Chris Rogers did 2 versions. Both called Pro9TL. First had B139/B110/T27/Coles, second B139/K040/Peerless/Coles. Second one was commercailly available a the Cambridge R50.
dave
I really would like to get these speakers going and get some sound. How do I get the 4ohm seas tweeter and the 16ohm coles connected
Dave, the area that is inside has a labyrinth so it is a tl I just haven't drawn it, plus the weight and dimensions. The dimensions are exactly the same apart from height as my Pro9's mk1
I will take pictures of the crossover and trace pictures to the wiers and drivers showing which have been connected together by series/parallel ? What ever its been.
Having your circuit board image translated into a schematic would help in identifying where each of the attached coloured wires should go.
That's not easy to do from a distance. You are in the best position to try tracing out the schematic as you actually have the board in your hands. The members here will be good at rectifying any mistakes you make.
The dimensions and construction details of the enclosure are simply a distraction so forget about that aspect of your loudspeakers for now.
You can supply us with more information by listing the values marked on the capacitors (in order from left to right).
Take a Sharpie and draw in where the components on the other side are. That will make it easier to suss out.
dave
dave
In the UK Falcon Acoustics was the producer of many x/o board in the seventies until the mid eighties, when it went belly up, so my pre-paid order of "improved" IMF TLS 80 boards ended up in the Receivers pockets. But I got a nice letter from that Receiver...So this may well be a Falcon board.
That is the time Wilmslow more or less took hold of the diy scene.
That is the time Wilmslow more or less took hold of the diy scene.
Not to make too much of a finer point if it, but where is the source of a Pro9TL MK1 and MK2 distinction?
The B110/T27 design was published in HFNR&R, not making any reference to the PRO9 name, whereas to my best of knowledge the "real" PRO9TL, bearing that title, was published in Practical Hifi.
The B110/T27 design was published in HFNR&R, not making any reference to the PRO9 name, whereas to my best of knowledge the "real" PRO9TL, bearing that title, was published in Practical Hifi.
Dave posted drawings a few years back
https://www.diyaudio.com/community/threads/chris-rogers-pro9-tl-drawing.66848/
There was quite a long article on the build of the mark 2 version including the crossovers I can’t seem to locate just now.
https://www.diyaudio.com/community/threads/chris-rogers-pro9-tl-drawing.66848/
There was quite a long article on the build of the mark 2 version including the crossovers I can’t seem to locate just now.
The top photo in post 20 look very much like the Bert Webb speakers from Audio Amateur mag from 1978.
I remember some version of PRO9-TL with Kef B139, Seas 11FM and Ciare (?) 1" tweeter. The box had a three-part tunnel like the Falcon version. I may still have copies of that project somewhere.
I had a pair like this ages ago, without the 'door' containing the crossover.
Perhaps they are still around, somewhere?
Ironically I always thought it was a bit bass light, but the rest sounded Ok.
Consider studying the Isobarik crossover for a well sorted B139/B110/Tweet, the supertweeter was always a mystery but I'm sure the cats appreciated it.
I have noticed a weird 'thing' about 70s HiFi however, that despite the advances in tech since then, whenever I walk into a HiFi store these days (rarely as there are few that survived the Uniform Business Rates and lack of decent music), modern stuff always sounds 'polite', whereas the 70s stuff to me sounds much more involving.
That's not true for real HiFi, but perhaps more of a 'What's for sale for £1000s in HiFi shops now' viewpoint, dull, enclosed, even super expensive new Quad and Mission stuff. Dull dull dull. 🤷♂️
So I'll be interested in what you think when they are fixed up!
Perhaps they are still around, somewhere?
Ironically I always thought it was a bit bass light, but the rest sounded Ok.
Consider studying the Isobarik crossover for a well sorted B139/B110/Tweet, the supertweeter was always a mystery but I'm sure the cats appreciated it.
I have noticed a weird 'thing' about 70s HiFi however, that despite the advances in tech since then, whenever I walk into a HiFi store these days (rarely as there are few that survived the Uniform Business Rates and lack of decent music), modern stuff always sounds 'polite', whereas the 70s stuff to me sounds much more involving.
That's not true for real HiFi, but perhaps more of a 'What's for sale for £1000s in HiFi shops now' viewpoint, dull, enclosed, even super expensive new Quad and Mission stuff. Dull dull dull. 🤷♂️
So I'll be interested in what you think when they are fixed up!