Tannoy Monitor Gold Crossovers

[Ammonite Audio]

Some time ago I came to the conclusion that the autotransformer in the Tannoy Monitor Gold crossover circuit was there for good reason, eg often a 'lift' in treble energy is required.

http://www.troelsgravesen.dk/MG15XO_files/MG15-XO_small.jpg

This makes replacing the original crossovers rather tricky, since these autotransformers are not available nowadays and a 'best guess' value has to be applied to a parallel HF section inductor that takes its place.

A little while back I contacted Sowters about making a new replacement and they have now told me that it's possible to recreate the original item in terms of the inductance of the autotransformer taps, DC resistance etc. The cost is going to be just short of £80 each, which is perhaps not bad value.

I'm going to order a pair of these autotransformers to try out with my Lancasters and shall let you all know how I get on.

[Marco]

Most interesting, Hugo! Others and I will be very interested how you get on, so good luck :cool:

Marco.

[The Black Adder]

Update on this thread...

Thanks to Hugo I will be giving these autoformers a spin in my Crossovers designed by Nick... Will let you know how I get on.

[Marco]

When are we gonna see the updated pics of your system, Joe, which you've been promising for AGES?

I'm dying to see what your Lockies look like! :)

Marco.

[simonms]

Ditto, just about to transplant some Autotransformers into my Westminster cross overs which were also made by Nick as i am finding them a little recessed in the HF area-very interested in your findings-i think you will be pleased as i think they are there for a reason, I think treble "energy" is what is lacking at the moment with my speakers but the cross overs still need a bit of burn in....oh and my front end is crap, but only until the weekend:)

VB Si.

[The Black Adder]

Will certainly post up the findings. And yep, Marco... will get some pics sorted soon... I like to tease. :eyebrows:

The Lockwoods are looking and sounding magnificent.

Simon, matey your Westies are my next port of call..I want some but I need a bigger house first... lol

I agree, the autoformers must be there for a reason so we shall see. Of course they will need a little burn in though I suppose.

[simonms]

Will certainly post up the findings. And yep, Marco... will get some pics sorted soon... I like to tease. :eyebrows:

The Lockwoods are looking and sounding magnificent.

Simon, matey your Westies are my next port of call..I want some but I need a bigger house first... lol

I agree, the autoformers must be there for a reason so we shall see. Of course they will need a little burn in though I suppose.

Let me know if i can be of any assistance, there is a lot I have learned about these speakers through building them, more than meets the eye, and they are still not finished to my satisfaction. More cross over tweaks and listening needed. I have had a lot of people over from forums and a couple of ex. Audio Note employees and get e-mails the next day saying, "my speakers sound narrow" etc.(Wilson Benesch and Avent Garde owners).
Am in Brighton if you are ever down for a visit:)

VB Si.

[The Black Adder]

Let me know if i can be of any assistance, there is a lot I have learned about these speakers through building them, more than meets the eye, and they are still not finished to my satisfaction. More cross over tweaks and listening needed. I have had a lot of people over from forums and a couple of ex. Audio Note employees and get e-mails the next day saying, "my speakers sound narrow" etc.(Wilson Benesch and Avent Garde owners).
Am in Brighton if you are ever down for a visit:)

VB Si.

Cooool Si!.. Will do.

LOL... well... From what I can hear with the Lockwoods the sound is certainly not narrow so I can imagine that your speakers really cooked their noodles...

I guess getting an idea of which 'general' or typical tapping the Tannoys run with could be good for a start. I guess I will find out but something to reference to might be good.

Nick will be showing me how to go on with these later so I think we should have some news on the outcome in the next couple of days.

[Wakefield Turntables]

Joe,

Are you still running your lockwoods with your Quad II's or Croft gear??

[The Black Adder]

Joe,

Are you still running your lockwoods with your Quad II's or Croft gear??

Hi Andrew.

No I'm now using Croft 25 with the 7R+ amplifier, a special build from Glenn to suit the Tannoys... well cool!!!

The Quads are for sale at Audioflair. - I miss em but the sound from the 7R really moves some air... yummy! :eek:

[Wakefield Turntables]

I may be joining the Tannoy brigade soon, watch this space ;):D

[simonms]

I may be joining the Tannoy brigade soon, watch this space ;):D

Tell us more, I have just bought a Sugden Masterclass phono same as you.

How do you find it?

VB Si

[Wakefield Turntables]

Well its a bit complicated but I always wanted two systems. A top notch SS and Valve system (you can see these in my signatures). Currently I have some Celestion Ditton 44's that I've been using as the speakers on my Valve system (I also have some Quad ESL57 One Thing Audio modified), but i have ALWAYS had a hankering for some Tannoys. It looks like I may be paying a semi decent price for a pair, hence joining the Tannoy club!! The SS system gets updated from time to time, mainly with upgrades to the 1210 to which its the primary source of the SS. The valves have a Garrard 301 as its primary source, which at some point this year is going to be fettled by Dominic at Northwest Audio ;). The SS system is completely silver'd up in that everything from the plugs/IC/RCA's even the SUT (when it arrives) is silver whilst I intend the valve system to be a purely copper based system (Some Tellurium IC's and speaker cables will be coming soon). I intend to do the external cross over mods to the Tannoy's. Then I think I need a rest! hope this explains everything.

[Magna Audio]

Why not do away with the level switch and have a master volume & bi -amp?
Each amp can be set to your vol choice and you can benefit from the 'right' type of amp for the LF (typically biggish PP valve amp) and the 'right' amp for the HF (typically a sweet little SET valve amp).
You also benefit (by quite a margin in my experience), by getting rid of the resistors that do the attenuation on the AC signal to the drivers.

I recently demoed a Bi-amp set up on a pair of GRF cabs to a chap who was quite amazed at the difference it made.
This was a nice PP 20W KT88 amp used as normal single amp, and then the same amp on LF and a EL84 SET on HF, to compare.

[The Black Adder]

All done.. Great results.

Ta.

[vencel]

Hi Andrew.

No I'm now using Croft 25 with the 7R+ amplifier, a special build from Glenn to suit the Tannoys... well cool!!!

The Quads are for sale at Audioflair. - I miss em but the sound from the 7R really moves some air... yummy! :eek:

Hello Joe,

Finally you sold your Quad IIs? Are the Corfts that much better?
I also talked of myself from the Quads and I am going to build an Atmasphere OTL amp. Hopefully I can start the project soon (it's all matter of money).