Yes and an original member, so searching it only found this of any use, but sadly no component specs:
Hi GM
I just joined the Tannoy group and have been searching diligently and reviewing uploaded files etc.
I read that same thread you quoted more than once.
I found a few different crossover schematics that were uploaded for the Edinburgh. The SRM12x is readily available on Hans’ site.
Not sure what is “authentic” or what the reason for the varying Edinburg schematics are or how trustworthy they are.
I have been reading about methods to bypass the autoformers in these by choosing a specific coil and resistor to use in its place that mimics one of the “tabs” on its selector.
If I were to attempt building a crossover myself it would be my first. I would want it to be as minimalistic as possible in order for me to have a decent chance of success.
On another note, I dropped Mainly Tannoy a note. Gave them a description of what boxes I might be interested in and the driver info.
I kind of got a standard “Yeah we can build you something…it will have these features and the cost will depend on how pretty the parts are.”…no insight given as to what the circuit would mimic or be like at all.
I understand not wanting to give away your “trade secrets” but how is one supposed to make an informed decision based on that?
I’m starting to feel like maybe these posts digress too much drom the original topic and that perhaps a new thread needs to be broken off.
I just joined the Tannoy group and have been searching diligently and reviewing uploaded files etc.
I read that same thread you quoted more than once.
I found a few different crossover schematics that were uploaded for the Edinburgh. The SRM12x is readily available on Hans’ site.
Not sure what is “authentic” or what the reason for the varying Edinburg schematics are or how trustworthy they are.
I have been reading about methods to bypass the autoformers in these by choosing a specific coil and resistor to use in its place that mimics one of the “tabs” on its selector.
If I were to attempt building a crossover myself it would be my first. I would want it to be as minimalistic as possible in order for me to have a decent chance of success.
On another note, I dropped Mainly Tannoy a note. Gave them a description of what boxes I might be interested in and the driver info.
I kind of got a standard “Yeah we can build you something…it will have these features and the cost will depend on how pretty the parts are.”…no insight given as to what the circuit would mimic or be like at all.
I understand not wanting to give away your “trade secrets” but how is one supposed to make an informed decision based on that?
I’m starting to feel like maybe these posts digress too much drom the original topic and that perhaps a new thread needs to be broken off.
Greets!
OK, just 'covering the bases' so to speak and for any others just lurking.
Dunno, didn't open any attachments, links, just at a glance it seemed mostly about replacing the autoformer 'on the cheap' or maybe buy one here if suitable or if you can buy the [delivered] parts cheaper elsewhere...........
Over time I've posted near enough all of them WRT the various types of cab alignments, which nowadays anyone using Hornresp can 'slide' their way to as good [or better in some cases] using its various Loudspeaker, Horn, Wizards/templates; and WRT XO design, have never bothered to learn/use the 'more components, the higher the cost the better' design philosophy to get as much as practical a 'billiard table' flat/whatever response both on and off axis, though if I were to go this route, would use VituixCAD or similar to input a known XO for a particular Tannoy/whatever combo and tweak in room to 'taste'
.
But this assumes one ~ knows how a particular response will perform in room, otherwise better to mock up a 1st order with [cheap] components and begin the tedious 'hands on' listening tests using one or more pots to mimic the autoformer, any other resistors in the circuit to dial in the fixed resistor values, and if there's no caps, inductor values, then use 'textbook' values as a frame of reference.
1st order = 0 deg phase shift, so with a 90 deg phase shift/octave, each driver ideally needs a flat BW between the desired XO point and its [4] octaves away frequency points.
Assuming 500 Hz:
Fl = 500/2^4 = 31.25 Hz
Fh = 500*2^4 = 8000 Hz
From this we see that one needs a cab alignment that's either ideally flat to the driver's Fs or the speaker's in-room response, so in most cases better to use at least a 2nd order on the woofer [or nowadays, 4th order if DSP] and 2nd order on the HF, i.e. what the pioneers concluded circa the late 1920s.
A good compromise then would be the mean of the speaker's ~flat BW = [Fl*Fh]^0.5, so assuming a ~40*15 kHz ~flat BW common back when these coaxes were coupled to either a high output [~matching impedance] amp or one with variable DF tone controls rounds up to 800 Hz, so not surprisingly why it's the most popular of the traditional XO points.
Of course you'll be using a much higher XO point, but wanted to make it a minor teaching example of the potential pitfalls of arbitrary XO point/slope choices.
Then there's baffle step compensation [BSC] if not in the corners and the time delay offset [TD] between the horn, woofer to deal with in the XO [gapping] if Tannoy didn't account for it physically by design [can't remember ATM]..............
Agree, this thread is about Tannoy Onken builds, so pretty far afield ..............
OK, just 'covering the bases' so to speak and for any others just lurking.
Dunno, didn't open any attachments, links, just at a glance it seemed mostly about replacing the autoformer 'on the cheap' or maybe buy one here if suitable or if you can buy the [delivered] parts cheaper elsewhere...........
Over time I've posted near enough all of them WRT the various types of cab alignments, which nowadays anyone using Hornresp can 'slide' their way to as good [or better in some cases] using its various Loudspeaker, Horn, Wizards/templates; and WRT XO design, have never bothered to learn/use the 'more components, the higher the cost the better' design philosophy to get as much as practical a 'billiard table' flat/whatever response both on and off axis, though if I were to go this route, would use VituixCAD or similar to input a known XO for a particular Tannoy/whatever combo and tweak in room to 'taste'
.But this assumes one ~ knows how a particular response will perform in room, otherwise better to mock up a 1st order with [cheap] components and begin the tedious 'hands on' listening tests using one or more pots to mimic the autoformer, any other resistors in the circuit to dial in the fixed resistor values, and if there's no caps, inductor values, then use 'textbook' values as a frame of reference.
1st order = 0 deg phase shift, so with a 90 deg phase shift/octave, each driver ideally needs a flat BW between the desired XO point and its [4] octaves away frequency points.
Assuming 500 Hz:
Fl = 500/2^4 = 31.25 Hz
Fh = 500*2^4 = 8000 Hz
From this we see that one needs a cab alignment that's either ideally flat to the driver's Fs or the speaker's in-room response, so in most cases better to use at least a 2nd order on the woofer [or nowadays, 4th order if DSP] and 2nd order on the HF, i.e. what the pioneers concluded circa the late 1920s.
A good compromise then would be the mean of the speaker's ~flat BW = [Fl*Fh]^0.5, so assuming a ~40*15 kHz ~flat BW common back when these coaxes were coupled to either a high output [~matching impedance] amp or one with variable DF tone controls rounds up to 800 Hz, so not surprisingly why it's the most popular of the traditional XO points.
Of course you'll be using a much higher XO point, but wanted to make it a minor teaching example of the potential pitfalls of arbitrary XO point/slope choices.
Then there's baffle step compensation [BSC] if not in the corners and the time delay offset [TD] between the horn, woofer to deal with in the XO [gapping] if Tannoy didn't account for it physically by design [can't remember ATM]..............
Agree, this thread is about Tannoy Onken builds
, so pretty far afield ..............
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