@MarcusDean , Not sure you meant to post your email address publicly, if you want I can put it back. However members would usually start a private conversation for that to avoid their email account being spammed.
I’m giving this thread a jab…
I just picked up a pair of Tannoy K3149 that we’re supposedly out of SRM12b.
They had new surrounds installed, diaphrams cleaned and recentered along with voice coils.
Supposedly “tested” with freq sweep for rubbing etc.
No T/S parameter were tested…this seems to be a vague area (as with most speaker manufacturers) regarding what I could find as “published” by Tannoy.
The work was done by a speaker repair shop owner.
Kind of hoping for the best…they weren’t too expensive and seemed a better alternative than tearing apart my DMT15ii to experiment with.
Anyway, I didn’t get crossovers either.
I thought about trying them in my open baffles bi-amped with electronic crossovers.
In reading what I could find about the drivers I came across the Edinburgh multiport reference as one of the only “domestic” market applications that Tannoy used these in…that sort of led me here.
Was wondering what someone else might have come up with for these drivers either in an MLTL, Onken or otherwise.
If anyone has any designs they’d be willing to talk about or share please drop me a PM or share here.
Thanks in advance
I just picked up a pair of Tannoy K3149 that we’re supposedly out of SRM12b.
They had new surrounds installed, diaphrams cleaned and recentered along with voice coils.
Supposedly “tested” with freq sweep for rubbing etc.
No T/S parameter were tested…this seems to be a vague area (as with most speaker manufacturers) regarding what I could find as “published” by Tannoy.
The work was done by a speaker repair shop owner.
Kind of hoping for the best…they weren’t too expensive and seemed a better alternative than tearing apart my DMT15ii to experiment with.
Anyway, I didn’t get crossovers either.
I thought about trying them in my open baffles bi-amped with electronic crossovers.
In reading what I could find about the drivers I came across the Edinburgh multiport reference as one of the only “domestic” market applications that Tannoy used these in…that sort of led me here.
Was wondering what someone else might have come up with for these drivers either in an MLTL, Onken or otherwise.
If anyone has any designs they’d be willing to talk about or share please drop me a PM or share here.
Thanks in advance
Only have time to do a bit of research and with new surrounds they ideally need to be [re] broken in before measuring full T/S, so short of doing this, can only recommend using the pioneer's Vb = Vas/1.44, Fb = Fs as the most likely to work well down to Fs in room, so loosen them up a bit and find each driver's Fs and assuming no big gap between them, find the mean Fs' = [Fs1*Fs2]^0.5 = Fs' = Fb and the factory spec Vas = 270 L/1.44 = ~187.5 L, vent area = 550 cm^2 [Sd]/3 = ~183.33 cm^2 = 15.28 cm/6" dia., length TBD.
Going with your formulae would result in something very similar in size to the Edinburgh enclosure.
If I remember correctly (it was a long time ago) a port with that diameter results in a port length that is very short ie within range of panel thickness so basically just a hole.
The Edinburgh itself had what Tannoy called a 'variable distributed port' which was essentially a number of slots cut into the front panel which made it look a little bit like an Onken but there was no port beyond the panel thickness and the area could be adjusted by wooden sliders covering more or less of those slots.
If I remember correctly (it was a long time ago) a port with that diameter results in a port length that is very short ie within range of panel thickness so basically just a hole.
The Edinburgh itself had what Tannoy called a 'variable distributed port' which was essentially a number of slots cut into the front panel which made it look a little bit like an Onken but there was no port beyond the panel thickness and the area could be adjusted by wooden sliders covering more or less of those slots.
Hi CD
Thanks for clarifying that for me. I had seen both the xx48/xx49 models listed together at some point, but wasn’t sure what (if any) difference there might be.
I have been to Hans’ website (an overwhelming amount of info there) more than once and seen the document you linked.
I was in several different Tannoy related threads…in one there was discussion of the validity of certain parameters…I think BL in particular.
I’ll just have to keep digging and reading.
Hi GM
Thanks for chiming in.
You’re already talking way above my pay grade…I’ll have to go back through your info one line at a time more than once to understand what I can.
It makes sense that the drivers will be different with new surrounds and need to be “broken in”.
I read previously about placing them face to face and playing a certain frequency through them for “X” amount of hours or days.
I think if I want to pursue any type of cabinet I will need to find someone with a DATS that could measure them for me or invest in one myself.
Crossovers I don’t even want to take a stab at. I would need some one to recommend me a schematic that would be appropriate for whatever cabinet and speaker measurements I come up with.
I may likely be at the mercy of someone like Mainly Tannoy to build one for me…😒
From this thread:
https://www.diyaudio.com/community/threads/please-help-me-build-my-tannoy-edinburgh.118151/
Edinburgh=200L is pretty close…I think I came across that info previously somewhere else as well.
I’m wondering if all that is really needed is the volume and an adjustable port scheme.
