Refoaming Woofers (Snell Type E Series II)

[Old-Timer]

I have a pair of Snell Type E Series II speakers that I've owned since the late 1980's. I owned about a dozen pair of other brands prior to these.

The main selling point was their sound - I've never wanted to look for anything else once I purchased these. A secondary factor was the fact that each speaker assembly is hand-tuned to within 0.5 db of a reference speaker assembly.

Unfortunately, they have succumbed to surround foam rot. So I seek input from the forum members and hope that you will answer some questions for me?

1.) Snell recommends against refoaming the woofers. They say that it will not return them to the original performance and will disturb the hand-tuning that was performed at the factory. Their suggestion: buy new replacement woofers (which will include new inductors to modify the crossover so it will match the reference speaker once again) from them. The cost: $186.00 per woofer. Has anyone had experience refoaming the woofers (or having them refoamed)? How was the sound, compared to when they were original?

2.) I'm skeptical that merely replacing the surrounds (provided that they are the correct type and are installed properly) would affect the speaker's response that greatly. Does anyone have any input on this?

3.) Another option (instead of refoaming) would be to replace the woofers with non-Snell replacement drivers. Would it be possible to install after-market woofers and restore the sound to the original? How do I determine suitable replacements? How would I choose which replacement to purchase and install?

I retired early due to health issues and do not have a large budget with which to work. I would like to spend as little as would be required, but without compromising their sound.
Any suggestions or input will be greatly appreciated.

 

[Verdinut]

I have a pair of Snell Type E Series II speakers that I've owned since the late 1980's. I owned about a dozen pair of other brands prior to these.
Unfortunately, they have succumbed to surround foam rot. So I seek input from the forum members and hope that you will answer some questions for me?

1.) Snell recommends against refoaming the woofers. They say that it will not return them to the original performance and will disturb the hand-tuning that was performed at the factory. Their suggestion: buy new replacement woofers (which will include new inductors to modify the crossover so it will match the reference speaker once again) from them. The cost: $186.00 per woofer. Has anyone had experience refoaming the woofers (or having them refoamed)? How was the sound, compared to when they were original?

Any suggestions or input will be greatly appreciated.

The situation is that identical foam characteristics are probably no longer available. That means you would not be to obtain as good a performance with a different kind of foam composition.

As I understand, the cheapest and most practical solution would be, as Snell suggested, to replace the woofers with Snell's replacement woofers and inductors.

 

[Russdawg1]

How much does it cost to refoam them?

My guess, less than $20 a driver.

Refoam them, see how the sound. If they aren’t “perfect” then you are only $40 in and can get the new woofers from them.

If they sound good, then you’ve saved upwards of $200.

You’d be surprised how much something that is supposed to be a “huge difference” actually affects the sound.

My guess, most couldn’t tell the refoam from the original.

 

[TLS Guy]

If the new foam has a different compliance to the old foam, then yes, it will affect the sound. It will significantly change the T/S parameters of the driver. No, you can not change drivers and return the speakers to original performance, not remotely close.

I would do as Snell recommends. You seem to kike those speakers and want to keep them as you have enjoyed them. The cost is very small compared to the cost now of speakers of that quality.

 

[TLS Guy]

I note that those speakers measured very well. Very good bass extension. The frequency response is very smooth with a slight"'BBC Smiley" dip response around 3 KHz. This is far preferable to the all too common rise at that frequency. That fault tends to give speakers a very smooth presentation and a sense of acoustic depth. That was common at that time as the BBC thought that was a more optimal response curve. For near filed listening like the BBC had to do in their outside broadcast trucks I actually believe they were correct.

It seems you would have to spend big dollars now to match them. I would say you would be well advised to preserve them as close to original condition. If you don't then I think you will pine for them.

 

[highfigh]

I have a pair of Snell Type E Series II speakers that I've owned since the late 1980's. I owned about a dozen pair of other brands prior to these.

The main selling point was their sound - I've never wanted to look for anything else once I purchased these. A secondary factor was the fact that each speaker assembly is hand-tuned to within 0.5 db of a reference speaker assembly.

Unfortunately, they have succumbed to surround foam rot. So I seek input from the forum members and hope that you will answer some questions for me?

