Anyone in London wants to team up for recapping / building Tannoy crossover?

[martinswimmer]

Hi, I live in SW London and would like to start some small diy projects mainly recapping vintage amps and building a new crossover for Tannoy MG. Anyone interested in polling resources? Best, Martin

[Puffin]

If I still lived in Battersea, I would. Sadly I am 40 miles away :(

[martinswimmer]

Oh, pity! I'm in Wandsworth, 5mins away from Battersea.
Do you have Tannoy DC? Any advice regarding crossovers?

[walpurgis]

Are you having problems with existing crossovers?

[Puffin]

Oh, pity! I'm in Wandsworth, 5mins away from Battersea.
Do you have Tannoy DC? Any advice regarding crossovers?

No Martin, I don't have any Tannoy's but am a demon with a soldering iron:D

[martinswimmer]

I've just bought Lancasters from late 60s and they look like they've never been touched. I was planning on keeping original crossovers as is and adding external ones. Energy switches don't seem to be doing much, rolloff works but i conclusively and i think that the left bass is weaker... any advice?

[martinswimmer]

No Martin, I don't have any Tannoy's but am a demon with a soldering iron:D

Double pity you don't live in Battersea anymore...

[Reffc]

I've just bought Lancasters from late 60s and they look like they've never been touched. I was planning on keeping original crossovers as is and adding external ones. Energy switches don't seem to be doing much, rolloff works but i conclusively and i think that the left bass is weaker... any advice?

I've rebuilt/refurbished many of these and the only way to do them properly is to dismantle them.

The switches at the very least require cleaning (use switch cleaner and work the switch back and forth as if you dismantle the switch, they never fit that well once pressed back together). Tannoy quality for caps was variable at best but the resistors are probably ok to leave alone. I'd replace all caps with better quality lower tolerance caps (3%). Along with switch cleaning, this will restore the sound to how it was meant to be.

Wiring was typically twin and earth lighting flex, non OFC. This can be improved upon using any reasonable quality 0.75mm OFC but you need to dismantle the existing joint to the 4 pin connector (be careful as it's easily cracked/damaged), desolder the original and replace. Use bi-wire 4-core and connect the negative wires together at the crossover end.

[martinswimmer]

Thanks, i was going to go down that route but thought it would be interesting to leave this one in and build another one (for example from troels gravesens kit) so that i can compare them afterwards. Would you know if any of the kits supply the autotransformer or do you need to source your own? ThAnks.

[Reffc]

Thanks, i was going to go down that route but thought it would be interesting to leave this one in and build another one (for example from troels gravesens kit) so that i can compare them afterwards. Would you know if any of the kits supply the autotransformer or do you need to source your own? ThAnks.

You would have to have an autoformer specifically wound if you wanted to retain the autoformer function. Sowters should be able to help. There is another way using fixed inductance but you have to modify the circuit to account for the autoformer effect on the shunt impedance otherwise you'll significantly skew HF response. Using fixed inductance does alter response a little, but with careful design and choice of components I actually prefer the fixed inductor versions. I am not aware of any DIY kits but there are a few (including myself) who have worked out the fixed inductor circuit values and can supply crossovers for just about any Tannoy.

I am prepared to supply this in kit form but there will be a lead in time for the kit to allow inductors to be ordered to correct values. You can PM me if you wish to go this route.

[walpurgis]

Your Tannoys are interesting.

Have you checked to see which drive units are installed. If they do date from the sixties as you say, they may have Monitor Reds in. Rather nice if they are and a valuable and appreciating asset too. Many people rehouse their Tannoy units in modern cabinets, but if you decided for the sake of authenticity to retain the Lancaster enclosures, much can be done to beef them up with bracing etc., to make them better usable.

[martinswimmer]

They are just Monitor Golds. Sound great but still experimenting. .. I'll keep these in Lancaster boxes.

[martinswimmer]

They are just Monitor Golds. Sound great but still experimenting. .. I'll keep these in Lancaster boxes.