Crossover refurb

[brian2957]

1106711068

I have a pair of Rega EL8 floorstanders which I absolutely love . I was wondering if it was worth refurbishing the crossovers as the speakers are over 20 years old . Just looking for any suggestions from the experts on here . Thanks.

[YNWaN]

To be honest, I doubt it. It has an air-core inductor for the tweeter and a good quality ferrite core for the bass. I don't recognise the capacitor but I don't think it is an electrolytic. The whole thing is neatly hard wired (no circuit board) - there isn't really anything to do.

[brian2957]

Thanks Mark , just wondering if it was worth changing the capacitor or doing anything else.

[YNWaN]

Can you take a closer picture of the capacitor? If it isn't an electrolytic it won't have aged. You could replace it with something more exotic, but there's no guarantee it will actually be any better.

[brian2957]

I'll do it in the morning when the light is better Mark . Off to Ali Taits gaff tomorrow to listen to his new turntable and some battery powered amps and Dacs . So will post sometime tomorrow . Thanks Mark.

[istari_knight]

If its anything like the ELA it will be Ansar Supersound MKP... If its anything like the Kyte it will be a cooking grade MKT.

[brian2957]

Thanks James , if mine are either of these should I replace them and if so any suggestions ? EDIT : They do have MKT stamped on them , don't know if this is of any help .

[YNWaN]

ClarityCap ESA or Mundorf Supreme would be my choice.

The MKT is still a polypropylene capacitor though.

[istari_knight]

Sounds like they are similar to Kyte crossovers - I guess the MKT caps are blue ? I keep hearing good things about Clarity Caps ESA but am yet to try them... Alternatively, Ansar Supersounds are a safe choice.

http://www.hificollective.co.uk/components/claritycap_esa.html
http://www.cricklewoodelectronics.com/Cricklewood/home.php?cat=155

[brian2957]

Thanks gents , I'll give some a go and get back to you.

[YNWaN]

A 4.7uF ClarityCap ESA is £5.38
A similar MCap Supreme is £20.42

[brian2957]

Bliddy hell :eek: Looks like it's the Claritycaps Mark. Cheers.:)

[YNWaN]

No prob - Falcon Acoustics are your best bet for them (cheaper than hi-fi collective).

Oh, A single 4.7uF Duelund Cast capacitor is £309.12!

[337alant]

(MKT) stands for Metallized Polyester and is a film cap, change for a good polypropylene (MKP) as others have stated
Have a look at Reffc thread about xover capacitors

Alan

[YNWaN]

Yes, sorry - had my doubts as soon as I wrote that it was polyprop.

[Sovereign]

Looking forward to totally transforming my covers when I get some time off over Christmas, Brian your covers look positively simple compared to my birds nest
http://i1138.photobucket.com/albums/n533/SovereignKing/IMG_5286.jpg (http://s1138.photobucket.com/user/SovereignKing/media/IMG_5286.jpg.html)

[YNWaN]

Covers? - you mean crossovers?

Looking at it, yours appears to consist of three capacitors and three inductors - with two of the capacitors made from multiples?

[brian2957]

Looking forward to totally transforming my covers when I get some time off over Christmas, Brian your covers look positively simple compared to my birds nest
http://i1138.photobucket.com/albums/n533/SovereignKing/IMG_5286.jpg (http://s1138.photobucket.com/user/SovereignKing/media/IMG_5286.jpg.html)
Aye James , if it looked like yours I doubt I'd be tackling it .

[brian2957]

(MKT) stands for Metallized Polyester and is a film cap, change for a good polypropylene (MKP) as others have stated
Have a look at Reffc thread about xover capacitors

Alan
Thanks Alan , are the MKT type of caps prone to deterioration over time ?

[brian2957]

I've just ordered some ClarityCap ESA capacitors . Thanks for the advice chaps . I'll post some feedback when I get the chance to fit them :)

[YNWaN]

Thanks Alan , are the MKT type of caps prone to deterioration over time ?

Nope, not really.

[brian2957]

OK thanks Mark . I've bought the ClarityCaps now so I'll give them a try .

[YNWaN]

£10 isn't much for a fun experiment and the CC is technically a better capacitor.

