Few questions for Peter

[Ianm2]

Hi Peter, hope its ok to ask.

1/ previous designs you did?

2/ How long commercially from conception to a finished product? If you have time, you can elaborate. ie decision making process, how is it done?

2/ What equipment you use yourself?

3/ Favourite commercial equipment with an emphasis on amplifiers and speakers?

kind regards, Ian

[Paul Barker]

don't be so nosy.

[petercom]

Originally Posted by Ianm2

Hi Peter, hope its ok to ask.

1/ previous designs you did?

2/ How long commercially from conception to a finished product? If you have time, you can elaborate. ie decision making process, how is it done?

2/ What equipment you use yourself?

3/ Favourite commercial equipment with an emphasis on amplifiers and speakers?

kind regards, Ian

Answers:

1/ Everything at Heybrook up to and including the Quartets but not thereafter (I sold out of the business). Everything at Mission from Jan 1999 up to the point it was sold to the Chinese.
1a?/ From idea to production takes about 9 months. A lot of that time is experimentation, trying out drive units, refining drive units and so forth. Then comes a period of mechanical design - often overlooked in my view in many speaker designs. Then technical appraisal and theoretical crossover development. Next to last subjective crossover development and component fine tuning. Finally production engineering and appraisal. It works better if it's 12 months, but that rarely happens in the commercial world because of poor planning.

2/ It's always changing. Currently a lucky find Pioneer PL-L1000 (too new for cartridge to yet be decided upon) and a rescued Radford STA25 (preamp under development) driving the WD25A (under development). You could say I get bored easily.

3/ Items I've really enjoyed living with are Tim de Paravicini's EAR509 power amps, original Quad ELS and, ummmm, everything else seems to have been ephemeral (though I did have a John Jeffries Reference Lumley system for review which stayed for too short a time). I've left out my own speaker designs obviously.

[Shane]

At Heybrook, you always used bought-in drive units whereas if I'm not mistaken, at Mission they were designed in-house. Were you responsible for the whole lot? And do you design a driver for a paticular speaker, or vice versa?

[petercom]

We never had the budget or the purchasing power at Heybrook to do much more than slight mods to drive units which meant that the speaker was built round the drive unit(s). At Mission I could fit a drive unit design to its intended role which gave greater flexibility to the overall speaker design. I worked closely with a drive unit consultant to achieve the results we needed.
I've just been working with SEAS on the WD25A bass unit and it has been equally rewarding designing that driver to suit the aperiodic enclosure. I take the view now that if a driver doesn't do what is needed then we'll modify it until it does.

[david counter]

as a matter of interest, do you start with the enclosure and then find a driver to fit or do you come across a driver and then think I like that I'll build an enclosure for it

[prince of darkness]

Having designed speakers for my own system, I should think the two ideally go together. An approximate desired box volume and bass response will dictate the Thiele-Small parameters required to select the bass drive units. The Bass drive units will then determine the exact volume required. Treble and mid range (if required) will be dictated by the bass drivers selected and personal tastes.
Must admit my speakers were not designed this way. I obtained a pair of audax twin cone drivers from maplins (discontinued line, so cheap) and designed the enclosure for the desired bass response. The result was huge floor standers. Treble rolled off a bit early, but this was cured by adding motorola piezo tweeters (suitably attenuated). I am very happy with the sound. They go loud with little power (triode connected rogers cadet).

[petercom]

Originally Posted by david counter

as a matter of interest, do you start with the enclosure and then find a driver to fit or do you come across a driver and then think I like that I'll build an enclosure for it

As it is rare to come across a really good driver, when you do find one it is very tempting to build a speaker round it. This is what is likely to happen with World Designs. With Mission, however, the enclosure came first because of marketing issues. As far as I know all mainstream commercial designs now start out that way. We then had to build a driver from scratch to suit the enclosure.

[Brian]

Peter

Assuming you might be able to get hold of the items, might there be any plans to look at previous WAD speaker designs ( cabinets plans and crossover design ) with a view to producing suggested mods?

Not that there is anything wrong with my KLS3 MK2 Gold speakers, but I would be very interested in utilising the Audax HD3P treble unit in a design that uses a 10" or 12" bass driver, for example.

Thanks

Brian