Still scratching my head about the crossover. I found a schematic for the SRM12b somewhere…but don’t know if that is of any use. I haven’t found any Edinburgh crossover info as of yet.
Greets!
Hmm, you're not the first, so guess I need to start putting in BOLD what's important for doing a build, so yours: [Fs] or [Fs'] as required, net volume [Vb] 187.5 L, minimum vent area [Av] ~183.33 cm^2, Vd[dia.] 15.28 cm/6" dia..
Using Hornresp because it's quicker than the math: 187.5 L tuned to 32 Hz returns a negative vent length, so dropping to a 5"/12.7 cm dia. [Vd] = ~126.68 cm^2 [Av] vent = a 17.2 cm/6.77" length [Lv]
Note that these specs are pretty much bogus, though WRT using a 187.5 L net cab, then the above vent will be ~spot on tuned to 32 Hz regardless of the brand/model, frame size, etc. driver, so a guide for using an adjustable one or a starting point for empirically finding whatever tuning you want in room using a too long 5" pipe and shortening [higher tuning] or longer [lower tuning] as required.
Some XO info here.
You really need to get the T&S specs for YOUR drivers, I have just been through all this with my Monitor Gold 12RS drivers (including reguass and reassemble), luckily mine match within 2% and we are building 107 Liter cabinets with ports tuned to 29hz. I have the factory sealed crossovers, but I am leaving them sealed and bagged and I had Mainly tannoy build me a new set with aircore inductors and Jantzen silver caps and a little dial that controls midrange energy. My sincere advice would be to get your drivers tested properly so you have the right information to make the correct choice.
If you haven't got the crossovers the SRM12 schematic will be of very little use for you. That crossover (treble part) is based on an autoformer which is rarer than the proverbial hen's teeth. The bass part should be the same for both though. The Edinburgh crossover will be the same as the SRM12.
Try finding the crossover schematic of the DC4000. Same driver but it does not use the autoformer in the crossover. Works perfectly well but you lose one of the two adjustments you get with the autoformer based crossover ie you get treble volume but not roll off.
Thanks Again GM
I was almost there after CD chimed in…but now I understand things better.
I’m anxious to get my hands on these drivers.
That linked thread is one that I had popped into previously during my searches. I’ll be reading through it completely.
I’ve got to drop ZM an email. He previously sent me some info regarding an MLTL he built for 15” 38xx that I was interested in. I’d still like to try it, but I’m currently enjoying my DMT15ii too much to consider taking them apart. I think he has some ideas he can share about these drivers as well.
I was almost there after CD chimed in…but now I understand things better.
I’m anxious to get my hands on these drivers.
That linked thread is one that I had popped into previously during my searches. I’ll be reading through it completely.
I’ve got to drop ZM an email. He previously sent me some info regarding an MLTL he built for 15” 38xx that I was interested in. I’d still like to try it, but I’m currently enjoying my DMT15ii too much to consider taking them apart. I think he has some ideas he can share about these drivers as well.
Yes I agree
I was considering putting an ad in the swap meet to either find someone who was close by and wanted to make a few bucks measuring them or that wants to sell there tester.
@CD
Thanks, I hadn’t seen those pics yet. I’m spending quite a bit of time exploring info on that site and others.
ZM bounced me back an email very quickly with MJK’s MathCAD sheets modeling a 3149r in an MLTL that he had. Apparently the same box he suggested if I were willing to rebox my DMT15ii drivers.
He explained (similarly to GM) that the the box and its dimensions are the same for any driver tuned to a certain frequency. However, the port specifications and stuffing would vary. It seems a somewhat empirical approach (with patience) is par for the course.
I searched in vain for any information regarding the DC4000 crossover. I found a Groups.io Tannoy group. Is this the same as the Yahoo group? Haven’t successfully found crossover info there yet either.
Thanks, I hadn’t seen those pics yet. I’m spending quite a bit of time exploring info on that site and others.
ZM bounced me back an email very quickly with MJK’s MathCAD sheets modeling a 3149r in an MLTL that he had. Apparently the same box he suggested if I were willing to rebox my DMT15ii drivers.
He explained (similarly to GM) that the the box and its dimensions are the same for any driver tuned to a certain frequency. However, the port specifications and stuffing would vary. It seems a somewhat empirical approach (with patience) is par for the course.
I searched in vain for any information regarding the DC4000 crossover. I found a Groups.io Tannoy group. Is this the same as the Yahoo group? Haven’t successfully found crossover info there yet either.
Yes, that is the group that used to be the Yahoo group. Somebody there might know things.
You could also try asking Lockwood Audio. I had a couple of good chats with Roger Lockwood but have not contacted them since he passed away.
According to Roger back in the 80s removing the autoformer was a popular upgrade by aficionados however today the reverse is true.
Lockwood Audio
You could also try asking Lockwood Audio. I had a couple of good chats with Roger Lockwood but have not contacted them since he passed away.
According to Roger back in the 80s removing the autoformer was a popular upgrade by aficionados however today the reverse is true.
Lockwood Audio