Hi!
I've got a pair of old TP1 units - the London type with the short top horn. These came with EX4 drivers which were simply too top heavy and the top horn needs converting to the longer 150Hz type used in the recent "Imperator" design. I have cut a pair of 4mm pieces of MDF to insert and bend into place to test out changing the horn profile and the results are promising.
Having taken out the EX4s and used them to good advantage in some other horns, I'm using a pair of PM2C units with the new style rolled back whizzer and this seems to tame the PM2Cs very well.
The question is phase plugs. The effect is very subtle. I have tried the ordinary bullet, the Lowther new style pepper pot, and a pair of big wooden door handle types.
I assumed the door handles dispersed treble more, and possibly tamed the Lowther units better, but actually makes them possibly more directional. Psychosomatically I believe the pepperpots make them more directional too, with a focussed line of increased treble on axis. But possibly the bullet, or no phase plug, is best of all . . . but the effects are so subtle that it's difficult to make an objective evaluation.
What are other people's experiences? And especially in front horns?
Best wishes
David P
I've got a pair of old TP1 units - the London type with the short top horn. These came with EX4 drivers which were simply too top heavy and the top horn needs converting to the longer 150Hz type used in the recent "Imperator" design. I have cut a pair of 4mm pieces of MDF to insert and bend into place to test out changing the horn profile and the results are promising.
Having taken out the EX4s and used them to good advantage in some other horns, I'm using a pair of PM2C units with the new style rolled back whizzer and this seems to tame the PM2Cs very well.
The question is phase plugs. The effect is very subtle. I have tried the ordinary bullet, the Lowther new style pepper pot, and a pair of big wooden door handle types.
I assumed the door handles dispersed treble more, and possibly tamed the Lowther units better, but actually makes them possibly more directional. Psychosomatically I believe the pepperpots make them more directional too, with a focussed line of increased treble on axis. But possibly the bullet, or no phase plug, is best of all . . . but the effects are so subtle that it's difficult to make an objective evaluation.
What are other people's experiences? And especially in front horns?
Best wishes
David P
Now, this is going to be entirely personal opinion and preference, but....
I have DX2's (EX2's with the back removed) that came with the pepper pots (lemon squeezers) and DX3's that came with bullets. Yes the lemon squeezers are more directional, and if there is anything that the DX's can't stand, it is more directional. The huge treble hump goes away something like 15* off axis and the FR smooths out pretty well. But by 15*, the top end starts to sag significantly.
So... Use the bullets and toe them in until the edge comes off the treble. (Don't have the door knobs, so not opinion.
Bob
I have DX2's (EX2's with the back removed) that came with the pepper pots (lemon squeezers) and DX3's that came with bullets. Yes the lemon squeezers are more directional, and if there is anything that the DX's can't stand, it is more directional. The huge treble hump goes away something like 15* off axis and the FR smooths out pretty well. But by 15*, the top end starts to sag significantly.
So... Use the bullets and toe them in until the edge comes off the treble. (Don't have the door knobs, so not opinion.
Bob
I've listened to the 'door knob' with PM4 in front loaded horn (Oris 150). I felt it's not beaming very much. It has an even better HF dispersion than my 7" mid with bullet phase plug (compared up to around 14kHz or so).
I've read somewhere mentioned that the 'door knob' forms a narrower 'window' for the whizzer cone, thus a 'better loading' to the HF. This was designed to work with front horn in which the midrange would be boosted. But I'm wondering why the HF of Lowther needs any reinforce to match the horn loaded midrange...
I've read somewhere mentioned that the 'door knob' forms a narrower 'window' for the whizzer cone, thus a 'better loading' to the HF. This was designed to work with front horn in which the midrange would be boosted. But I'm wondering why the HF of Lowther needs any reinforce to match the horn loaded midrange...
Hello,
here a measurement by HOBBY HIFI 2002,
with Pepper, bullet, and no plug,
might be no plug is the best,
AER uses no plugs, why not?
Hobby Hifi 01 Jan 2002
here a measurement by HOBBY HIFI 2002,
with Pepper, bullet, and no plug,
might be no plug is the best,
AER uses no plugs, why not?
Hobby Hifi 01 Jan 2002
Hello,
I'm interested in DIYing Lowther's Phase Equalizer.
Where can I find its dimensions or a dimensioned 3D model or a scaled 2D drawing of it?
Or, could an owner measures its dimensions and post them.
Thanks.

I'm interested in DIYing Lowther's Phase Equalizer.
An externally hosted image should be here but it was not working when we last tested it.
Where can I find its dimensions or a dimensioned 3D model or a scaled 2D drawing of it?
Or, could an owner measures its dimensions and post them.
Thanks.

I have tried Lowther EX3, then I stripped the drivers to DX3 and tried them in BLH with original Lowther plastic plugs, no plugs and DIY oak plugs. With my horns and room I prefer the sound (by small margin) of oak plugs and I like the looks.
In my opinion Lowther plastic plugs are not worth copying - the picture may help you to make different DIY plugs.
http://www.diyaudio.com/forums/full-range/199884-stojek-horns-diy-round-blh.html
In my opinion Lowther plastic plugs are not worth copying - the picture may help you to make different DIY plugs.
http://www.diyaudio.com/forums/full-range/199884-stojek-horns-diy-round-blh.html
Attachments
I have spent years with the various Lowther phase plugs, but I keep
coming back to the original bullets.
Of course, I am not horn loading my drivers...
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I am horn-loading the DX4's and for a long time I was playing without any phase-plug giving me a more fluid ESL-like sound....BUT less focus in the middle.
Now I use the standard bullets (Arranged a couple of bronze ones
Phase Plugs
Guess this is the sort of question I should answer.
A vast majority of front horn loaded Lowthers use the wooden "light bulb" phase plug. Those who do not generally use an elongated bullet style. Same as Lowther's bullet phase plug, just longer (add wooden dowel).
Effects are subtle. Usually the light bulb plug gives a slightly more extended high, with slightly better dispersion. But I have not heard them in your cabinet.
Guess this is the sort of question I should answer.
A vast majority of front horn loaded Lowthers use the wooden "light bulb" phase plug. Those who do not generally use an elongated bullet style. Same as Lowther's bullet phase plug, just longer (add wooden dowel).
Effects are subtle. Usually the light bulb plug gives a slightly more extended high, with slightly better dispersion. But I have not heard them in your cabinet.
Me. I have them in stock. And they have full return privledges if you do not like them.
I got from you a couple of DX4 on December of 2005. I putt into the Mauhorn and are sounding the best of all my previous speakers.
Best Regards.
Hi!
I make these cast from an original unit. They varied and later designs varied still more. Some appear more conical but the original ones provide a horn profile between the whizzer and the phase plug.
Plaster stabiliser - phase plug doorknob for Lowther DX4 EX4 PM2 PM3 PM4 PM5 | eBay
Best wishes
David P
I make these cast from an original unit. They varied and later designs varied still more. Some appear more conical but the original ones provide a horn profile between the whizzer and the phase plug.
Plaster stabiliser - phase plug doorknob for Lowther DX4 EX4 PM2 PM3 PM4 PM5 | eBay
Best wishes
David P
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