[brian2957]

Yup you're right Mark . The last time I asked for advice on here I refurbished the crossovers on a set of Royd A7s and I got some excellent results. So here's hoping.:cool:

[YNWaN]

If you wanted to push the boat out you could also replace the bass inductor for an air-core type. The problem is that it would be quite a bit bigger (over twice the size) and significantly more than £10 - it depends what mH value it is?

[Sovereign]

Covers? - you mean crossovers?

Looking at it, yours appears to consist of three capacitors and three inductors - with two of the capacitors made from multiples?
Yes your right , the joy of predictive test from a phone.
Brian I have to admit that without Paul at Reffics help I wouldn't know my bum from my thumb .

[brian2957]

If you wanted to push the boat out you could also replace the bass inductor for an air-core type. The problem is that it would be quite a bit bigger (over twice the size) and significantly more than £10 - it depends what mH value it is?

Thanks Mark , I think I'll keep it simple for the moment and change the caps first . If I get an improvement I'll have a think about it . Will the mh value of the inductor be marked on it ?

[YNWaN]

It might be - but it might not (they aren't always).

[brian2957]

As I have very little technical know how I think I'll leave well alone for the moment then Mark. :D

[istari_knight]

I had thought the EL8/Kyte crossovers were similar [I have all of the Kyte inductor measurements] but your HF cap is 4.7uF whereas the Kyte's is 7uF so we can safely assume everything else is likely to be different too. These are surprisingly accurate & cheap too http://www.ebay.co.uk/itm/LCR-INDUCTANCE-CAPACITANCE-RESISTANCE-METER-w-Lead-DE3-/140980098418?pt=UK_BOI_Electrical_Test_Measurement _Equipment_ET&hash=item20d3119572 should the bug bite :)

[Reffc]

If you need any assistance Brian, just shout and I'd be happy to help advise if needed. Shame I didn't see your posts earlier as I had some Jantzen Superior 600V 4u7's going spare.

As for the inductors, if you know what drivers are used (their specific details) and can supply me with the capacitor values used, I'll be able to confirm what the inductor values should be for you.

[YNWaN]

The drivers are specific to Rega - If he gave them a call I'm sure Rega would tell him the value of the inductors.

[istari_knight]

If you need any assistance Brian, just shout and I'd be happy to help advise if needed. Shame I didn't see your posts earlier as I had some Jantzen Superior 600V 4u7's going spare.

As for the inductors, if you know what drivers are used (their specific details) and can supply me with the capacitor values used, I'll be able to confirm what the inductor values should be for you.

Now there's an offer you cant refuse :eyebrows:

As Mark points out its Rega's own RR125 with a modified Vifa D20 [rear chamber added.] The Kyte uses a 2nd order HF: 7uF in series & 0.4mH/1R in parallel / 1st order LF: 0.6m/0.5R in series.

[Reffc]

Now there's an offer you cant refuse :eyebrows:

As Mark points out its Rega's own RR125 with a modified Vifa D20 [rear chamber added.] The Kyte uses a 2nd order HF: 7uF in series & 0.4mH/1R in parallel / 1st order LF: 0.6m/0.5R in series.

Thanks James.

I'm taking an educated guess that the modified rear chamber is to lower resonant frequency allowing a slight lowering of the typical x-over point for that tweeter. The little air core suggests that the HF is 2nd order and the LF is a simple first order. There isn't any impedance flattening (zobel) and the crossover slopes are quite shallow. Personally, I would change the electrolytic out for a poly and leave it at that. I am investing in some specialist measuring gear that will give me all of the Thiele parameters for any driver, and without knowing the impedance curve, resonance point, inductive equivalent and similar data for the mid/bass, it's impossible to recommend any further upgrades or changes which would simply be a stab in the dark. Bear in mind that swapping an electorlytic for a poly WILL alter the ESR (equivalent series resistance) for the cap, so you may need to introduce a small padding resistor to avoid unwanted lift in the treble. It's a pretty crudely design x-over tbh and probably could be bettered but that depends on whether you intend hanging onto them or just want a straightforwards like for like refurb.

[Welder]

Hello Brian. :)

I don’t want to piss on the parade and all that but……………..

If the capacitors aren’t out of spec (you can test this with most decent multi meters) then despite the “this cap sounds better than that cap” rather optimistic chaps on the hearing department I would say you’re wasting your money and time.
On the other hand, if you wanted to tweak the speakers a bit, better internal bracing and some more extensive deadening panel work might just give some audible benefits.

