RFC Monitor Gold Custom Crossovers

[montesquieu]

Apologies for stepping into this thread. I don't have Tannoys or a need for new XOs. Just interested.

Maybe I'm being too simple about this but why the need to design new XOs? Surely an easier way is to simply grab the original schematic that Tannoy had and make a new XO with modern parts based on that schematic? If Tannoy did not publish the schematics then simply copy from an existing XO?

I suspect I'm missing something simple here and will soon be informed.

[non-technical explanation coming up] The original Tannoys use autoformers that enable switching for different sounds (rolling off treble for example). These work ok but have their limitations and are in any case difficult to reproduce. Replacing these with custom inductors removed the switching ability but offer potential for improved sound - better clarity mainly but also better bass response.

You can get very good results from recapping the originals and putting in better resistors - they were manufactured down to a price and in any case are 40-50 years old now - but there is benefit in getting rid of the autoformers, so long as the circuit is correctly devised to manage the change. Some duff circuits circulating have put some people off going down the crossover replacement route (I got caught myself with this some 6-7 years back) but Paul's of course don't suffer from this.

[Edward]

Ah thanks Tom. So all down to taking autoformers out of circuit and getting that right.

I need to research (aka google) autoformers.

[cooky]

If you want to go active this(red) is the Monitor Gold voltage drive curve you need to follow-with most modern digital crossovers this is pretty straightforward.;

[montesquieu]

If you want to go active this(red) is the Monitor Gold voltage drive curve you need to follow-with most modern digital crossovers this is pretty straightforward.;

Yes looks familiar, I had some help to set them up but passive still sounded better.

[petrat]

Thanks, Tom ... interesting to hear your experiences of active vs X-overs. ATM, I agree with Geoff about Tannoy's original X-overs sounding pretty fine in mine, but your comments about using autoformers do strike a chord with me. Maybe it's time to open them up and find out what is actually in mine

[cooky]

Yes looks familiar, I had some help to set them up but passive still sounded better.

Not all DSP crossovers are equal or capable of preserving all that lovely valveless in your system, I've used XTA and ALLDSP units with excellent results on Tannoy Arundels but it's certainly a more challenging route. One look at those curves against the raw response of the drivers and it's plain to see how easy it is to alter the stock voicing-passive or active..accidentally or on porpoise.

[walpurgis]

As long as the switches are clean and in good order, there's no issue with them. The autoformers in themselves are not a problem. The really fussy, can bypass the switches. I'd not bother.

You can uprate the power handling of crossover components, but to what end? Tannoys were designed for use in high level professional situations and the crossovers are well matched to that requirement in terms of power handling.

[montesquieu]

I’m not by any means saying the originals are rubbish. Only that the overall sound can be improved. It’s not subtle either the improvement is obvious.


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[WESTLOWER]

I purchased some early Tannoy 12" Monitor Golds, in Chatsworth sized cabinets, here on AoS. The crossovers they came with were original Tannoy HPD315, so whilst they made the speakers sing, you could tell there was more to come from these drivers. I was advised by a few from this parish to contact Paul Coupe at RFC www.referencefidelitycomponents.co.uk as he was the go to for Tannoy crossover advice.

Paul was very generous with his time both on phone and email and advised me that although the drivers were playing music with the HPD crossovers, they were not right at all and whilst they'd make a noise they were a long way off...

After visiting Tom's (montesquieu) place and hearing for myself what a well thought out and executed crossover design could offer I was hooked!
I contacted Paul again and he took me through the options, not once strong arming me into a purchase, indeed trying I felt, to save me dosh..

I made my selection, external crossovers in birch ply boxes and went for the components one down from the reference level...and formed an orderly queue.

The long and short of it, a few weeks later 2x very well packaged and extremely well made boxes arrived with a cable fitting kit, exactly the same as the photos earlier in this thread (i will add my photos later) and a simple clear and straight forward instruction email. First visual impressions were good. I was impressed with the external build quality.

i installed the Crossover cable connecting kit and fired up the Amps...

I suppose we all long for those moments of trepidation, expectation and excitement of a new toy in our systems to give us that 'upgrade' lift. Well buying effectively blind, I had all of those feelings.

From the first note I could hear a stratospheric difference in the speakers. Everything seemed to come into focus. The low end bass had definition, timbral beauty and grunt (oomph), the whole presentation had changed for the better. Gone was the rather shouty middle to top on vocals and horns, replaced by a smooth transition which moved seamlessly into the extensions of the higher frequencies.
There was more presence and whilst very impressing it's extremely easy to listen to. 6 Hours later I was still there. I loved it.

I'm pretty bad at articulating this sort of thing but I feel compelled to post about the biggest 'upgrade', change i have heard in my system.
I really like what I hear. I simply can't wait to go home tonight a listen again. And i guess thats the litmus test, right?

Anyone contemplating 'upgrading' their Tannoy crossovers, Paul is your first port of call. if you are worried about buying blind, you are more than welcome to stop on by my gaff and enjoy what this UPGRADE has done to the music presentation. I make good coffee.
Music is very important to me and Paul's product has just helped to give me more joy.

(btw i have NOWT to do with Paul, professionally or socially)

[anthonyTD]

Nice to read another positive outcome, from a happy customer!
A...

I purchased some early Tannoy 12" Monitor Golds, in Chatsworth sized cabinets, here on AoS. The crossovers they came with were original Tannoy HPD315, so whilst they made the speakers sing, you could tell there was more to come from these drivers. I was advised by a few from this parish to contact Paul Coupe at RFC www.referencefidelitycomponents.co.uk as he was the go to for Tannoy crossover advice.

Paul was very generous with his time both on phone and email and advised me that although the drivers were playing music with the HPD crossovers, they were not right at all and whilst they'd make a noise they were a long way off...

After visiting Tom's (montesquieu) place and hearing for myself what a well thought out and executed crossover design could offer I was hooked!
I contacted Paul again and he took me through the options, not once strong arming me into a purchase, indeed trying I felt, to save me dosh..

I made my selection, external crossovers in birch ply boxes and went for the components one down from the reference level...and formed an orderly queue.

The long and short of it, a few weeks later 2x very well packaged and extremely well made boxes arrived with a cable fitting kit, exactly the same as the photos earlier in this thread (i will add my photos later) and a simple clear and straight forward instruction email. First visual impressions were good. I was impressed with the external build quality.

i installed the Crossover cable connecting kit and fired up the Amps...

I suppose we all long for those moments of trepidation, expectation and excitement of a new toy in our systems to give us that 'upgrade' lift. Well buying effectively blind, I had all of those feelings.

From the first note I could hear a stratospheric difference in the speakers. Everything seemed to come into focus. The low end bass had definition, timbral beauty and grunt (oomph), the whole presentation had changed for the better. Gone was the rather shouty middle to top on vocals and horns, replaced by a smooth transition which moved seamlessly into the extensions of the higher frequencies.
There was more presence and whilst very impressing it's extremely easy to listen to. 6 Hours later I was still there. I loved it.

I'm pretty bad at articulating this sort of thing but I feel compelled to post about the biggest 'upgrade', change i have heard in my system.
I really like what I hear. I simply can't wait to go home tonight a listen again. And i guess thats the litmus test, right?

Anyone contemplating 'upgrading' their Tannoy crossovers, Paul is your first port of call. if you are worried about buying blind, you are more than welcome to stop on by my gaff and enjoy what this UPGRADE has done to the music presentation. I make good coffee.
Music is very important to me and Paul's product has just helped to give me more joy.

(btw i have NOWT to do with Paul, professionally or socially)