Refoam your speakers - centering of the cone in a simple way.

[@mikeoleksa]

Just a follow up. This worked perfectly on a pair of Boston Acoustics A60 and HD7 speakers. I glued the new foam to the cone first and then I was able to realign the voice coils without removing the dust caps by moving the center using the tension provided by the clothespins to hold the cone in place and pushing down lightly on the cone until I heard no rubbing (or whatever term you want to use for the noise and feel you get when the voice coil is off). Thank you again for this. A simple, yet effective, way to do this more confidently. It was my first refoam project and I'm very happy with the results.

[@audiofriends254]

Good morning, Thank you very much for your reply. Good the speaker are back! Much pleasure with listening! Best regards, Fred

[@keithrandall9469]

Thank you for this video! I never refoamed speakers before and was a bit intimidated by other centering methods I saw. I tried this and it worked perfectly. The speakers sound great again! The only thing I did differently was to use 4 small clamps rather than clothe pins, but the clothe pins would certainly have worked.

[@audiofriends254]

Good morning, good the repair went perfectly. Comments, replies and questions are always welcome. Very much pleasing listening to you renewed speakers :-) !

[@nikoholopainen6926]

This looks very promising! I think i have to try this method 😎👌🏻

[@jebus1166]

Watched a few videos of how to do this. Others just have you glue the whole thing and "work it" center while the glue is still wet. I like this approach better. About to give it a shot. Thanks for the idea.

[@audiofriends254]

Good afternoon, First thanks for the reply. We think the voicecoil should be as much as possible in the center. And that is not possible by just pushing if the voicecoil runs free. I’ve translate (just with Google) an old Dutch pdf of me out of 2006: www.repairyourspeakers.com/manuals/+English/reasons%20to%20center%20right.pdf I think pure to center right, shimming is a solution, and with a ±35 Hertz signal. For shimming you need new dustcaps. But a new dustcap sounds different as the old original. A dustcap (if the dust cap is made from hard/solid material like paper) brings the higher frequencies of the woofer, certain with smaller woofers. Also this method is not always possible (Dynaudio/Tannoy etc.). If you use the old dustcap it still may sound different because of the glue in between the dustcap and the cone, and it’s often not a nice picture. Centering with a 35 Hertz signal is possible, but (most at small drivers), the lead wires may obstruct a decent centering. Also the equipment necessary is not always available. We like to show a good centering with simple tools, so that much people get inspired to do the job. I hope I did answer your question, I tried. Questions are always welcome. Best regards, Fred

[@mikeoleksa]

GREAT IDEA!!! I just bought some clothes pins from Amazon with Prime shipping even. Thank you!!!!

[@dejanmaksimovic665]

Bravo majstore iskreno svaka casttt.

[@douglashague2355]

Gonna try this on a pair of Electro-Voice EVsix's and a couple advent loudspeakers, seems like it's going to make the process a lot less frustrating

[@audiofriends254]

Good afternoon, thanks for your friendly reply. On our list of possible ways to repair your speakers with new surrounds, we have also some video's linked, just from others with for instance 'shimming'. Of course we tried to search for the best video's from others, and placed the links on: www.repairyourspeakers.com/en/repair-videos/c-1. With best regards, Fred.

[@audiofriends254]

What are the other possibilities for centering the cone / voice coil? - Shimming: Is a good way of centering, but has some disadvantages. With some speakers it’s impossible to remove the dust cap, for instance with the the Dynaudio 24W100 series. Also with an expensive Tannoy dual concentric speaker the value may become lower if after the shimming the mounting of the new dust cap can be seen. But that’s not the only disadvantage. You have three choices: 1. Use the old dust cap. We think in this case the best solution. But… certain with small woofers from about 8 inch and smaller, the dust cap has often a function of sound reproduction of the higher frequencies of the woofer. Also when you use the old dust cap, you will make a glue layer on the place were normally the sound transfer was with other material. That could easy change the sound produced by the dust cap. 2. Use a new dust cap witch is special made for the speaker like Cerwin Vega. Good, but if the replacement can be seen, and wil devalue the speaker. 3. Use another dust cap. Is a solution, but most times the dust cap has to be from a large diameter than the old. This wil also affect the sound reproduction in the high frequencies. If above can be heard? That depends on the speaker. I must say that if the job is really proper done, and the speaker looks really like new, it might be a good solution. It’s more work and you will have to be more handy than centering with our method. - Frequencies 20-40 Hertz (about 35 Hertz most times used)(see KZbin). Is a good possibility. Only (especially at small speakers like from the Bose 901) the lead wires will change the direction of the cone / voice coil. If this is the case, the speaker will be not well centered. Disadvantage is that you need often some more equipment to do the job proper. - Centering by the spider. Is possible, especially with small speakers with a strong spider under the cone. First check if the cone is well centered by the spider, and mount the surround on the frame crosswise. Best regards, Fred