Of course, lots will disagree with me but I’ve found it’s the design and cabinet build that makes a good speaker; not handfuls of oil and diamond filled caps and gold wires. ;):rolleyes:

[Reffc]

No-one is suggesting gold plated caps, just that electrolytics are the worst possible to use in crossovers in the signal path and far greater linearity can be achieved using polyprops. Due to the age, and the fact that a poly cap costs about £4 for the value needed, that's an eminently sensible piece of advice. Stiffening the cabs is also a good idea but it largely depends how far Brian wants to take this.

[brian2957]

:)
I had thought the EL8/Kyte crossovers were similar [I have all of the Kyte inductor measurements] but your HF cap is 4.7uF whereas the Kyte's is 7uF so we can safely assume everything else is likely to be different too. These are surprisingly accurate & cheap too http://www.ebay.co.uk/itm/LCR-INDUCTANCE-CAPACITANCE-RESISTANCE-METER-w-Lead-DE3-/140980098418?pt=UK_BOI_Electrical_Test_Measurement _Equipment_ET&hash=item20d3119572 should the bug bite :)
:) Well I could buy it James , it's what to do with it that's the problem :scratch:

[brian2957]

If you need any assistance Brian, just shout and I'd be happy to help advise if needed. Shame I didn't see your posts earlier as I had some Jantzen Superior 600V 4u7's going spare.

As for the inductors, if you know what drivers are used (their specific details) and can supply me with the capacitor values used, I'll be able to confirm what the inductor values should be for you.
Thanks Paul , I'll change the caps first and try that . I was thinking about internal bracing improvements also . I can handle a bit of basic woodwork but I'm afraid anything other than very very basic electronics is way beyond me . If I decide to go any further I will certainly contact you if that's OK . Thanks for the offer BTW.

[YNWaN]

Adding decent bracing is difficult to do once the cabinets are glued together - especially if the holes for the drive units are not very big (as in this case).

[brian2957]

Point taken Mark . What about some kind of bitumen sound deadening panels or 3mm steel plates .

[YNWaN]

Yeah, steel plates were used in a similar manner by Royd.

[brian2957]

Yup , I know Mark . I had a pair of Minstrels but I prefer these Rega EL8s in my system so I'd really like to try and get the best from them if I can ( within reason of course) .

[istari_knight]

IMO an imagined improvement is still an improvement ;) in this case spending £10 on some caps is hardly anything to worry about... If the OP were considering caps in the £££100's I would have advised against it as I'm sure would anyone sane.

Change the caps, have a listen then maybe try some deadening :) FWIW Rega still use this exact crossover design for their current range.... Heres an R3 crossover:

http://www.kanpai-club.ru/foto/hifi/rega/crossover.jpg

[brian2957]

Aye that looks like the EL8 crossovers. The bass units on mine looks exactly like the bass unit on the RS3s although the latter uses 2 of them . Not sure about the tweeter though . Cheers for that James. :)

[YNWaN]

Yup , I know Mark . I had a pair of Minstrels but I prefer these Rega EL8s in my system so I'd really like to try and get the best from them if I can ( within reason of course) .

It wasn't meant as a criticism Brian - I think you should do it.

[brian2957]

Sorry Mark , I didn't take it like that :) . I did like the Minstrels but thought the EL8s worked better in my room .' Horses for courses' mate . I've discovered that one of the crossovers has broken up inside the speaker ( parts have come adrift )so Paul at REFFC has kindly agreed to have a look at them and carry out any refurbishment / repair work for me ,so I'll be sending them off to him this week . Watch this space.

[istari_knight]

Sorry Mark , I didn't take it like that :) . I did like the Minstrels but thought the EL8s worked better in my room .' Horses for courses' mate . I've discovered that one of the crossovers has broken up inside the speaker ( parts have come adrift )so Paul at REFFC has kindly agreed to have a look at them and carry out any refurbishment / repair work for me ,so I'll be sending them off to him this week . Watch this space.

Probably the ferrite cored inductor... At least that's what came away in my Kytes & half unwound itself in the process ! ... I notice they use added cable ties these days ;)

[brian2957]

Yup I think that's it James . Plus the board everything is mounted on has come away from the plastic piece which holds the binding posts and screws to the body of the speaker . So not good and probably a bit beyond me so I've asked Paul to have a look at them .

