I'd do whatever you want to with them straight off & then it's done & one less thing to worry about.
Plugs = big upgrade generally. Varies between the drivers; actually the FExx6E series benefit more from them, but the FExx7E series also show what I consider to be a substantial improvement. Get the basket & motor damped as well with duct-seal, blu-tak or similar (just make sure you don't impede the airflow). Some people find that grounding (it's not really grounding, more polarising, but you get the idea) the frame to the negative terminal worth doing, at the price of a couple of db sensitivity & a slight alteration in the driver's electrical behaviour as a result.
WRT cone mods, I can't really speak for the 207 as most of my experience with it is with unmodified units a few years back. EnABL is the current flavour / fashion (funnily enough, a mate of mine has just discovered his newly aquired Leak Sandwich speakers have a similar pattern embossed into their (original 1960s) cones, so as per usual, 'what once was old, is again new'
), and there are other things you can do too -for e.g. find the break-up areas & selectively damp.
Plugs = big upgrade generally. Varies between the drivers; actually the FExx6E series benefit more from them, but the FExx7E series also show what I consider to be a substantial improvement. Get the basket & motor damped as well with duct-seal, blu-tak or similar (just make sure you don't impede the airflow). Some people find that grounding (it's not really grounding, more polarising, but you get the idea) the frame to the negative terminal worth doing, at the price of a couple of db sensitivity & a slight alteration in the driver's electrical behaviour as a result.
WRT cone mods, I can't really speak for the 207 as most of my experience with it is with unmodified units a few years back. EnABL is the current flavour / fashion (funnily enough, a mate of mine has just discovered his newly aquired Leak Sandwich speakers have a similar pattern embossed into their (original 1960s) cones, so as per usual, 'what once was old, is again new'
), and there are other things you can do too -for e.g. find the break-up areas & selectively damp.ok for the phase plugs and the basket & motor damping
didnt fully understand the WRT (?) cone mods
the groundig you refer is like this (http://www.humblehomemadehifi.com/Solo206.html) ???
didnt fully understand the WRT (?) cone mods
the groundig you refer is like this (http://www.humblehomemadehifi.com/Solo206.html) ???
Attachments
I'd get at least 100 hours on them on the test bench before anything at all. This weeds out any driver that has a premature failure -- once you start modding any warranty goes out the window.
Phase plugs are a given. People talk about them transforming the whizzer cone drivers.
The shaping of the rear exit when you are basket damping is just as important as the damping itself. The fanatic will use something like Silent Running SR500 to also stiffen the magnet-basket join (as well as shape & damp). SR500 can also be used to stiffen the hollow on the back of the bezel.Ref: Extreme Basket Tricks
Grounding the basket is, i believe, closely related to adding a grounside electron pool. Make sure you have an amp with a ground (ie not a BTL amp). If grounding the basket you are best to run a separate lead to the amp.
As to cone treatment, there are 2 steps. pre-treat (worth doing all by itself) and then EnABL
Pretty much everything is covered in this thread: Coating+phase plugs to FE167. FE207 is actually easier, because it is bigger and it is easier to get at the cramped bits (ie rings under the whizzer).
dave
Phase plugs are a given. People talk about them transforming the whizzer cone drivers.
The shaping of the rear exit when you are basket damping is just as important as the damping itself. The fanatic will use something like Silent Running SR500 to also stiffen the magnet-basket join (as well as shape & damp). SR500 can also be used to stiffen the hollow on the back of the bezel.Ref: Extreme Basket Tricks
Grounding the basket is, i believe, closely related to adding a grounside electron pool. Make sure you have an amp with a ground (ie not a BTL amp). If grounding the basket you are best to run a separate lead to the amp.
As to cone treatment, there are 2 steps. pre-treat (worth doing all by itself) and then EnABL
Pretty much everything is covered in this thread: Coating+phase plugs to FE167. FE207 is actually easier, because it is bigger and it is easier to get at the cramped bits (ie rings under the whizzer).
dave
Attachments
Puzzlekoat pre-treatment:
2 thin coats on the front only, Do the dustcap on FE12x and the topside of the whizzer. The first coat bonds the surface fibres, the 2nd coat sits on top and seals it.
