It's always a good day when Kelvin uploads a video. My favourite UK hifi channel. Not least because I can actually afford the items you usually feature. Cheers mate.

And a perfect Sunday just got even better … another QUALITY UPLOAD by the main man himself Mr Kelvin we Salute 🫡 you Sir .. Thank you again for giving up your personal/ Private time to share the KNOWLEDGE… This is London Bermondsey calling 👍☮️👍

Great video! It’s good to see you don’t turn your nose up on the vintage equipment. I think vintage equipment can be highly rewarding!

Man, I love your videos. You explore the subject of Hi-fi in ways that are very relatable. In 2010, I rescued and restored a pair of Bozak b-4000 Symphonies from 1969. The cabinets were trash but the drivers had not been damaged. After a lengthy pursuit, I found a technician to recap the crossovers. I live in southeast Idaho, and had to go to Salt Lake City, Utah for this. The result was - and still is - a life-changing experience. I just wanted to restore them to as-built condition with no modifications. I play them on my Sansui AU-717 which I've lived with for 40 years and had rebuilt as well. I also love that vintage "thick" Sansui sound. I look forward to all of your future posts. Thank you and Cheers!

Hi Kelvin. I used to work just up the road from Cricklewood Electronics back in the early 80s for a cctv company called Merrion Security Systems, based in a huge house on the corner of Walm Lane and Shoot Up Hill, (the A5). Good to know that they're still there after 40+ years. All the best, mate.

Love the oil-change analogy,, 💖🥰💖

"when she smiled she said it all" such a great track

I did the same with my Mission Model 70 MK 2 and there was a slight difference, noticeable but like you say, doesn't change the fundamental characteristics.

Just recapped RCA (Radio Shack) speakers. Wow, wonderful cheap little speakers. Made a difference!

🙋‍♂️ THANKS KELVIN ,FOR SHARING THIS FOR THE AUDIOPHILE COMMUNITY 🤗😎💚💚💚

Your exactly right, alot of vintage speakers (and new ones after a few months) ive had to retighten the screws down because all them are usually loose.

Nice video, Kelvin! A while ago I rewired my 30 year old Mission 700s and replaced the tweeters, tightened the bass drivers. When connected to my primary system, playing some harpsichord music I was well pleased with the performance. Maybe I should re-cap them now! All the best, Rob in Switzerland

Nice one Kelv. Glad you did this in the end. It's funny how the capacitor on the tweeter circuit improves the bass. The woofer on those runs through an inductor only. It's all cohesive though. Never really liked Monacor caps. A bit hard for my liking. I always use SOLEN on these older speakers. Give the capacitors a good 20 hours playing and they will 'form' up and improve further. Well worth rewiring them to using decent copper cable. The old steel wire degrades the sound. Great video though. I've recently turned a pair of Ditton 15 into a compact BC1. Complete one off. They worked out really well. The series is on my channel if your interested.. Cheers. Matt

Thanks again Kelvin,much appreciated.You're one of my favorite vloggers in audio.

Been following this since COVID. he's the absolute best at this.

The only time you will hear a night & day difference is recapping speakers with a multitude of elcap capacitors. Had speakers that sound ok-ish when first arrived (monitor audio ma9). Sound deterioted over the course of months until the point i thought drivers were toast. Luckily not my main speakers but used at my bench for background music. So pulled the crossovers out. Every cap was reading miles out. So bought a big bag of new caps. Fitted new and speakers came back to life. Sounded like a new pair of speakers.

great video kelvin and for giving us a walk through in upgrading a speaker crossover and the positives from that thankyou😁

Excellent review / feature, etc, as always. Real world / everyman approach for those hoping to find their own path to audio nirvana. Always humorous & humane to those afflicted by the hifi bug. Solid advice without resorting to throwing shed loads of money at the problem. Big thumbs up 👍. ps. I agree with you 100% regarding Audio Gold, truly a very rare shop - I wish they were there when I started my quest for the perfect hifi set up 45+ years ago - would've saved me a lot of grief (and money).

Another smashed it out of the park film thanks Kelvin , every upload you make brightens my day 😊

Keep the vids coming Kelvin best hi fi channel on youtube .