1.) Snell recommends against refoaming the woofers. They say that it will not return them to the original performance and will disturb the hand-tuning that was performed at the factory. Their suggestion: buy new replacement woofers (which will include new inductors to modify the crossover so it will match the reference speaker once again) from them. The cost: $186.00 per woofer. Has anyone had experience refoaming the woofers (or having them refoamed)? How was the sound, compared to when they were original?

2.) I'm skeptical that merely replacing the surrounds (provided that they are the correct type and are installed properly) would affect the speaker's response that greatly. Does anyone have any input on this?

3.) Another option (instead of refoaming) would be to replace the woofers with non-Snell replacement drivers. Would it be possible to install after-market woofers and restore the sound to the original? How do I determine suitable replacements? How would I choose which replacement to purchase and install?

I retired early due to health issues and do not have a large budget with which to work. I would like to spend as little as would be required, but without compromising their sound.
Any suggestions or input will be greatly appreciated.

What is on the label that's attached to the woofer? If it's a similar driver to the ones in the Snell speakers that were re-painted for one of my customers, it's Peerless. If that's the case, I would contact Tymphany to give them the part number and have them tell you if they still make a driver that matches the specs (parameters).

 

[TLS Guy]

I have done some research on this.

Most of your speakers had the Vifa M21WN-09/08. Now that woofer was 4 ohm, even though the speaker is rated at 4 ohm. Some of those speakers I understand had the SEAS H334 also NLA. In any event Snell modified those VIFA speakers with beads of special dope on the surrounds. This was to push the break up made up another 1000Hz or so to raise the crossover frequency. So it is not nonsense that the speaker replacements have to come form Snell. If you use a stock surround you will not have a good speaker.

The Snell replacement is the Vifa P21WO-20 . I think they also modify that surround. Now this driver is 8 ohm and that is the reason why the crossover has to be modified. This woofer has recently been discontinued and the dealers are out. When those replacement drivers run out at Snell, I suspect that will be the end of the line for those speakers.

I don't see any reports of the sound after this repair. If you like those speakers this is your best option. However I should caution you the speakers may not sound like they did.

So I think there is some risk with this woofer replacement. If you are risk adverse then it is time for you to go speaker shopping.

I should state for those of you who think that a change in the surround could not have a drastic effect on a speaker, then think again. I learnt in my youth working on the JW module, that reflection back from the edge of the cone has a huge effect on the speaker response. So preventing them does extend the useful bandwidth of a speaker. Treating the surround is actually a good way of reducing or eliminating these reflections.

 

[TLS Guy]

How much does it cost to refoam them?

My guess, less than $20 a driver.

Refoam them, see how the sound. If they aren’t “perfect” then you are only $40 in and can get the new woofers from them.

If they sound good, then you’ve saved upwards of $200.

You’d be surprised how much something that is supposed to be a “huge difference” actually affects the sound.

My guess, most couldn’t tell the refoam from the original.

Wrong advice!

 

[Old-Timer]

I have done some research on this.

Most of your speakers had the Vifa M21WN-09/08. Now that woofer was 4 ohm, even though the speaker is rated at 4 ohm. Some of those speakers I understand had the SEAS H334 also NLA. In any event Snell modified those VIFA speakers with beads of special dope on the surrounds. This was to push the break up made up another 1000Hz or so to raise the crossover frequency. So it is not nonsense that the speaker replacements have to come form Snell. If you use a stock surround you will not have a good speaker.

The Snell replacement is the Vifa P21WO-20 . I think they also modify that surround. Now this driver is 8 ohm and that is the reason why the crossover has to be modified. This woofer has recently been discontinued and the dealers are out. When those replacement drivers run out at Snell, I suspect that will be the end of the line for those speakers.

I don't see any reports of the sound after this repair. If you like those speakers this is your best option. However I should caution you the speakers may not sound like they did.

So I think there is some risk with this woofer replacement. If you are risk adverse then it is time for you to go speaker shopping.

I should state for those of you who think that a change in the surround could not have a drastic effect on a speaker, then think again. I learnt in my youth working on the JW module, that reflection back from the edge of the cone has a huge effect on the speaker response. So preventing them does extend the useful bandwidth of a speaker. Treating the surround is actually a good way of reducing or eliminating these reflections.

I definitely want to restore the original sound of my Snell's. Some people complain that they are lacking in bass response. My experience is that, if the recording contains bass, it is reproduced. If it doesn't, it won't be. It's not boomy, and that's what I love about them. It is the most neutral speaker I've ever listened to.