[@pitbullcoachingvideowall-e3773]

with this speaker it's easy cause you just have to follow the line in other case i open the cap kzbin.info/www/bejne/bXKbfmt-mdOaiZI here is the master

[@-IE_it_yourself]

cool idea

[@CatSoft]

Great video, interesting method. However, I used a 50Hz low level volume to center the cone. You can hear immediately if the coil is rubbing against the magnet.

[@audiofriends254]

Good morning, I think you’re completely right. The only problem is often the equipment for this trick. We like it to make it in a way that it’s not easy to find the right tools. We have a good tone generator, but the more simple way to connect a mobile phone to an amplifier should be possible, I also have seen on KZbin videos were the phone is direct connected with the speaker. Actually I don’t know if then the speaker can be tested on a higher volume, and if the volume of the phone is enough to center the voice coil. We like to make a video about this (and other). But to make a good video is actually some long work. Can you tell if you used an amplifier or connected right away the mobile phone to the speaker? Maybe you have a tone generator or a long sweep on a cd-player. Thanks in advance, Best regards, Fred

[@CatSoft]

@@audiofriends254 I have used a cheap amplifier (from eBay - Lepai) and a little oscilloscope - SainSmart DSO138 - $22) that I had in the house from other projects. As a tone generator I used my phone with one of the many free apps available. I started playing the SINE 50Hz and adjusted the volume on the amplifier until the oscilloscope (connected to the speaker terminals) was showing 1Vrms or 3.14Vpp. That moves the cone not too much, but enough to self center it. Then I just pressed the foam surround (pre-glued) opposite each time so it didn't disturb the self centering. It might be a somewhat complicate setup for someone not inclined to electronics, but it really helped me revive some really old 8" speakers (1987) from an Roland piano HP-5500S.

[@audiofriends254]

@@CatSoft Thank you for your perfect explanation! I would like to make a video by myself. Have to find some time. I have the equipment, but the trick is to make it as reachable and simple for most people. Best regards, Fred

[@pitbullcoachingvideowall-e3773]

with this speaker it's easy cause you just have to follow the line in other case i open the cap kzbin.info/www/bejne/bXKbfmt-mdOaiZI here is the master

[@audiofriends254]

@@pitbullcoachingvideowall-e3773 For your information: www.repairyourspeakers.com/en/repair-videos/repair-with-tone-generator/c-160.

[@HowardEllisonUKVoice]

Great. But what do we do if the spider needs re-centering, and the dust cap can't be removed to apply shims?

[@audiofriends254]

Good morning, first thanks for the reply. That’s indeed a job that I didn’t have done before actually. But I think the problem can be solved. Take old negative film like in video kzbin.info/www/bejne/gYjdaK2rmMeEmMk. Then cut these over the length in 6 small stripes from approximately 5 mm. Dismount the spider. It is accurate work so please take your time and have enough light. Big light spot on it. Then take plastic tweezers (Google) and put the negative film crosswise in the gap between voice coil and upper metal plate. So first 3 crosswise, than the other 3. Now glue the spider again with a strong glue between the stripes of negative film on just 3 spots if the spider is small, on 6 spots if the spider is large in diameter. Wait till the glue is at its top strength. Than pull out the small stripes of negative film. Tale a blunt knife to lift the not glued parts of spider. Glue them well with the same glue. This should solve the problem. Note that I’ve never been in this situation and that its accurate work. All at own risk. Best regards, Fred

[@mikeoleksa]

You can figure out if the voice coil needs to be aligned quite easily by simply pushing down gently on the cone. You'll hear the rubbing. This method allows you to move the cone in the small increments quite easily if needed. Also holding it in place without worrying about messing up the glue. There are MANY instructional videos that actually recommend against removing the dust cap and it's unnecessary.

[@Grubdissimo]

I know it's not essential to these types of videos but I'd love to see the finished product play some tones though it. Kind of gives the viewer the pay off

[@audiofriends254]

First thanks for your reply. Actually the other Bose 301 still has to be refoamed (shame)(I’m quite busy :-) ). The used foam surround (type 8"A-10) is flexible and should give a deep good bass punch.

[@Grubdissimo]

@@audiofriends254 that would be great. I'm about to do my first speaker refoam with a Boston acoustic sub so I have been binging these types of video's

[@audiofriends254]

P.S. Audiofriends had the first clothes peg manual before KZbin, already in 2007: www.audiofriends.nl/pdf.