A man after my own heart! Love your vids -thanks very much!

I recently recapped a pair of 1994 NHT Super Zeros I got in an auction. The crossover is mounted on a circuit board fixed to the back of the speaker terminal block. They used two electrolytics in the crossover and the replacement polycaps were 6 times the size. Of course everything was covered in hot glued and the original caps got dented during removal but amazingly still measured perfectly. I had to fit one polycap on the back of the crossover board and refit the terminal block upside-down to clear the woofer magnet.

Great video as always you’ve got me thinking about recapping my Snell speakers

Air core Inductors, polypropylene caps and non inductive resistors all make a difference. Polyethylene wiring and removal of all magnetic metal in the signal path is also good practice.

Hi again, mate. If you're ever down in South London, check out The Audio Centre in South Croydon. He specialises in vintage audio and on the premises repairs of all audio and video equipment. He's also won a few awards for servicing, especially open reel machines. Cheers again, fella.

Worth 10 nerdy measurement videos.

Thanks Kelvin - I'm going to have a go with some Celestion DL6s - bought the parts last week. Already rotated the woofer. 👍👍

Hope I find a pair of these this coming year.

Cheers for this Kelvin! I have some Ditton 15's that my Dad bought brand new back in '73. I have had them as my main speaker in spells over the past 30 years, on and off but now have them permanently, but semi retired, since his passing. And to be honest, I realise you aren't keen, but I do think these are one of those speakers that very much fall into the "subjective" category of liking them or not. No they aren't the pinnacle of hifi perfection, but for me, they were the sound I grew up with and I have a real, special bond with these speakers. Yes my Dali's and my Royd's are "better" speakers, the Royd's especially. But.....I could never get rid of the 15's as their sound to me hits so many emotional and sentimental spots for me. But....mine, as those ones were in the vid, absolutely standard and probably need all of the upgrades you mention here. So this was a very timely video. I shall seek out the bits, do the tweaks and give it a go! They might even come back into regular service again!

I seal the drivers in with a gasket it makes a good difference 😊

I've a pair of these Ditton 15 in my bassment. They were the rear speakers of my grandfather's setup, a Marantz 4270 with Dittons 66 on front and Dittons 15 for the rear. Yeah, remember, the years of the "Quad will be the future!" 😄 Today the 4270 and the 66s are in my living room as my day to day stereo. (I switched the 4270 to 2x70w). One of these days I will plug again these Dittons 15, I've an old Pioneer of the same period, they could fit in my studio as a spare "vintage listening system".

Many speaker designers would say don't change capacitor types as you are changing design. Couple tips beside usual measuring. Always do one speaker at a time to compare results. You can also use clip leads to compare sound of two types. Changing things can also change polar response so listen up and down or better measure.

Andrew Jones once gave away a design secret he learned at KEF…which is tighten the driver…and then loosen the screw a half turn. It reduced resonance by a measurable amount according to AJ

Thank you. i have a pair of realistic mach 2 speakers amercian 1984 need to refoam surrounds and a recapping. my kef 101 and 102 are old from 1990 and still great original condition really sound good. i must say the British make high quality audio.

If I can comb my hair I can recap a speaker. ..hee hee hee that's funny Kelvin cause I have no hair lol , Love the vids good sir and if you really want to improve those older speakers remove those terrible wood screws and replace with t nuts and bolt screws and consider the "Royd Audio "technology and use pvc pipe filled with anti acoustic caulking for dampening and put these behind each speaker driver having their magnets sit in the caulking as this will wic away all distortion that starts in the magnet ...I have done this to my B&W V201s and it made a remarkable improvement and I haven't even touched the crossover yet...seriously recommended as the improvement is cheap and very effective also change the internal wire to a better quality preferably solid core and make sure they are soldered in and not plugged in ...have a great day Kelvin

This is exactly what I wanted to know

I remember doing a similar capacitor "upgrade" back in 1995 using a Solen audio grade polypropylene capacitor. Musicality and detail improved in an almost magical way given the relatively modest cost of the Solen caps at the time.

Kelvin, totally agree on recapping. Didn't do it on the speakers since all the paires that I own are fairly new but on vintage receivers and amplifiers - both pre and amp sections. Started with a Sansui AU 217 to see if it will be "better" afterwards. A bit more power and clarity on tone controlls. A lot more to say on this but I will stop since is a controversial topic.