If money were not an issue, I would purchase the replacement woofers from Snell, without a doubt. However, I retired early due to health issues; and my problem is that, after paying all of my essential monthly expenses, I have only $65 left over for non-essential purchases.

I'm hoping to hear from someone who has actually gone the refoam route and to see what their experience has been.

I found an online vendor of surrounds who asked me what woofer my speakers used, Vifa or Peerless. I pulled the woofer and found that it is an SEAS. He claims that he has the appropriate surrounds. Since he told me that I would need specific surrounds (i.e., Vifa or Peerless), and since he admitted to forgetting about the SEAS but that he did know of them, I am inclined to take him at his word.

I also have found that the "successor" to Snell (Audio Note in the UK) makes speakers based upon the Snell E's design. Its model AN-E runs from a low of $8,600 per pair to more than $100,000. An incentive to repair my Snell's to original condition.

For now (unless someone else provides additional input),I think I will try replacing the surrounds. But I will begin looking for part-time work that will provide the funds needed to purchase the Snell replacement woofers.

 

[Old-Timer]

The situation is that identical foam characteristics are probably no longer available. That means you would not be to obtain as good a performance with a different kind of foam composition.

As I understand, the cheapest and most practical solution would be, as Snell suggested, to replace the woofers with Snell's replacement woofers and inductors.

I definitely want to restore the original sound of my Snell's. If money were not an issue, I would purchase the replacement woofers from Snell, without a doubt. However, I retired early due to health issues; and my problem is that, after paying all of my essential monthly expenses, I have only $65 left over for non-essential purchases.

I'm hoping to hear from someone who has actually gone the refoam route and to see what their experience has been.

I found an online vendor of surrounds who asked me what woofer my speakers used, Vifa or Peerless. I pulled the woofer and found that it is an SEAS. He claims that he has the appropriate surrounds. Since he told me that I would need specific surrounds (i.e., Vifa or Peerless), and since he admitted to forgetting about the SEAS but that he did know of them, I am inclined to take him at his word.

For now (unless someone else provides additional input), I think I will try replacing the surrounds. But I will begin looking for part-time work that will provide the funds needed to purchase the Snell replacement woofers.

 

[Pogre]

Oh boy, I looked your speakers up and it looks like you have some very nice speakers! Listen to @TLS Guy, he is very knowledgeable on these things and appreciates speakers like yours. He won't take shortcuts or steer you wrong.

Good luck with those speakers!

 

[TLS Guy]

I definitely want to restore the original sound of my Snell's. If money were not an issue, I would purchase the replacement woofers from Snell, without a doubt. However, I retired early due to health issues; and my problem is that, after paying all of my essential monthly expenses, I have only $65 left over for non-essential purchases.

I'm hoping to hear from someone who has actually gone the refoam route and to see what their experience has been.

I found an online vendor of surrounds who asked me what woofer my speakers used, Vifa or Peerless. I pulled the woofer and found that it is an SEAS. He claims that he has the appropriate surrounds. Since he told me that I would need specific surrounds (i.e., Vifa or Peerless),and since he admitted to forgetting about the SEAS but that he did know of them, I am inclined to take him at his word.

For now (unless someone else provides additional input),I think I will try replacing the surrounds. But I will begin looking for part-time work that will provide the funds needed to purchase the Snell replacement woofers.

Well, that is interesting. You have a set with the less common SEAS H334 woofers. There are significant differences between that and the Vifa woofer.

Re about the same on all 4 tests @ about 3 ohms
Fs on the Seas was 30, on the Vifa, 25 hz
Qes 0.39 on the Seas and 0.33 on the Vifa
Qms 2.9 on the Seas and 2.10 on the Vifa
Qts 0.345 on the Seas and 0.29 on the Vifa
Le about the same on all 4 at 0.39 mH
Zmax 25 ohm on the Seas and 22 ohms on the Vifa
Vas 85L on the Seas and 120 on the Vifa
Bl about the same on all 4 at 5.5
Kms 750 n/M on the Seas and 530 on the Vifa
Mms about the same on all 4 at 21 grams
Sens. about the same on all 4 at 89 dB@1W/1M

Now I suspect that the boxes are tuned differently.

The Snell replacement has these parameters.

Now I have found out that others have reported success with a Silver Flute woofer as a replacement for the SEAS.

