Hi,
I lately got a pair of 15" gold but without the original crossover. The autoformers which were used in the crossovers are not easy to reach. I think the autoformers can be substituted with a fixed coil inductor. I therefore would like to ask if any member has done one before with this same situation. Or any recommendations/ comments are welcome.
Regards
Albert
I lately got a pair of 15" gold but without the original crossover. The autoformers which were used in the crossovers are not easy to reach. I think the autoformers can be substituted with a fixed coil inductor. I therefore would like to ask if any member has done one before with this same situation. Or any recommendations/ comments are welcome.
Regards
Albert
Hmm, inductors roll the top end of drivers off while autoformers pretty much just attenuate the output of a given driver depending on the tap used.
The 'old Gold 15's' had two controls for manipulation of high frequencies. One was for HF energy (shelved EQ) and the other was for HF roll off.
They used a combination of both Multi-tapped inductor, and resistors to achieve this. From memory, the XO frequency was exactly 1KHz.
If I was in your situation > After confirming that 1KHz is correct, I would pursue building a lovely fixed (non adjustable) XO to suet your ears.
Remember, the original adjustments were provided to 'set & forget', tailoring for a listening environment and the listeners ears.
I wish I had your current situation & project 🙂
They used a combination of both Multi-tapped inductor, and resistors to achieve this. From memory, the XO frequency was exactly 1KHz.
If I was in your situation > After confirming that 1KHz is correct, I would pursue building a lovely fixed (non adjustable) XO to suet your ears.
Remember, the original adjustments were provided to 'set & forget', tailoring for a listening environment and the listeners ears.
I wish I had your current situation & project 🙂
The autoformers were indeed used for attenuation. You can also do that with a variable L-pad if you want that flexibility. But i would do as Mister Audio describes, make a new crossover for it without it, and tune it right for your taste from start (based on measurements). Or try to find the original ones, even when it's hard to find them.
Thanks guys. I'd work with the program to find the right value on my place so to make up a fixed value crossover. I have checked with all information on the web but they're mostly doing modifications for them but not building new ones without the autoformers.
I’m not sure exactly what you want. An exact duplicate of an original Tannoy crossover…albeit set to a specific adjustment?
There are options without autoformers. Some Tannoy guys will say it’s blasphemy…not opening that can of worms.
https://mainlytannoy.com/collections/tannoy-speaker-crossovers
I have no affiliation…only ever ordered some ferrofluid from them.
They don’t appear to be using autoformers. How accurate they are to the original design, well 🤷♂️
Another source for Tannoy enthusiasts is Lockwood…
http://www.lockwoodaudio.co.uk/
I have two pair of Tannoy…some 3833gg from System 15 DMTii and some 12 “ 3149 pepperpots from LGMs.
These guys are usually pretty helpful with technical info including original crossover schematics if you join and ask nice…
https://groups.io/g/Tannoy
This is probably the most expansive resource online…
https://www.hilberink.nl/speaker.htm
There are some guys on here that are Tannoy fans if you poke around.
So, sometime in January I bought these classic 30 year old Tannoy CPA12’s after MZM identified the hidden treasures within: Dual Concentric 12-inch 3134’s. To top it all off, MZM has a ML box for these fitting my living room perfectly. And the price was unbeatable @ 500 dollars including an extra tweeter.
But, surprises kept coming. These pics show the drivers upon arrival at my house. Notice the baskets have been painted, and this had been spilled onto the surrounds and in some places also onto the cones.
One of the drivers have had a party with a lit candle. So, these are...
There are options without autoformers. Some Tannoy guys will say it’s blasphemy…not opening that can of worms.
https://mainlytannoy.com/collections/tannoy-speaker-crossovers
I have no affiliation…only ever ordered some ferrofluid from them.
They don’t appear to be using autoformers. How accurate they are to the original design, well 🤷♂️
Another source for Tannoy enthusiasts is Lockwood…
http://www.lockwoodaudio.co.uk/
I have two pair of Tannoy…some 3833gg from System 15 DMTii and some 12 “ 3149 pepperpots from LGMs.
These guys are usually pretty helpful with technical info including original crossover schematics if you join and ask nice…
https://groups.io/g/Tannoy
This is probably the most expansive resource online…
https://www.hilberink.nl/speaker.htm
There are some guys on here that are Tannoy fans if you poke around.
So, sometime in January I bought these classic 30 year old Tannoy CPA12’s after MZM identified the hidden treasures within: Dual Concentric 12-inch 3134’s. To top it all off, MZM has a ML box for these fitting my living room perfectly. And the price was unbeatable @ 500 dollars including an extra tweeter.
But, surprises kept coming. These pics show the drivers upon arrival at my house. Notice the baskets have been painted, and this had been spilled onto the surrounds and in some places also onto the cones.
One of the drivers have had a party with a lit candle. So, these are...