Changing an Alcap for a film cap will probably slightly change the sound signature anyway as they would have been voiced using Alcaps. Would’ve been interesting to have tested the original cap’s ESR and capacitance with something like a peak esr70 to see if they were out of spec and if so how far. I’ve had mixed results when Ive replaced old caps sometimes better but sometimes “thinner” sound.

Thanks

did set of wharfedale e50's - totally cleaned up the midrange which was recessed and flat / dull sounding . still not fully there though so suspect the 30 year old amp may be next .

Hey Kelvin, your now on the vibe, Monocor is a respected company and I've changed the character of a few speaker systems using there reasonably priced products .. cross overs .Enjoy the music..I do every day. For your Fans there's a stunning album they should here.. 'A common thread " songs of the Eagles.. Enjoy my friends ..❤ god bless you all, brothers and sisters... And everything In between..

Kelvin, another fantastic video. What about 80's speakers review?

Better parts always help, higher grade resistors will be an audible upgrade for a few dollars a few braces would help.

Considered putting new caps in my AR18Ss... tested the old ones and they were still in spec.

I have a crossover upgrade kit for these that go beyond a re-cap.

If your recap, use capacitors with the same ESR and capacitance. Small changes in resistance can throw off the original crossover design. If your speakers are old enough for a recap, the crossover is very likely not very good, so you might design your own. I recently did that with my Ohm L speakers. The original crossover was total crap.

Brilliant nice job.

With some research one could even upgrade x-over caps aside from just replacing what was there and really level up the SQ.

Hi Kelvin. Thanks again for a REAL opinion on HiFi. You are the most genuine reviewer I have ever seen.

Hi Kelvin. Check out a guy called Yves Carbonne and his albums; Seven Waves and Tales Of The Reconstruction. Much respect. Andy

Brilliant 😊

Car oil change was a good analogy.🎉

Good channel 👍

Try BangOlufsen S70 , with capacitor renewed in their sweetest spot .

An easy job when the components are nice and accessible! Beware some speakers where it is very hard to access the crossovers.

Nice! I prefer doing one first, then doing an A/B L/R comparison, using a mono signal of course.

Very nice presentation! Here in NEW England USA, I know a pair of MATHMOS lamps when I see 'em ! (O:

Kelvin,there must be some modern speakers that do the business. Like to see a few of those!

think you figured out my climate controlled '93 Cerwin Vega 120s sounded so much better than a a pair I had around the same tine that were used outside in a barn and stored in a garage. Foam surrounds were both good, but the sound was completely different . he caps were probably bad in the outside pair stored in the heat and cold.

I always hated the Ditton's back binding posts. These are incredibly easy to replace too, with some solid banana plug terminals if you prefer that. Also, Haycross Audio on KZfaq is worth a visit if you're into vintage speaker recapping. He's a British fellow that has done a ton of these including a one off build for the Celestion Ditton 15's.

Hi Kelvin! I had the Celestion 120. Maybe the same as Ditton 15? It has the same tweater and passive radiator. And it had the sweatest midrange I have heard. But you have to have them up om the wall. Not in free space.

treble provides the edges to the bass and this gives more definition and attack.

I suggest you test the old capacitor Capacitance. If it's not 12yF (give or take a few percent), It's faulty and needed to be replaced anyway. If it is with in range, well now were entering the land of snake oils and Psychoacoustics which is also interesting.

Nice experiment. I possibly would have just changed like for like on the cap, as polys can make older Ditton’s sound a bit hard.

Really interesting vid. I've recapped a few pairs of speakers and my experience is very similar, but as I understand it (and i may well be wrong) in a simple crossover design, that capacitor is essentially just a frequency filter (my own terminology) that protects the tweeter from receiving the whole, potentially damaging, frequency range. I am therefore puzzled why this would make the bass sound better? Perhaps its just the general fuzziness of the frequencies sloshing around the drivers that disappears when fresh caps are introduced? If someone more knowledgable could enlighten me I'd appreciate it!

I would be scared to recap JBL L19 speakers though.

