Sussex Hornman
Member
It's been a while since logging into the forum and upon doing so have found some messages unanswered for a few years. Apologies.
One such message asked me for advice and referred to the Lowther Shout. Thus this post.
I've been looking at interesting speakers in the past years including Manger Zerobox 103, Lowther TP1 London, Lowther TP1A, Lowther Audiovector, Acousta, Voigt horn and the large full size Worden Panasona together with some front horns from John Richardson of Prophecy Audio, adopted and enhanced in designs by Mike Wallis with a bass horn to die for.
Many people have asked me to repair Lowther drive units and in doing so I've discovered a lot about the myths and the facts of the Lowther units sometimes having the opportunity to carry out experiments with Lowther cones in AER magnets and AER cones in Lowther magnets.
For many Lowther applications the phase plug is crucial and I'm not a fan of the modern pepper pot as it's directional. The bullets are normally excellent but for front horns, the light-bulb shape is crucial, both in dispersion of sound and in applying proper balance to the high frequencies, acting as an impedance transformer lower down the treble range than the bullets.
When one applies the lightbulb shaped phase plug, there's no need for the roll-back surround design of the whizzer cone. That roll-back muddies the high frequency, creating bouncing and interference, and makes the Lowther sound ordinary. It's best flipped forward so as to give open clean treble balanced by the proper phase plug.
Ferrite vs AlNiCo vs Neodynium. There's a big secret in all of this - the difference in sound wasn't the magnet!
In the PM6C there wasn't a shout that I ever noticed but with the PM2C in a front horn, the aggressive treble of the stronger magnet exaggerated a particular frequency of cymbals, which once heard caused madness ever after. I guess that's why the PM2C isn't on the production list nowadays.
The A series and neodymium series do not suffer from that at all and can be used with the straight cone with impunity. No shout. With them the shout's a myth.
Those speakers of mine take up rather a lot of space. Which will I keep? Um.
But interviewing all of them has given an insight into their strengths and weaknesses and which drivers are best in which units.
TP1 Londons - DX2
TP1A and TP1B - PM5 or DX4
Audiovector - DX4 or PM4
Acousta - PM6C PM6A or PM7A or Audio Nirvana Neodymium
Corner or Dual Position Acousta - PM6 or DX2 facing forward or PM2C or DX4 bouncing off the wall. In particular these can give an extraordinary stereo image.
In addition to the Lowther units I rate highly Audio Nirvana Neodymium and also the David Louis Audio neodymium 8 inch units from Hong Kong together with the renowned Philips 9710 although the treble from that can be beamed centrally and possibly it needs a phase plug.
What I really appreciate about these other units is their reliability - no foam to rot and no fragility of the voice coil . . .
Very many apologies to all those who have sent messages to me unanswered.
Best wishes
Hornman
One such message asked me for advice and referred to the Lowther Shout. Thus this post.
I've been looking at interesting speakers in the past years including Manger Zerobox 103, Lowther TP1 London, Lowther TP1A, Lowther Audiovector, Acousta, Voigt horn and the large full size Worden Panasona together with some front horns from John Richardson of Prophecy Audio, adopted and enhanced in designs by Mike Wallis with a bass horn to die for.
Many people have asked me to repair Lowther drive units and in doing so I've discovered a lot about the myths and the facts of the Lowther units sometimes having the opportunity to carry out experiments with Lowther cones in AER magnets and AER cones in Lowther magnets.
For many Lowther applications the phase plug is crucial and I'm not a fan of the modern pepper pot as it's directional. The bullets are normally excellent but for front horns, the light-bulb shape is crucial, both in dispersion of sound and in applying proper balance to the high frequencies, acting as an impedance transformer lower down the treble range than the bullets.
When one applies the lightbulb shaped phase plug, there's no need for the roll-back surround design of the whizzer cone. That roll-back muddies the high frequency, creating bouncing and interference, and makes the Lowther sound ordinary. It's best flipped forward so as to give open clean treble balanced by the proper phase plug.
Ferrite vs AlNiCo vs Neodynium. There's a big secret in all of this - the difference in sound wasn't the magnet!
In the PM6C there wasn't a shout that I ever noticed but with the PM2C in a front horn, the aggressive treble of the stronger magnet exaggerated a particular frequency of cymbals, which once heard caused madness ever after. I guess that's why the PM2C isn't on the production list nowadays.
The A series and neodymium series do not suffer from that at all and can be used with the straight cone with impunity. No shout. With them the shout's a myth.
Those speakers of mine take up rather a lot of space. Which will I keep? Um.
But interviewing all of them has given an insight into their strengths and weaknesses and which drivers are best in which units.
TP1 Londons - DX2
TP1A and TP1B - PM5 or DX4
Audiovector - DX4 or PM4
Acousta - PM6C PM6A or PM7A or Audio Nirvana Neodymium
Corner or Dual Position Acousta - PM6 or DX2 facing forward or PM2C or DX4 bouncing off the wall. In particular these can give an extraordinary stereo image.
In addition to the Lowther units I rate highly Audio Nirvana Neodymium and also the David Louis Audio neodymium 8 inch units from Hong Kong together with the renowned Philips 9710 although the treble from that can be beamed centrally and possibly it needs a phase plug.
What I really appreciate about these other units is their reliability - no foam to rot and no fragility of the voice coil . . .
Very many apologies to all those who have sent messages to me unanswered.
Best wishes
Hornman