HF drop off at 9-10k) and confirm, that, without front horn loading, the PM6a 8ohm silver voice coil gives the flattest response.
However the most interesting thing I saw was that with the factory made speakers like the TP2 they recommend adding the “Lowther Super Tweerer”. A definite break with history.
https://www.lowtherloudspeakers.com/
which is interesting in a couple of ways. They have gone a bit upmarket. The factory made cabinets look much better made, with prices to match. £7000 - £18000 (+drivers!) that I looked at. The response curves look fairly realistic, (like the HF drop off at 9-10k) and confirm, that, without front horn loading, the PM6a 8ohm silver voice coil gives the flattest response.
However the most interesting thing I saw was that with the factory made speakers like the TP2 they recommend adding the “Lowther Super Tweerer”. A definite break with history.
Wow. Thanks for the info. I haven’t gone on the lowther loudspeaker website in a while now. Will have to check it out? Jeff
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I've got one of their drivers in a box somewhere in my basement, one of the smaller units but I can't remember which. Always been fascinated by the lore around these drivers. The PM6a 8Ohm Silver is indeed the only 'normal' driver they offer and this is the one I'd use if building an Open Baffle for example (Nelson leads the way on that). That isn't what I have though, so I'll have to concoct a horn for it. Even then I've often felt that these drivers will do their best when used as Mids, or as Full Range with Woofer & Tweeter support but DIYAudio doesn't yet have an acronym for that.
I would say that the tweeter is welcome addition. All the full ranges I've heard have had compromised highs due to size (beaming transducer) or design, including lowther style ones. A proper integrated tweeter could perhaps solve that to a degree. Regarding the HF drop off at 9-10k, I think that is being quite positive maybe on axis, similair lowthers looks to have the drop 1-2 octaves lower (http://www.troelsgravesen.dk/Lowther.htm).
Although I really don't get why one would add a tweeter as it throws away the good things a solo fr has like:
In my opinion if you're (considering) adding tweeters and woofers to a fr one might aswell get a normal mid(woofer) which are way better designed for that frequency band, but than you're back to where your (probably) started...
Although I really don't get why one would add a tweeter as it throws away the good things a solo fr has like:
- All sound coming from one source in space.
- No complicated crossover and it's related problems
- The ease of use and setup
In my opinion if you're (considering) adding tweeters and woofers to a fr one might aswell get a normal mid(woofer) which are way better designed for that frequency band, but than you're back to where your (probably) started...
I suspect Lowther may plan to re-release their legendary/mythical Hegeman-Lowther Reproducer, which, based on sims, should produce some pretty excellent sound from a PM4. They have Malcolm Williamson -- cabinet maker in the UK -- building a pair for them.
http://www.malcolm-williamson.co.uk/Work+In+Progress
http://www.malcolm-williamson.co.uk/Work+In+Progress
Interaction with a client also shows that the PM6 works in a reflex enclosure. 3 versions now.
dave
Jeff Drouin’s woodwork. He has built a bunch of miniOnken. https://www.diyaudio.com/community/...ken-gallery-pictures-only.214897/post-6269919
dave
Not quite. Not That's Hegeman's "Standard" Speaker (licensed to EICO as the HFS-2).
I'm talking about this one:
http://www.lowthervoigtmuseum.org.uk/lowtherHegeman.html
Front and back loaded horn, yes. But The Lowther faces forward in the center of the plaster horn. I have a copy of the original bass horn drawings.
Front and back loaded upward firing Lowther? Are plans somewhere?
dave
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This is an important point you remind me of - integration of tweeter and mid is a huge compromise and why we prefer full range drivers. Perhaps the trick is the choice of XO. A typical multi-way would have a fairly low XO to the tweeter because most dedicated mid-range drivers are not designed to go high, plus the issue with matching dispersion. I've read that people adding super tweeters with higher XO's do not perceive issues in listening to their speakers that might be predicted based on comb filtering, dispersion mismatch, time misalignment etc.
If I add a tweeter to my Lowther driver, it will be similar to what Dave has posted and the XO may be somewhere above 5kHz
p.s. I think it's most appropriate that the thread starter is 'midrange' 😎
Are the three versions for different variations of the PM6 (silver vs copper/ aluminum voice coil, AlNiCo vs ferrite magnet) or are there three versions for the PM6a?
Long time ago I was using DX type of Lowthers, on open baffle. I never had an impression it needed tweeter or supertweeter. It needed to eq the lowther shout out, after that it was quite enjoyable.
Off course it needed help below 150Hz, being on open baffle, but I never meant to play with back loaded horns anyway.
So it was essentially a BassZilla speaker, off course many years earlier than Dick Olsher posted it on his site.
Off course it needed help below 150Hz, being on open baffle, but I never meant to play with back loaded horns anyway.
So it was essentially a BassZilla speaker, off course many years earlier than Dick Olsher posted it on his site.
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The 3 versions (in order of development) are for PM6A 16Ω silver coil, PM6C 8Ω copper coil, PM6A 8Ω copper coil. The first 2 are the same size, the later larger. I have not yet looked at the others.
dave
dave
Is the email address on your website correct? David@(your URL). The file is huge, so I will send you a DropBox link.