Great!
As well as selecting an appropriate high frequency for the tweeters, keep the volume low and the time short.
It's easy to burn out a tweeter which has little self cooling.
As well as selecting an appropriate high frequency for the tweeters, keep the volume low and the time short.
It's easy to burn out a tweeter which has little self cooling.
Greetings, sorry for silence I've been busy fixing old synths. I have refelted the mid and tweeter drivers. It's my first ever attempt at this and I found it a steep learning curve. If I do it again I think my job will be neater. The caps arrived from Wilmslow audio, (great service thanks) and I will recap the cross overs and reassemble the speakers. Looking forward to listening to these. One quick question, I didn't manage to get the cardboard rings that sat on the original felt off intact, are rplacements available? I feel I wouldn't do too well at cutting new ones out...it's a long time since I watched Blue Peter!
Well done! It would appear you have have performed a sterling piece of surgery in replacing the cloth surrounds.
The cardboard rings are sealing gaskets which, as the name suggests, seal a driver against the wooden baffle to prevent air leakage.
In that case, only the mid drivers would need them as the tweeters fire into thin air. Plus the tweeters look nice without the gaskets.
Since the gaskets of the mid drivers won't be seen, I'm sure you can make a passable job of cutting new ones from the required thickness of cardboard.
Finding ready made replacements of the exact required dimensions may be unlikely, though there are possibilities out there such as in this listing for 3/4/5/6/8" speaker gaskets:
https://www.ebay.co.uk/itm/31254907...nRuZWAyDe3GjcyHZWyMNhk9w==|tkp:Bk9SR6KN7bzEZA
5 inch size:
Outer diameter: 166mm
Inner diameter: 144mm
Width: 11mm
Thickness: 2.8mm
The cardboard rings are sealing gaskets which, as the name suggests, seal a driver against the wooden baffle to prevent air leakage.
In that case, only the mid drivers would need them as the tweeters fire into thin air. Plus the tweeters look nice without the gaskets.
Since the gaskets of the mid drivers won't be seen, I'm sure you can make a passable job of cutting new ones from the required thickness of cardboard.
Finding ready made replacements of the exact required dimensions may be unlikely, though there are possibilities out there such as in this listing for 3/4/5/6/8" speaker gaskets:
https://www.ebay.co.uk/itm/31254907...nRuZWAyDe3GjcyHZWyMNhk9w==|tkp:Bk9SR6KN7bzEZA
5 inch size:
Outer diameter: 166mm
Inner diameter: 144mm
Width: 11mm
Thickness: 2.8mm
Thanks Galu, I'll measure the required gaskets and see what I can come up with. I'm just on with those Sugdens so will post about them when I've made some progress.
BTW, has anybody used ultrasonic cleaning to clean old potentiometers? I have the said cleaner but am slightly worried that it may damage the contact surface. Any thoughts?
BTW, has anybody used ultrasonic cleaning to clean old potentiometers? I have the said cleaner but am slightly worried that it may damage the contact surface. Any thoughts?
I've not tried it, but I read that ultrasonic cleaning is appropriate provided the cleaning solution will not harm the carbon track on the pot.
Isopropyl alcohol (IPA) will flush away contaminants without attacking carbon. However, you would have to tell me if IPA can be used in an ultrasonic cleaner. IPA also has the advantage of evaporating quickly, leaving the pot internals dry.
If the metal wiper of the pot is oxidised you may require the use of a deoxidiser spray such as deoxIT DN5.
CAVEAT: With very old and worn pots it might NOT be advisable to use ultrasonic cleaning as its action may loosen the track material.
Isopropyl alcohol (IPA) will flush away contaminants without attacking carbon. However, you would have to tell me if IPA can be used in an ultrasonic cleaner. IPA also has the advantage of evaporating quickly, leaving the pot internals dry.
If the metal wiper of the pot is oxidised you may require the use of a deoxidiser spray such as deoxIT DN5.
CAVEAT: With very old and worn pots it might NOT be advisable to use ultrasonic cleaning as its action may loosen the track material.
Good morning and greeting from the Yorkshire pennines. I've managed to put some more time into the W3 restoration. I have both crossovers recapped and both speakers reassembled (fig 1). One of the speakers is performing well and I feel the sound is pretty good. One however has problems with the mid driver (fig2). It is distorting and sounds as if the cone is damaged which as far as I can see it isn't What should I do? I considered buying a replacement driver, but I think you all know the issues this may involve.
Another factor I'd like to quiz you all about is the front grill on one of the cabinets. See the picture (fig 3). It has dtached and I'm stumped as to how to strech and reattach it. I tried a hair dryer, which certainly makes the material more plyable but it also is a fine line between causing shrinking! I'd be interested if anyone knows what material this is? It seem sto have a plastic content. I'm guessing there's no stocks of this available anywhere?
