• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Diatone DS-35B mkII surround dilema

Donald&Lydia

Donald&Lydia

Member
I have owned a pair of semi-rare Diatone DS-35B mkII speakers for a couple years now but have not been able to truly use them. They have a rolled cloth treated surround that has dried and hardened to the point of being cracked . With the speaker being a sealed enclosure this will not work.
I have searched and searched for correct replacement surrounds ( ebay , yahoo japan , hifido , etc.) but cannot find anyone anywhere that makes a rolled cloth surround. I can put a foam surround on but would really prefer to hear them as they where intended to sound. Will putting a foam surround on them change the sound characteristics of the woofer?
I was able to purchase replacement woofers from a set of Mitsubishi DS-20 speakers that have the same part # , same cast frame but have a different albeit correct to mitsubishi cone on them. My issue with them is the outside trim piece is a little different color than the original diatones , different cones and their surround are rock hard as well , although not cracked.
Does anyone have an idea where to find 1/2 roll cloth surrounds ? Does anyone know of a doping product that will soften the surrounds that does not involve rubbing random petroleum products on them ie. brake fluid , trans fluid , leather conditioners etc. ?
The first photo is the speaker with the Mitsu woofer in it , the second is a closer view of mitsu woofer , third is original Diatone woofer. Any help or suggestions would be appreciated , i am beginning to lose hope that these can be correctly fixed. ThanksIMG_0820.JPG IMG_0828.JPG IMG_0825.JPG
 
Last edited:
Register to hide this ad
Hello botrytis ,
The cones themselves are in excellent condition. The surrounds are my issue , will using a foam surround change the performance of the woofer? The original is a large roll leading me to believe that the woofer must have had some extension when the surround was supple. I do not want to use foam but if there is no other viable options i will.
Thanks , Richard
 
Hi,
I have a similar situation with a pair of Yamaha ns4 monitors. I can get the surrounds in foam, but not in the original butyl. Anyone out there have any idea how much change can be expected from such a change as Donald&Lydia has described?
 
Its a tough one Rey1 , i have been searching again today down every rabbit hole i can find for an answer and cant find anything definitive.
Richard
 
Thanks botrytis, thats what i was afraid of. I guess being that i have never heard what they truly sound like , i can find a foam with the closest specs to the original surrounds as i can and see what happens. Maybe a crate of original surrounds will pop up some day and i can redo them properly. LOL
 
I have the same speakers, though in worse condition. I think brake fluid might be the solution, and perhaps I'll try it. You are right that the speakers seem very bass deficient. but I'm not sure that its just the surround that is the issue.
 
Nat said:
I have the same speakers, though in worse condition. I think brake fluid might be the solution, and perhaps I'll try it. You are right that the speakers seem very bass deficient. but I'm not sure that its just the surround that is the issue.
Click to expand...
FWIT, it has been going on five years now that I've used DOT3 brake fluid on my JBL L15a Lansaloys with what I consider a great degree of success.
 
I did try brake fluid , trans fluid and a boot waterproofing gel on the worst original woofer. It was dried and cracked beyond repair so i felt i had nothing to lose. They did soften it a little but not to the point where i thought it would be an option for the Mitsu drivers. I may end up just replacing them with foam.
 
I may do the same. The foam will have different characteristics than the original surround, but the spider affects compliance more than the surround (or so I understand) and the current surrounds' characteristics stink, so different will probably be better.
 
Thats my thoughts Nat. I can always redo them in the proper cloth surrounds if they become available but at least i can use them in the meantime. The build quality of the speakers are excellent and by all accounts sound great so i am really looking forward to getting them up and running. Now to figure out how to get that ring off of the outside of the surround , i have never seen one sealed up this tight.
 
I'm in the unfortunate/fortunate position of having a pair that encountered so many dome-pushing-in-exploring-fingers that there is really no making the drivers worse looking. And there are no grills. So I can do anything I want to these without affecting the resale price.
 
I am VERY familiar with those speakers and really like them. Foam will lower the fundamental resonance a bit; no biggie IMO. Be careful at first, they will be easier to bottom. A subsonic filter might be a good idea if you like to play them loud, as well as a one amp fuse in series with the tweeter as replacements are hard to find. I replaced a lot of those tweeters with Dynaudio D28s for LA mixing engineers back in the 80's (with a small bleed off resistor) when the originals became NLA and every one of them preferred them that way.
 
audiomagnate said:
I am VERY familiar with those speakers and really like them. Foam will lower the fundamental resonance a bit; no biggie IMO. Be careful at first, they will be easier to bottom. A subsonic filter might be a good idea if you like to play them loud, as well as a one amp fuse in series with the tweeter as replacements are hard to find. I replaced a lot of those tweeters with Dynaudio D28s for LA mixing engineers back in the 80's (with a small bleed off resistor) when the originals became NLA and every one of them preferred them that way.
Click to expand...
Thank You audiomagnate ,
That is exactly the info i needed and coming from someone with direct hands on knowledge makes it all the better.
Richard
 