Getting it diluted right is a bit tricky. Since every bottle of modpodge i've had is a bit different in viscosity, and it tends to get more viscous as you work to the bottom of the jar, i don't have a fixed dilution factor.
One fellow commented that it was diluted to about the same viscosity as automatic transmission fluid. It doesn't take much water to dilute it (if you are colouring it use the ink or food colour as a substitute for water) ... i mix small batches (say 1/4" (7mm) or a bit more in the bottom of the 3" diameter jars i use to mix it up), and dilution is measured in drops (5-10).
You want it dilute enuff that it paints on fairly smoothly, but not so dilute that it soaks the cone. You are only trying to bond the fibers near the front surface of the cone. It is also important not to dawdle, as the coating where you start can start getting tacky by the time you get back around to it. (particularily on the bigger cones) If you have coloured the PK you will find that you won't be able to get really even colour. And as the PK gets tacky it becomes even harder (which can be useful to be some interestering varigation effects).
Also note that you are better off with 2 little then too much.
dave
PS: not a good idea to do the back of a FR driver. You want the cone to maintain its flex so that beaming at HF is minimized. Coating both sides creates a constrained layer and increases stiffness much more than the sum of the coating added -- quite usefull on woofers thou.
2 thin coats on the front only, Do the dustcap on FE12x and the topside of the whizzer. The first coat bonds the surface fibres, the 2nd coat sits on top and seals it.
Getting it diluted right is a bit tricky. Since every bottle of modpodge i've had is a bit different in viscosity, and it tends to get more viscous as you work to the bottom of the jar, i don't have a fixed dilution factor.
One fellow commented that it was diluted to about the same viscosity as automatic transmission fluid. It doesn't take much water to dilute it (if you are colouring it use the ink or food colour as a substitute for water) ... i mix small batches (say 1/4" (7mm) or a bit more in the bottom of the 3" diameter jars i use to mix it up), and dilution is measured in drops (5-10).
You want it dilute enuff that it paints on fairly smoothly, but not so dilute that it soaks the cone. You are only trying to bond the fibers near the front surface of the cone. It is also important not to dawdle, as the coating where you start can start getting tacky by the time you get back around to it. (particularily on the bigger cones) If you have coloured the PK you will find that you won't be able to get really even colour. And as the PK gets tacky it becomes even harder (which can be useful to be some interestering varigation effects).
Also note that you are better off with 2 little then too much.
dave
PS: not a good idea to do the back of a FR driver. You want the cone to maintain its flex so that beaming at HF is minimized. Coating both sides creates a constrained layer and increases stiffness much more than the sum of the coating added -- quite usefull on woofers thou.
207E are breaking in
waiting for the phase plugs ...
but I still have to decide the right enclosure (3 options so far: half chang, Martin King MLTL and LT2000 by Bob Brines)
but I've been reading that a tweeter maybe needed (probably the f17), if so what would be the right spot to place them lets say for the Half chang ??
or it doesnt make any difference ??
waiting for the phase plugs ...
but I still have to decide the right enclosure (3 options so far: half chang, Martin King MLTL and LT2000 by Bob Brines)
but I've been reading that a tweeter maybe needed (probably the f17), if so what would be the right spot to place them lets say for the Half chang ??
or it doesnt make any difference ??
Hi
I have build the Fostex 207E boxes as published by Fostex but I need some guidance re damping as none is provided in the published plans. Do I leave the box undamped or should I at least place some foam directly behind the driver whilst leaving unrestricted air flow to the bottom chamber?
Any advice will be welcome
Jozua
I have build the Fostex 207E boxes as published by Fostex but I need some guidance re damping as none is provided in the published plans. Do I leave the box undamped or should I at least place some foam directly behind the driver whilst leaving unrestricted air flow to the bottom chamber?
Any advice will be welcome
Jozua
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