Another factor I'd like to quiz you all about is the front grill on one of the cabinets. See the picture (fig 3). It has dtached and I'm stumped as to how to strech and reattach it. I tried a hair dryer, which certainly makes the material more plyable but it also is a fine line between causing shrinking! I'd be interested if anyone knows what material this is? It seem sto have a plastic content. I'm guessing there's no stocks of this available anywhere?
Mid driver: Check the that the flexible braided leads that connect the driver terminals to the voice coil are secure. The voice coil itself may be rubbing in the magnetic gap, possibility due to it being off-centered during the replacement of the surround. There is also the possibility of historical damage to, or simple age deterioration of, the voice coil.
Grill fabric: The fabric that was used by Wharfedale is called Tygan. Its synthetic fibres can be contracted by heat after fitting. This was done by holding a single bar electric fire about 6" away from the material for a period of only 5 or 6 seconds. The Tygan then becomes taught and stays taught.
Tygan cloth is still available, here in black:
https://www.thomann.co.uk/adam_hall_0715.htm#:~:text=Speaker Grille Robust nylon, Tygan black, Weight: 330 g/m, Width:
Grill fabric: The fabric that was used by Wharfedale is called Tygan. Its synthetic fibres can be contracted by heat after fitting. This was done by holding a single bar electric fire about 6" away from the material for a period of only 5 or 6 seconds. The Tygan then becomes taught and stays taught.
Tygan cloth is still available, here in black:
https://www.thomann.co.uk/adam_hall_0715.htm#:~:text=Speaker Grille Robust nylon, Tygan black, Weight: 330 g/m, Width:
P.S. Reading through the thread I notice you did not report back that both mid drivers were working OK prior to you refelting them.
Might one of them have been faulty all along?
Might one of them have been faulty all along?
Thanks Galu,
You raised an important question re the mid driver about it's function prior to refelting. I didn't scrutinize the sound very well prior to refelting, but I remember on the whole the speakers were distorting in the mids. so as you suggested the problematic driver may have been shoot from the start. I'll take it out of the cab and see if I can diagonise the problem. I'm hoping I can fix it otherwise I'll have to seek a repacement.
As for the 'cloth' thanks for the link. I investigated the material further and found that Stewmac (picture below) sells material very close to the original material on the W3's so I will invest in some of this.
Again many thanks for your continued help and expertise.
Craig
You raised an important question re the mid driver about it's function prior to refelting. I didn't scrutinize the sound very well prior to refelting, but I remember on the whole the speakers were distorting in the mids. so as you suggested the problematic driver may have been shoot from the start. I'll take it out of the cab and see if I can diagonise the problem. I'm hoping I can fix it otherwise I'll have to seek a repacement.
As for the 'cloth' thanks for the link. I investigated the material further and found that Stewmac (picture below) sells material very close to the original material on the W3's so I will invest in some of this.
Again many thanks for your continued help and expertise.
Craig
Yes, grill cloth for electric guitar speakers. I had actually thought of that. Well found!
Re the faulty midrange driver:
Place your thumbs on opposite sides of the cone and push it in gently and symmetrically. You may hear a rubbing noise as the cone moves in and out, in which case you can be sure the voice coil assembly is fouling the narrow magnetic gap.
As a last resort, carefully slicing off the dust cap just above where it is glued to the the cone would allow you to inspect the suspect area. Below is what you would see in a Super 5 which, remember, is not identical to your W3 midrange and which has had its dust cap totally removed from the cone.
The narrow magnetic gap lies between the inner surface of the brown cylindrical voice coil former and the central metal pole piece.
It is often necessary to insert paper shims (spacers) into the gap to hold the voice coil former in alignment while a cone surround is replaced.
Don't forget to check that the solder joints at each end of the flexible braided lead in wires are secure and not causing an intermittent connection.
In fact, it would be a good idea to connect your multimeter across the driver terminals and check that a constant ohms reading is obtained as you move the cone in and out. Lack of a steady reading would indicate an intermittent connection.
Re the faulty midrange driver:
Place your thumbs on opposite sides of the cone and push it in gently and symmetrically. You may hear a rubbing noise as the cone moves in and out, in which case you can be sure the voice coil assembly is fouling the narrow magnetic gap.
As a last resort, carefully slicing off the dust cap just above where it is glued to the the cone would allow you to inspect the suspect area. Below is what you would see in a Super 5 which, remember, is not identical to your W3 midrange and which has had its dust cap totally removed from the cone.
The narrow magnetic gap lies between the inner surface of the brown cylindrical voice coil former and the central metal pole piece.
It is often necessary to insert paper shims (spacers) into the gap to hold the voice coil former in alignment while a cone surround is replaced.
Don't forget to check that the solder joints at each end of the flexible braided lead in wires are secure and not causing an intermittent connection.
In fact, it would be a good idea to connect your multimeter across the driver terminals and check that a constant ohms reading is obtained as you move the cone in and out. Lack of a steady reading would indicate an intermittent connection.