Grab a free copy of the Room EQ Wizard ... and you can easily measure the difference.

Did you measure the drift in capacitance of the old caps you removed? NPE caps do drift / wander over time. In anycase replacing with PP will provide longevity

nice video Calvin... I am going to buy a pair of Tannoy Arden Mkl👌before there are no more...have you heard them...what brand is the lava lamp?

Did you consider recapping just one of the speakers? It might be easier to judge any change that way, although I suppose each speaker could sound slightly different to begin with!

I have a recapped sansui au 101 and a pair off spendor bc1 both a big improvement on before you just need to find a good professional didn't cost me much 60 quid for the amp 200 on my speakers great video but I'm crap at soldering 😅😅😅

What you said about bass changes proves that what you have heard is only placebo. It is not possible to anyhow affect bass response by changing the only capacitor in the crossover, because it is tweeter capacitor and no smallest amount of the signal goes through it to the woofer driver. Unless you had a air leakage and fixed that by rescrewing the terminal plate to the enclosure, or changed something similar, it is 100% placebo.

I wonder how an electrolytic capacitor would have sounded instead of the polypropylene...maybe you could do a comparison?

I recapped my dynaudio speakers with mundorf resistors & some fancy Mundorf supreme’s, I didn’t notice a difference tbh

I don't understand how the bass can be affected by the new capacitor? The fact that there are two coils and a capacitor in the crossover, indicates that the tweeter has a second-order filter (coil and capacitor) and the bass a first-order filter. So, changing the capacitor cannot affect the base!

A frequency sweep measurement graph would have been better. Sure you can tell the difference with your ears, but how much of a difference is impossible to know for us viewers without a graph, or some kind of scientific before/after graph. On-Axis, Off-Axis, bass related cabinet ringing (Decay), crossover points and peaks and valleys. Just saying "It sounded better" is something I say after cleaning the wax out of my ears, not after making electronic changes to gear.

so how would a capacitor give the speaker more bass ? since it's job is to protect the tweeter and cut off low frequencies ? how did you hear more bass ? maybe when you tighten the screws ?

Did you let the caps break in?

Hi Kelvin. I've been repairing hifi for some 35+ years now. I don't like to be critical but that capacitor only serves the HF1300 tweeter along with an inductor as the high pass filter. There is one inductor on the bass driver which is the low pass filter. I find it hard to believe that changing that capacitor can have any effect whatsoever on the bass and/or how deep it goes. Tightening the screws yes, but changing that capacitor cannot effect the bass as it is not in the bass circuit. 🙂

Kelvin, any relation to Christian Horner of Red Bull F1 fame?

Was the capacitor in the low pass filter to the woofer or the high pass filter to the tweeter?

North London? Gunners or Spurs?

I wonder how replacing a capacitor gives you more bass since it is very likely in the tweeter circuit. So it's function is to filter out the lower frequencies to the tweeter. I've seen this behaviour reported before in a capacitor replacement.

more bass how? that capaciitor is only filtering low frequencys from the tweeter... you can put the same capacitor, the new capacitor, or have no capacitor at all, and the bass driver will play the same.... the bass driver does not even see that capacitor in the circuit... maybe the tweeter is so much clearer now that makes you think the bass is better too.. its the 'new oil' effect..

UNfortunately, there is now proof in this video, SOUND CLIPS ARE REQUIRED.

If you are going to recap, use as expensive parts as you can afford, if you want it to make a real difference, also in older speakers replacing the internal wiring which will be crappie is worthwhile. Some quality OCC copper, litz if you can or even silver will make it even better. Replace iron ferrite core inductors for air cores of the same values.

Thanks!

Nice one Kelv. Glad you did this in the end. It's funny how the capacitor on the tweeter circuit improves the bass. The woofer on those runs through an inductor only. It's all cohesive though. Never really liked Monacor caps. A bit hard for my liking. I always use SOLEN on these older speakers. Give the capacitors a good 20 hours playing and they will 'form' up and improve further. Well worth rewiring them to using decent copper cable. The old steel wire degrades the sound. Great video though. I've recently turned a pair of Ditton 15 into a compact BC1. Complete one off. They worked out really well. The series is on my channel if your interested.. Cheers. Matt