Did Celestion Nail Audiophile Sound in 1982? No. But We Can Help!

[@TheMirolab]

Back in the 80's many tweeters were touted as having Ferrofluid for damping and improved power handling. Danny, what is your experience with ferrofluid in 30+ year old tweeters? My limited experience (of once) was with a pair of tweeters where the fluid was just sludge. They had removable diaphragms, so I was able to clean them up, and load them with fresh ferrofluid. This greatly improved their performance!! Could these Celestions be suffering from that? We don't see ferrofluid much in today's tweeters. Is this why? It seems we are doing just fine without the stuff.

[@johnm3544]

This seems likely. I'd wondered about ferrofluid too when he showed that appalling FR for the tweeter, it would never have left the factory like that.

[@jfritzy4358]

I refreshed the ferrofluid in mid 90's tweeters. A FR improvement, but still a downward slope beyond 15K then peak at 20K. Audible improvement so worth the effort.

[@danab7472]

My experience with ferro = wear surgical gloves next time.

[@HappyGeneRC]

I agree with lopping off the top, but what you've done with the response IS AMAZING!

[@genecase9464]

I agree but it's a shame about that big drop at the top of the tweeter though. But a recent hearing test at Kaiser told me I can't hear above 8K anyway so...😳

[@tg_ny]

Good speaker for a slightly older listener, you probably wouldn’t hear the issue with the tweeter since the frequency response of your own ears at the high frequencies declines with age. I remember listening to SL600s when auditioning loudspeakers, it was a nice sounding speaker. Perhaps not perfect, but very musical. Man, does the time fly…. Danny has a remarkable talent at getting the most out of just about any speaker. Pretty amazing.

[@davebutler3905]

Yes. My ears are limited to 10K now. Makes diy speakers easier... But only for personal use.

[@tommyshoe-star1426]

5:45 I almost spilled my coffee :O amazing work, as usual I love seeing the improved stuff (+ how and why you do this or that!) huge difference for sure

[@alexw890]

These would drive your dog crazy with that high pitched ringing!

[@RedSinter]

Well, Danny I'm kind if surprised you didn't swap out the Tweeter and fix that upper response.

[@scottmackey4182]

Danny doesn’t typically switch out speakers unless absolutely necessary. He tries to keep original components as the speaker was designed. Simply improving the signal output and cleaning up the frequency response typically does the trick.

[@hoth2112]

Danny did that with an original SL6 (with the copper tweeter) a year or so ago, but it became a custom one-off as it was a pair of soft dome tweeters we had on hand that fit the same screw holes. We try to avoid it when we can, but the customer had a very sentimental attachment to the speaker.

[@RennieAsh]

@@hoth2112 Could you put in a notch filter up there?

[@hoth2112]

@RennieAsh technically yes, but the parts value likely would be smaller than we stock, and pulling down a 15db spike is tough without creating a near dead short. The other issue was that the copper tweeter's output was ~3-5db below the average output of the woofer, which was the main reason we swapped out the tweeter.

[@gavinralph2910]

Fairly sure Celestion designed those tweeters 'in house' at great expense. Fairly sure they did the same tweeter but made of pure copper.......??? in another model. These were very highly respected speakers in the 80's and not cheap either! I I had a pair back in the late 80s but found the sound a bit 'small', maybe because of the closed baffle design and sold them for a pair of Tannoy's and was blown away by just how much detail I had been missing!

[@gino3286]

Fwiu the famous model was the Celestion SL600si the one with a aluminum honeycomb cabinet Spectacular 3d soundstage I would buy only the cabinet and use it for some kits The result could be fantastic

[@rontoolsie]

I bought a pair of SL 600 in 1984...cost around 800UKP, so very expensively. It was dull as dishwasher, squashed dynamics, no bass with muffled vocals. All with Audio Research electronics. The worst speaker I have ever owned. I managed to get the dealer to take them back and exchanged them for some Musical Fidelity electronics.

[@johnm3544]

@@rontoolsie I heard those speakers back then and was initially very impressed by their transparency (outstanding for that time) but then realised their efficiency was extremely low (to make the limited bass more apparent) and with a correspondingly lifeless sound. It seemed like Celestion had damped the hell out of them, so as to not put a foot wrong, rather than to try to do a few things right.

[@gino3286]

@rontoolsie hi thank you very much indeed for the very valuable advice Drivers selection comes always first The cabinet instead must have been a masterpiece The mid woofer is the critical part for sound Scan speak are good ones

[@danab7472]

I put a pair of Morel 448 into my Celestion Ditton 551s and they get along very well.