[@schipbreukeling3]

In clothes pegs we trust? also the new ones from China? But great video and manuals

[@centaurus777]

Looks like a winner if the dust cap cannot be removed.

[@Alan-megan]

nice

[@gregglockelect]

What is the glue used to stick the foam?

[@audiofriends254]

Good morning, thanks for your reply. The glue we use can be found with information on: www.repairyourspeakers.com/en/glue-brush-syringe/glue-for-foam-rubber-surrounds-1-x-15ml-best-tested/a-1675-11. With best regards, Fred

[@audiofriends254]

Surrounds, glue, brush, repairkits (also Kurt Müller) also in English, German and Nederlands on www.repairyourspeakers.com (PayPal, creditcard, Sofort, iDeal, etc.), and on eBay.

[@shubhamdalvi3992]

Why centering is essential for rubber punchered??

[@audiofriends254]

Good afternoon, I myself think that with small perforations (for example by a cat) no centering is necessary. It is somewhat dependent on the speaker itself, but it can happen that the rubber, or still intact foam surround, is released from the cone or the frame. If this is over a large piece, for example larger than 1/3 of the total diameter, I would personally center the cone to be sure. Kind regards, Fred

[@audiofriends254]

You can buy foam / rubber surrounds, glue, brush or repairkits at www.repairyourspeakers.com (PayPal, creditcard, Sofort, etc.). Check our quality at www.ebay.com/usr/audiofriends.

[@malcolmwearin4185]

I didnt do this and it hasnt worked out for me. Speakers sound crackly. Do you not put glue on the centre to stick to the cone?

[@audiofriends254]

Good morning, you mean 'shimming'? That's an opportunity, there are a lot of video’s on KZbin. Note that the dustcap has a function in certain frequencies. Of course different with a 2-way speaker system with a small woofer/midrange than with a 30 cm. woofer. See also www.repairyourspeakers.com/index.php?action=extra&extra=A_15__het_stofkapjes_verhaal_&lang=en. If you already have glued the surrounds, and the speakers sound crackly, it’s a good time to find out if the speakers are well centered or the voicecoil for instance is damaged. If you place the speakers on their backside - so that the weight of the cone has no influence on the repair - push around the cone on the roll of the surround. You will while pushing on the roll replace the cone a bit. Go all around the cone and listen good if there is a place where the crackly sound is less. That’s the way the cone should go. If this is the case, it is possible - carefully and with patience - to dismount the surround on the frame bit by bit with a small screwdriver. Our glue is an industrial glue so actually not easy removable as PVA is. Next is to recenter the cone again. I hope you have something at above story, you may also e-mail us at [e-mail] .

[@malcolmwearin4185]

Thanks when i press on a certain part it does sound better. Unglued cone and it sounded better already without being glued. Will try recentre it again though.

[@davidbkelly]

You did not show how to do the hardest part of getting the foam on the cone.

[@audiofriends254]

Good afternoon, we have the complete version on: kzbin.info/www/bejne/mKC5hoWYmtlkZ8k.

[@audiofriends254]

Critical comments or questions are welcome!

[@flyurway]

So exactly wtf did you do??? If there's one thing I can't stand it's silent videos like they're done by mutes. That and trying to watch what's going on while reading captions! The title says "with sound" so open your mouth and SPEAK and TELL me wth you're doing. So you fumble around doing something with the cone, fumbling with clothespins, listening for something obviously...TALK and tell me exactly what the hell you're doing. Those of you commenting below about how this worked for you, you all must be mind readers because I haven't the slightest clue what he did. And I've even done these before!

[@audiofriends254]

Good morning, First thanks for your reply. English is your native language, and also the most used language in the world I’ll guess. But if possible I like to have the instruction video available as much as possible for more people with different languages. In my case German language is also important. I would say, even without English text and without a spoken word: the video shows the way. Further, the whole world is reading subtitles, so why can’t you? If I speak - witch isn’t my native language of course - I actually think it’s more confusing than subtitles. And, often - for instance if you listen with a mobile phone in public - it’s not possible to understand the voice, unless you play the sound hard. It’s a choice, other instruction video ‘s are indeed English spoken. But nevertheless an idea. See also www.google.com/search?q=sub+tittles&oq=sub+tittles&aqs=chrome..69i57.1878j0j8&sourceid=chrome&ie=UTF-8 Best regards, Fred

[@donmoore7785]

You sir are clueless, if everyone else had no problem. Don't you see that?