[YNWaN]

The curse of hot glue - it's crap really.

[brian2957]

Well it's held things together for almost 30 years Mark . D'ya think it might work on me :lol:

[The Grand Wazoo]

Big bracing through a little orifice?
Try my method.......

http://imageshack.us/a/img191/4529/durt.jpg

[istari_knight]

Yup I think that's it James . Plus the board everything is mounted on has come away from the plastic piece which holds the binding posts and screws to the body of the speaker . So not good and probably a bit beyond me so I've asked Paul to have a look at them .

:thumbsup:

I'm sure Paul will have immense fun removing the drivers... The air was blue when I did mine :eyebrows: ... They are glued in, yes I kid you not... GLUED !

[brian2957]

I'm only sending the crossovers to Paul . If that's the case I may just leave the drivers where they are James . We'll see , I'll take the screws out and give it a try.

[YNWaN]

Well it's held things together for almost 30 years Mark . D'ya think it might work on me :lol:

Depends how much you use I guess... ;)

[brian2957]

Prolly need quite a lot mate.

Sent from my GT-S5830 using Tapatalk 2

[istari_knight]

I'm only sending the crossovers to Paul . If that's the case I may just leave the drivers where they are James . We'll see , I'll take the screws out and give it a try.

Best of luck to you :)

On the Kytes I had to remove the crossover/connection panel by prising with a flat head screwdriver, the using some mop stick against the bass drivers magnet assembly beat it out with a hammer... Even then it took far more force than expected. If theres a Rega dealer local it would be worth a visit as I'm told they have a special tool :eyebrows:

[brian2957]

Thanks James there's a couple of Rega dealers in Glasgow . I'll try the crossover refurb first then take it from there.

[peter j]

Having used Ansar caps a number of years ago and being very happy with them,I recommended them to a friend recently who was up-dating a Tannoy crossover.
This wasn't a deeply technical up-date,just a straight forward like for like cap swap.The use of ultra high expensive caps was ruled out due simply to cost.
We weren't sure if they were still available but found them at a company in Clitheroe called Suppression Devices.(Thanks Google).
Disregarding some of the hyperbole thats associated with audio descriptions it's sufficient to say that they sounded darned good.They also cured the main problem he had which was instruments drifting between the speakers depending on the frequency being played.As a bonus they don't cost a fortune.

[The Black Adder]

Ansar caps are really good, a nice match with Tannoys too for a like for like swap from the original Plessy ones.

[brian2957]

Thanks chaps . I bought some ClarityCap ESAs and the crossovers are on their way to Paul as we speak . Watch this space .:)

[brian2957]

Thanks chaps , I bought some ClarityCap ESAs and they , and the crossovers, are on their way to Paul as we speak. I don't know if you can see from the photo , but the crossover was in bits . The crossover base had come away from the plastic housing which holds the speaker posts and the inductor had come away from the base and had begun to unwind itself . The crossover was vibrating/rattling inside the speaker when music was played . I thought it best to leave well alone and gave Paul at Reffc a phone . He spent almost an hour on the phone with me discussing my requirements and offering me options for refurbishment and repair . I've dealt with Paul before and his service and quality are outstanding .
Watch this space.

[The Black Adder]

nice one dude. ESA's are very good indeed

[brian2957]

Thanks Joe . I really like these little floor standers , they seeM to fit my room perfectly . They did need repaired , however, if I can get a small improvement in SQ at the same time I'll be over the moon .

[The Black Adder]

Thanks Joe . I really like these little floor standers , they seeM to fit my room perfectly . They did need repaired , however, if I can get a small improvement in SQ at the same time I'll be over the moon .

Cool!...:)

The ESA caps will need time to break in but after a while the sound just starts coming through and simply gets better over time. Not too long with the ESA's either. The MR's which are the next step up take much longer I found.

Great!.. It's always nice to get something you love updated and Paul will do you very well indeed.

Keep us updated.

[brian2957]

Will do mate.

Sent from my GT-S5830 using Tapatalk 2

[Reffc]

Will do mate.

Sent from my GT-S5830 using Tapatalk 2

All done for you Brian. I've sent photos to you to check you're happy with the end result. Will be sent back tomorrow for you.

[brian2957]

Looks fantastic Paul . Thanks for spending so much time with me explaining the ins and outs of this crossover refurbishment . Really appreciate it . Watch this space :)