[@ornorra]

They had a 22Khz resonance so the crossover had a notch filter. Easy to google that

[@sidesup8286]

The Celestion SL 600 was the reference speaker of John Atkinson, the editor of Stereophile for many years. Mostly for its amazing imaging. I heard them many times and they were impressive in that way.

[@dannyrichie9743]

Hmmm, the parts that were used internally on these would sure smear eat up imaging.

[@sidesup8286]

I think you might be right.The SL 6 you have there is a different animal than the SL 600. Was not impressed myself with the SL 6 incarnations. But was impressed with the SL 600 and SL 700. The SL 6 used the same drivers as the SL 600, but that was about it. The SL 600 & 700 (both much more costly) than the SL 6 had I think a different crossover and definitely had cabibets made of Aerolam, a space age matwrial used in airplane jets. There was also a SL 6000 System, consisting of a pair of SL 600s, and a dipole subwoofer, with a forward radiating woofer and a woofer (not passive radiator) which radiated toward the back, in the opposite direction, in the same subwoofer cabinet..

[@trevorbartram5473]

Danny, you're being a little unfair. Forty years ago designers were not aware of parts quality other than adequate ratings. The high resistance of air coils was considered detrimental to sound quality.

[@rontoolsie]

@sidesup8286 I think the JA version was a limited silver edition...all the coils and internal wiring were made of pure silver. They may have resembled the ordinary SL600 on the outside, but the internals were very different.

[@sidesup8286]

Re: the claim that there was a SL600 special edition whose wiring inside was all silver wound. I serios doubt it. Silver wiring on a cartridge coils might be believable, but the expense to do that with both a speaker's coils and internal wiring would cost a fortune. Where can we read that such a model ever existed??...The Celestion SL 600 Si model, (which does not stand for silver), did have an update made, with attention given the ground returns, which on the original, shared the same connection part. You never know what info will pop up on here. Don't put belief in what you hear on forums. If there is any chance this could be true, please lead us to that info & source instead of "I think" or I "heard". Plus silver would not increase its imaging ability. About the only thing that silver wire adds is purity (if done right). and with silver wire you really have to know what you are doing. Some Audio Note amps are wound with silver and they cost well over $100,000. A lot of people read forums and their purchasing decisions are influenced by consensus. That is a very bad way to choose equipment. So amusing that the one guy out of the whole crowd, who goes against the grain and says something that a very heralded item sucks, is the one that is correct so very often.

[@stephenyoud6125]

great job again. See you next time

[@moviemakerkeith]

I own many of the SLs. To my ear I don't think they need to be changed. A couple things to note. Celestion went out of their way to use threaded inserts to secure the drivers with machine screws as opposed to using a wood screw into wood. The tweeter even being over 30 years old still sounds great because the voicecoil is wound directly on the dome making the dome act as a heat sink so no ferro fluid is needed. It's also worth noting that Celestion made the first ever metal dome tweeter (copper in the SL6/600) and then pioneered the aluminum dome. The faceplates have the vertical lines to break up the sound wave and minimize diffraction. The drivers were also analyzed with laser interferometry and are some of the best imaging speakers I've ever heard. The figure 8 brace was also added on the SL6S/Si models. Regardless of whether I think it needs upgrades, the response you managed to get is pretty remarkable. I'd be curious as to what Danny thinks is better - the Celestion SL6Si or the Paradigm Founder 40B.

[@dannyrichie9743]

Response levels aside, both of those speakers use pretty cheesy parts quality, and need a lot of help. You are not going to get great imagine out of the stock SL6/Si. If you think that's good, then you have not heard good. Our upgrade will dramatically improve it in those areas.

[@moviemakerkeith]

@dannyrichie9743 I bought a set of Kef LS50 Meta after watching your video. I find them to be on par with the SL series in general but I still find the soundstage and imaging on the Celestions to be better. Maybe im wrong. Im sure the SL6S is built to more of a price point than the SL700 crossover components wise, but its hard to imagine they use a very cheap coil for the woofer when they cost $300 each from the original manufacturer if ordered today (I can see why Celestion made their own in the 700SE).While I can agree the Kingston is better, I also don't think the SL series is very far behind them which I am lucky enough to be able to compare. I'd imagine those are classified as good. I think you could've at least given credit to the work Celestion considering the tweeters are some of the first metal dome tweeters ever made.

[@dannyrichie9743]

@@moviemakerkeith Well, for about the same price you could have just bought our X-LS Encore and completely blown away both of those models especially when it comes to imaging. The woofer coil in the LS6Si is a super cheap Iron slug type coil. They are about $6 each. The metal dome tweeters had a huge amount of break up and ringing at the top end, and the response was far from linear. I can't imagine any company accepting them.