T/S parameters of Silver Flute replacement.

Re 3.7 Ohms
Sensitivity 93.7 dB
Power 100 watts
Fs 31.0 Hz
Qms 1.51
Qes 0.27
Qts 0.23
Vas 72.3 Ltrs
Mms 23.7 g
Cms 1111.3 mM/N
Sd 0.0214 M2
BL 7.9 TM
X-max 5 mm
Le @ 1kHz 0.52 mH

Krm 1.324 mW
Kxm 17.644 mH
Erm 0.819
Exm 0.596

Full details of the
Silver Flute W20RC38-04 8" Woofer Wool Cone 4 ohm

Note that the above woofer is 4 ohm, so the crossover will not need changing. Of great importance is that the VAS of this and SEAS are virtually identical. This parameter has the biggest influence on box volume.

The Qts of this driver is a little lower. Now the sensitivity of the SEAS is quoted at 1 watt/ 1 meter. I would bet that the sensitivity of the Silver flute is at 2.83 volts 1 meter, as that is the way sensitivity is quoted now. That being the case the sensitivities are virtually identical.

The bottom line is that I think the Silver Flute woofer is a better replacement for your SEAS driver than the Snell Vifa replacement, which would be better if you had the Vifa driver.

My best advice is to purchase a couple of those Silver Flute drivers. They are $38.2 a piece which I think is at your budget and comparable to the refoaming costs.
Also these woofers have a rubber surround, so you should not be bothered with rotted foam down the road.

 

[shadyJ]

Well, that is interesting. You have a set with the less common SEAS H334 woofers. There are significant differences between that and the Vifa woofer.

Re about the same on all 4 tests @ about 3 ohms
Fs on the Seas was 30, on the Vifa, 25 hz
Qes 0.39 on the Seas and 0.33 on the Vifa
Qms 2.9 on the Seas and 2.10 on the Vifa
Qts 0.345 on the Seas and 0.29 on the Vifa
Le about the same on all 4 at 0.39 mH
Zmax 25 ohm on the Seas and 22 ohms on the Vifa
Vas 85L on the Seas and 120 on the Vifa
Bl about the same on all 4 at 5.5
Kms 750 n/M on the Seas and 530 on the Vifa
Mms about the same on all 4 at 21 grams
Sens. about the same on all 4 at 89 dB@1W/1M

Now I suspect that the boxes are tuned differently.

The Snell replacement has these parameters.

Now I have found out that others have reported success with a Silver Flute woofer as a replacement for the SEAS.

T/S parameters of Silver Flute replacement.

Re 3.7 Ohms
Sensitivity 93.7 dB
Power 100 watts
Fs 31.0 Hz
Qms 1.51
Qes 0.27
Qts 0.23
Vas 72.3 Ltrs
Mms 23.7 g
Cms 1111.3 mM/N
Sd 0.0214 M2
BL 7.9 TM
X-max 5 mm
Le @ 1kHz 0.52 mH

Krm 1.324 mW
Kxm 17.644 mH
Erm 0.819
Exm 0.596

Full details of the
Silver Flute W20RC38-04 8" Woofer Wool Cone 4 ohm

Note that the above woofer is 4 ohm, so the crossover will not need changing. Of great importance is that the VAS of this and SEAS are virtually identical. This parameter has the biggest influence on box volume.

The Qts of this driver is a little lower. Now the sensitivity of the SEAS is quoted at 1 watt/ 1 meter. I would bet that the sensitivity of the Silver flute is at 2.83 volts 1 meter, as that is the way sensitivity is quoted now. That being the case the sensitivities are virtually identical.

The bottom line is that I think the Silver Flute woofer is a better replacement for your SEAS driver than the Snell Vifa replacement, which would be better if you had the Vifa driver.

My best advice is to purchase a couple of those Silver Flute drivers. They are $38.2 a piece which I think is at your budget and comparable to the refoaming costs.
Also these woofers have a rubber surround, so you should not be bothered with rotted foam down the road.

Very nice advice, Mark. The OP is very lucky to have your help!

 

[Old-Timer]

Well, that is interesting. You have a set with the less common SEAS H334 woofers. There are significant differences between that and the Vifa woofer.