Hi all. Relatively new member here - mostly lurking, reading, learning... Richard, I've used the AR/KLH woofer surround sealant from ebay seller vintage-ar on some hardened late 70's Mitsubishi (Diatone) MS-30 (6Ω/150W/30~20000Hz) & MS-20 (6Ω/120W/35~20000Hz) doped cloth woofer surrounds with some degree of success. What seemed to work best was applying the doping/solvent thoroughly albeit sparingly to both the inside & outside of the surround. I found that a 2nd or even 3rd application after a month or two while also driving the speakers (sometimes with a low frequency tone generator) and working the surround (with fingers) helped. Time & patience is key; don't try to work 'em too hard, too fast. I even used a hair dryer to heat the surround slightly before applying the solvent which perhaps helped it enter the cloth matrix and made it easier to work the surround. Additionally I used toluene to slightly cut the AR doping so less dissolved-sticky-butyl-rubber (the sealant) is applied.

There's not much to lose trying this softening approach first, especially if you're considering re-foaming anyways.

I have a set of 1984 Diatone DS-3000 (6Ω/180W/25~40000Hz) waiting in the wings for the same sort of treatment and these Mitsubishi's have been the test subjects. The DS-3000 surrounds aren't quite as hardened as the MS-30/20 so I suspect the treatment will work even better. Can't wait to hear them with supple surrounds...

-Brian
 
Last edited:
Welcome to AK and thanks for your input Brian. The surrounds on my Diatone DS-35B mkii were severely dried out and had multiple cracks on one ( the other is just as dry but not as many cracks). I ended up putting in a pair of woofers from Mitsubishi MS-20s , they have the same part # and cast aluminum basket but have a different cone material . I will be buying the sealant from vintage-ar for those and my newly acquired Mitsubishi / Diatone DS-50cs . I just purchased a DA-A15DC amp , DA-P10 pre-amp and the Mitsubishi DS-50cs a few days before Christmas and have been VERY happy with them.
I did remove the surrounds from the DS-35Bmkii woofers but was unable to find new foams that matched the rather odd dimensions of the cones and baskets. I talked to the folks at Van L Speakerworks near Chicago and he assures me that he can custom-make surrounds for me , he has been building speakers for 40 years .
These Diatones are fantastic speakers , really a shame that they did not " catch on " here in the states , their revered in Japan and rightly so. Your DS-3000s are beautiful !
Thanks for the Tip , Richard
 
Donald&Lydia said:
Thank You audiomagnate ,
That is exactly the info i needed and coming from someone with direct hands on knowledge makes it all the better.
Richard
Click to expand...
If you replace your surrounds with foam please send me some pics and update us as to how they sound. I have a pair of ms-20's with good original surrounds that have been a part of my main listening space for over a year now and i can assure you these speakers have plenty of tight accurate low frequencies. Not boomy speakers by any means but also not base deficient. A real solid classic rock speaker.
 
HiFiAaron said:
If you replace your surrounds with foam please send me some pics and update us as to how they sound. I have a pair of ms-20's with good original surrounds that have been a part of my main listening space for over a year now and i can assure you these speakers have plenty of tight accurate low frequencies. Not boomy speakers by any means but also not base deficient. A real solid classic rock speaker.
Click to expand...
I will do that HiFiAaron , It may be a couple weeks , more projects than time and money. I am blown away by the sound of both pair of mine.
 
Those DS-50s are pretty rare. I stumbled into a pair at an estate sale a few years ago which restarted my old interest in hifi. I haven't looked closely at the surrounds in a while, but they where perfect at last viewing. Not sure what the surrounds are made of, but I'd think hard before putting something on them.
 
Lo-Fidelity said:
Those DS-50s are pretty rare. I stumbled into a pair at an estate sale a few years ago which restarted my old interest in hifi. I haven't looked closely at the surrounds in a while, but they where perfect at last viewing. Not sure what the surrounds are made of, but I'd think hard before putting something on them.
Click to expand...
They do seem to be rare. I saw an old listing on i believe US audio mart. The seller stated that there were only 300 pair made for export under the Mitsubishi name , the same model Diatones were Japan only. I have not been able to verify this so do not take that as gospel . He also states the surrounds are deer hide , that seems a little far fetched to me but who knows. There are a pair on that auction site from Japan , he is asking crazy money w/ free shipping but they would be very expensive to ship.
I was buying a Mitsubishi DA-A15dc amp and the seller tells me he has some speakers to go with it. Amp / pre / speakers all for the advertised price of the amp , I am thrilled to say the least.
 
You must log in or register to reply here.
Back
Top Bottom