[@moviemakerkeith]

@@dannyrichie9743 I'd love to do a comparison at home but the only thing I can offer you is to pay for shipping if you can lend a demo pair. I have binaural recordings of my speakers for subjective comparisons online for fun on my channel 3daudioxperience. I could add your XL-S Encore in the mix. I could even try or demo them with Celestions double dipole System 6000 subwoofers.

[@dannyrichie9743]

@@moviemakerkeith Where are you located?

[@sandwaves5642]

Had a speaker like this - with a sketchy tweeter.... Fixed it with an additional tweeter on the back ( not to ruin the "great appearance" ) 😀

[@pizzaearthpancakesandother2549]

wow this is the first upgrade kit that didn't include Norez. These boxes must be decent!

[@dannyrichie9743]

The upgrade kit includes one sheet.

[@dittonworks]

Hi Danny. Had the black (wet foam) internal foam disintegrated? If they have Poly caps? That’s SL6si (not signature model)

[@dannyrichie9743]

This is the Si model.

[@davebutler3905]

I'd be interested to see the response of the other speaker (of the pair) with that impressive new crossover. I wonder how wide the range of tolerance in those old drivers actually is. My Dad had Celestion Ditton 22s when i was a young lad.

[@dannyrichie9743]

Well swapping out the tweeters requires a whole new crossover design. We wee designing a new crossover for them anyway, so no big deal.

[@boris994]

Huge respect Danny! Thank you! Please, can you confirm that the black speaker seen on the table beside you is the SL6Si modelb and that it is the subject of this video? Thumbnail for this video is showing a pair of brown SL6 models which would have the Copper tweeter. SL6Si models had Aluminum tweeter.. SL6S was an in-between model and also had an Aluminum tweeter just as the Si And, yes, the high frequencies of even the Si models are very subdued but I do find the tone of the speaker to be hugely pleasant. And that the actual build quality is very good. They sure are heavy for the volume. Has this pair had the soldered harder, coarser internal wiring with only few strands opposed to modern fine multi threaded wires?

[@dannyrichie9743]

This is the Si version. My editor made the thumbnail. The wiring is typical PVC jacketed wire. Saying that the build quality is good is a stretch. The parts quality, crossover board, wiring, binding posts are all very poor.

[@hamidrezahabibi8111]

Magnificent as Ever🫵💎

[@JFord44]

York College? In York Nebraska?

[@dannyrichie9743]

Yes sir!

[@Kulumuli]

I'm really into english speakers. I was thinking a lot of buying a pair of Celestions in the old days but for my budget the Rega Kyte (the old ones) was better. The Kyte's are worth almost nothing these days but do rival most speakers up to $1000 today. I have a pair I don't use but I'm not just going to give them away to just anybody. I don't know how Danny would feel about those. Probably few of them in the US.

[@johnsmith-i5j7i]

Would love to see my celestion A range tested here

[@Kulumuli]

@@johnsmith-i5j7i I had to look that up. So, the A range is Celestion Woofers? Mostly for PA or also for home hi-fi?

[@edwinsim7206]

@@Kulumuli The A-series were after the SL series, after Kingston and after the ribbon 3000/5000/7000 models. The A-series A1, A2 and A3 were probably the last of high end home audio models Celestion produced.

[@ganck1147]

Heard the A-1 many years ago. They are very particular abt amp quality. I 1st heard them driven by Nad & what a disappointment. Totally flat & lifeless. Another salesman came in & brought the A-1s to another room where they were driven by VTLs & Gamut & WOW what a transformation. Its like listening to a totally different speaker.

[@viccooper6160]

The tweeter itself is still quite bad, Danny, so maybe a different package where the previously used tweeter alternative is included wouldn’t be a crazy idea?

[@emmet7208]

Show us the drivers out of the box, show inside the cabinet!

[@dannyrichie9743]

Thee wasn't much to see.

[@Ascoundrel]

ever encountered vintage IMF cabinets/speakers ? super compact i/ii , als 30/40, etc ... would love to hear your thoughts

[@IliyaOsnovikov]

Danny is it possible in such case to use a Low Pass filter at 20+ kHz for the tweeter and somewhat raise FR in the 15-18 kHz range playing with a Q factor of that filter? As I recall a certain combination of crossover parts can lift a "knee" near crossover frequency above driver's own output (without crossover).

[@dannyrichie9743]

I tried a few things on it, but it sucked out too much just below 20kHz. Most people won't hear it, some will....

