To Dave. Don't know which model but the guy I bought them from built them sometime about late 70s early 80s. He did an exceptional job. When I first connected them to the valve amp I was amazed with the SQ!! Seriously sounds I've never heard before and I've listened to lots of hifi new and vintage. .
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You may of misunderstood regarding the full range woofers, not all have the potential for really good sound just some that are under the radar e.g. vintage Phillips full range, goodmans axiom and audiom full range, some celestion to mention a few. I've read in the correct cabs there up in the same league with tannoy dual concentric. Time will tell. In 2024 after saving money and accumulating the speakers building the cabs we will know. .
Chris Rogers pro9 tl I believe. Huge, 1120mm H...350mm W...450mmD..
The pioneer are more like 250mm woofer. .130mm mid...110mm horn at the opening..710mm hight of the cab by 550mm width and 400mm depth in corner style speaker. Closest match I found are the cs31 speaker but for the corner. It has a volume knob at the rear for the high frequency. Thats all I know. .
It's not a matter of the cabinet ( and ...wood and derivates should be avoided) but the [physics call it intermodulation] inability to fully reproduce the full frequency range, i.e. vibrating contemporary say at 40 Hz and 13kHz
Those Kef speakers testify that ( the double tweeter nowadays can be one unit...)
Those Kef speakers testify that ( the double tweeter nowadays can be one unit...)
Ok I understand. So there is room for improvement regarding the pro9's by upgradeing of drivers and crossover. I've never been inside them. What do you suggest? Same must apply to the sx410? Have a professional make sure all the parameters are within original specifications. ..I see..thank you
Those beauties ....Perspex! Really bare and naked.
Open baffle (but the full tilted bass EQ needed is not suited for the woofer) with lateral wings...but needs a subwoofer. To be clear: any combination needs a subwoofer, some say...but this is easy.
So no perspex cube or baffle ( the necessary acoustic damping material would not be transparent nor cute to see)
At this point we're left with 3 speakers and a divider.network...some wires and the necessity to make them create a coherent wavefront here and there...
Open baffle (but the full tilted bass EQ needed is not suited for the woofer) with lateral wings...but needs a subwoofer. To be clear: any combination needs a subwoofer, some say...but this is easy.
So no perspex cube or baffle ( the necessary acoustic damping material would not be transparent nor cute to see)
At this point we're left with 3 speakers and a divider.network...some wires and the necessity to make them create a coherent wavefront here and there...
A new enclosure for the B139 would be first. Then i would replace everything else with a good 3 or 4” full range as a midTweeter.
dave
Basically a full re-design. A new transmission line speaker. Im glad we're not discarding the B139. The kef 104 had the B139 as an ABR and to my ears that speaker had the ability even at miniscule volumes to go low...very low. I've always thought what it would be like to have that combination. Think if we put 2 B139's inside a cab like how it's done for car subs...2 chambers @ diffrent volumes(space) with B139's faced together would not need high power to drive and be able t produce frequency as low as it is in real life, effortlessly dynamic speed and accurate. ...yes why not. .and maybe open baffle/horn type for say a full range point sorce 10/12in speaker. Crossover if needed be simple...the simplicity of all, like piont to point wiring no faffing about. ..I think something like that would be beautiful.
https://www.t-linespeakers.org/projects/vProjects.html
3 variations of modern B139 TLs. Bonus if you have 4 x B139.
dave
3 variations of modern B139 TLs. Bonus if you have 4 x B139.
dave