Tannoy eaton mods?

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Tannoy eaton mods?

Post by Graeme » Mon Dec 07, 2009 8:43 pm

Been listening to my tannoy eatons (hpd295a drivers, the 10" ones).

They seem very good but im sure they can be improved.

So, as stock the box is 20.5"x 15 3/4"x 93/4".

this is the stock crossover

and these are the T&S parameters

Voice coil resistance, Re: 5,8 ohm
Free air resonant frequency, fs: 26 Hz
Moving mass, Mms: 34,4 gm
Electrical Q, Qes: 0,26 -
Mechanical & Acoustical Q, Qms: 2,2 -
Total Q, Qts: 0,23 -
Force factor, Bl: 11,2 N/A
Total suspension compliance, Cms: 1,1 mm/N
Equivalent volume compliance, Vas: 200 Litre
Mechanical resistance, Rms: 2,55 Mechanical ohm
Effective radiating area, Sd: 360 sq. cm
Sensitivity (2.83V@1m, 20 deg. C): 91,2 dB

Im wondering what to do though.

Should i leave them bone stock?
Just replace the connectors, binding posts and re-wire?
Worth bypassing the crossover controls? (i set them to 'level')
Maybe better crossover components or a new crossover?
I came across this crossover design, i think its for the 10's rather than the 15's

As for cabinets, ive found some info on new box sizes but is it worth it? Tannoy cant have got it that wrong can they? They will be used in a room around 12 foot square.

If i keep the stock cabinets, is it worth adding some internal panel damping?

The only other thought i have is about the baffle. Its inset by about 1/2". Modern thought is thats bad right? If i keep the stock cabinets would it be worth making a new baffle to fix over the origional, beveled around the driver/port to overcome the edge lip?

I know nothing about these and all the info i find is for 12's or 15's.
Anyone got any thoughts?


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Post by planet10 » Wed Dec 09, 2009 4:46 am

That 2nd xo was one recommended by a fellow on the joelist (my drawing)

With yours you could do the standard cap/resistor upgrades and once you have settled on the switch positions you should bypass the switch.


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Post by Graeme » Wed Dec 09, 2009 6:29 pm


Im thinking i may be best off just upgrading the crossovers.

Might build some similar cabinets, but out of better materials.

Should i upgrade all the corssover caps?

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Post by mdotpasq » Mon Dec 30, 2013 10:03 am


I'm just wondering how you got on with your Eaton modifications?

I've just picked up a pair for a great price in lovely condition - already with the rubber surrounds, and by the looks of it very light use (1 owner from new!)

I feel like I want to get a little bit more air and sparkle from them on initial listen - especially in comparison to the SGM 12X's I use daily.

Did the crossover recap make a big difference? If so what did you use? How about rewiring?

Also, the connections on the back are quite low down, and it looks difficult to fit in anything else without a bit of modification..
Any info about what you have done would be greatly appreciated.


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Post by Graeme » Tue Sep 09, 2014 5:49 pm

Caps helped but the main issue is the cabs. They sound alot better in bigger, more open cabs

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Re: Tannoy eaton mods?

Post by rocknrollben » Sat Jul 02, 2016 3:46 am

I am new to the forum and want to replace the hf capacitor in my Tannoy Eatons.
I have purchased the parts 4.5 uf capacitors but as I took the crossovers out I do not know how to identify the part to unsolder and remove.
I have soldering skills but I do not know how to read the schematics.
Can someone please help me to identify which part it is so I can complete the task?

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Re: Tannoy eaton mods?

Post by Phil Y » Thu Jul 14, 2016 8:37 pm

Hello Ben,

If you look at the diagram, the +ve input to the crossover only goes to 2 places, the first (of 3) caps in the treble section and the series inductor for the bass section. Simply follow the track from the +ve input and you will find it, it is the one that is not an inductor !

As you give the value of the cap as 4.5uf (i assume you mean 4.7uF) then that must be the first cap as that value is wrong for the others.


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