[@tpop3723]

About to replace my crossovers but what damping material would you recommend?

[@dannyrichie9743]

For damping out cabinet wall resonances, nothing is better than No Rez.

[@tlpplacement9355]

Where were you 40 years ago when I started my first serious system? The Celestion SL Series was legendary in olden days, it was even worked on by an editor from Stereophile magazine. I duly bought a pair and was disappointed, they sounded dull. I replaced them with Dunlavy which was better. Real satisfaction came when I got the Usher Be-718 (designed by Danny), it let me forget about the hardware and focus on the music. There is still an active market in used Celestion SL's, even cross-over (of the exact same design) with better parts, nowadays. Unfortunately, these geriatric fans won't readily accept that Danny's re-design of the crossover will truly bring out the full potential of the Celestion SL. Never mind, most of these fans are in retirement age and can't hear the difference anyway.

[@gotchagoing4905]

I'm in my 70's and when, (hopefully this coming year) when I finally finish my shop I will buy one of dannies kit speakers and if I like what I hear, I will buy another set and have a great speaker X4 in my shop. I see no point in having a shop if it doesn't have a righteous sound system and this IS my last rodeo.

[@CharlesSheen-x6h]

Yeah just play a guitar solo on any speaker with treble up then sell it great strategy!

[@RennieAsh]

That's a Celestion tuning isn't it? Don't they go for that warmer kind of sound? It actually seems not too bad otherwise for an older speaker.

[@Ricky-cl5bu]

What if you have a perfect flat response speaker and you have a room that is bass light , would you not rather have a warm bass speaker, flat response speakers don’t always sound good , I build speakers to suit the persons room and tast ,end of

[@dannyrichie9743]

Being bass light happens much lower in range. In this case the whole lower range well up into the midrange was heavy.

[@Ricky-cl5bu]

Great speakers I like celestion

[@robertgreene2684]

Complete misunderstanding of what Celestion had in mind, It must be nice to live in a world where the only criterion is flat response, I like that myself, but other people have pursued other ideas. Obviously celestion KNEW the tweeter was down in level-- they wanted that

[@JBernhard72]

I really thought you where going to throw in a new tweeter and how the graph would improve.

[@rrd1975]

I wonder how many of these are still out there? Is Celestion still operating?

[@davebutler3905]

I think they still make guitar amp speakers for Marshalls.

[@benjaminthomas8092]

I bought this SL6 1Yr ago for 100.00 a pair I find no problem with this speaker system

[@dannyrichie9743]

The fact remains, they can be made a lot better.

[@D1N02]

Rolled of tweeter. The British sound..... I've got a pair of DL8's. Very slugish woofer... The crossover in there is a lot worse than the one in the SL6 Signature.

[@robtremble2277]

Hey there ya go

[@CashGravel]

Good Lord that’s flat

[@eriknielsen4924]

I got a center channel from celestion once was cheap and sounded cheap. Surprizes me anyone would want to upgrade any celestion product, figrede they used cheap horrible drivers, cheap construction and cheap crossover.

[@jasonwebb6484]

Like a lot of companies, there was Celestion (started in the 1930’s), then there was “Celestion” (when the company was sold to an invest firm in 1992). Generally, the speakers after 1992 are like ‘big box store’ specials & home theatre crap. They’re now known more for their guitar amp speaker drivers.

[@K-Mac_Racing_55]

You are lite up fine, but I cannot see the speaker very well. You need someone to fix the lighting in that room. Yes, I mentioned this a few times before, you even mentioned it, but still not fixed. Why? Buy more studio lighting gear.

[@dannyrichie9743]

We are building a new room for these. So it will be better soon.

[@Starch1b2c3d4a]

Its from 1982, ill give them a pass...

[@raymaksimavicius4902]

Danny why don't you ever show one of the most important specifications THE STEP RESPONSE that tells you if the speakers are phase accurate. Everything is phase accurate, amps are, preamps are, turntables are, wires are. Its only speakers that are not phase accurate except for Vandersteens. Danny start making phase accurate modes and show the proper step response which spikes up and then rolls off perfectly at a smooth 45 degree decay , each driver handing off their pass band to the next driver in phase.No dips or valley's. Come on man wake up for audio sakes!!!!!!!🤫

[@RennieAsh]

You think Vandersteen in the only "phase accurate" speaker? lol. Also, what happens when you stand up and move around.

[@dannyrichie9743]

RennieAsh is correct. Speakers like that are only in phase at one point in space. Moving up or down slightly changes everything.