Re about the same on all 4 tests @ about 3 ohms
Fs on the Seas was 30, on the Vifa, 25 hz
Qes 0.39 on the Seas and 0.33 on the Vifa
Qms 2.9 on the Seas and 2.10 on the Vifa
Qts 0.345 on the Seas and 0.29 on the Vifa
Le about the same on all 4 at 0.39 mH
Zmax 25 ohm on the Seas and 22 ohms on the Vifa
Vas 85L on the Seas and 120 on the Vifa
Bl about the same on all 4 at 5.5
Kms 750 n/M on the Seas and 530 on the Vifa
Mms about the same on all 4 at 21 grams
Sens. about the same on all 4 at 89 dB@1W/1M

Now I suspect that the boxes are tuned differently.

The Snell replacement has these parameters.

Now I have found out that others have reported success with a Silver Flute woofer as a replacement for the SEAS.

T/S parameters of Silver Flute replacement.

Re 3.7 Ohms
Sensitivity 93.7 dB
Power 100 watts
Fs 31.0 Hz
Qms 1.51
Qes 0.27
Qts 0.23
Vas 72.3 Ltrs
Mms 23.7 g
Cms 1111.3 mM/N
Sd 0.0214 M2
BL 7.9 TM
X-max 5 mm
Le @ 1kHz 0.52 mH

Krm 1.324 mW
Kxm 17.644 mH
Erm 0.819
Exm 0.596

Full details of the
Silver Flute W20RC38-04 8" Woofer Wool Cone 4 ohm

Note that the above woofer is 4 ohm, so the crossover will not need changing. Of great importance is that the VAS of this and SEAS are virtually identical. This parameter has the biggest influence on box volume.

The Qts of this driver is a little lower. Now the sensitivity of the SEAS is quoted at 1 watt/ 1 meter. I would bet that the sensitivity of the Silver flute is at 2.83 volts 1 meter, as that is the way sensitivity is quoted now. That being the case the sensitivities are virtually identical.

The bottom line is that I think the Silver Flute woofer is a better replacement for your SEAS driver than the Snell Vifa replacement, which would be better if you had the Vifa driver.

My best advice is to purchase a couple of those Silver Flute drivers. They are $38.2 a piece which I think is at your budget and comparable to the refoaming costs.
Also these woofers have a rubber surround, so you should not be bothered with rotted foam down the road.

Thank you!

I had actually come across the possibility of using the Silver Flute in a different forum, but it's low price caused me some concern.

But your comment (and the comment that follows by Shady J) make me very comfortable about using them as replacements.

I entered the world of hi-fi as a teen in the mid-1970's. At that time, I used to read voraciously. However, by the late 1980's, and after several upgrades along the way, I had settled on my system and stopped reading. It wasn't until my surrounds vaporized that I needed to gather more info.

I am now very excited about replacing my woofers, and recovering the sound that I fell in love with.

Again, thanks to all for the various replies. They are greatly appreciated.

 

[Old-Timer]

Oh boy, I looked your speakers up and it looks like you have some very nice speakers! Listen to @TLS Guy, he is very knowledgeable on these things and appreciates speakers like yours. He won't take shortcuts or steer you wrong.

Good luck with those speakers!

Before the surround rot, they were the best sounding speakers I had ever heard. I picked them up in the mid-1980's for under $900 for the pair.

There is a post from TLS Guy after your post that finalized my decision.

I will post back after I have acquired the Silver Flutes and let you all know how it works out.

 

[Old-Timer]

I just ordered the Silver Flute woofers.

As soon as I receive and install them, I will let you know how it turned out.

 

[TLS Guy]

I just ordered the Silver Flute woofers.

As soon as I receive and install them, I will let you know how it turned out.

I was wondering what the outcome of this was. Do you have a means of getting any measurements? An impedance curve would be particularly nice as that would check that these drivers are reasonably tuned to the box.

 

[Pogre]

I will post back after I have acquired the Silver Flutes and let you all know how it works out.

And you did! We appreciate that and get our little shot of the "feel goods" when something works out for someone!

 

[Old-Timer]

I was wondering what the outcome of this was. Do you have a means of getting any measurements? An impedance curve would be particularly nice as that would check that these drivers are reasonably tuned to the box.

I have no means of measuring them. My decision was based upon a compilation of input from many forums and their users (your post being the clincher for me).

My final decision was between the Silver Flutes and replacements from Snell's successor. Budget was a key factor ($93.00, including shipping, for the pair vs. roughly $375 for a pair of Vifa woofers (and crossover components) from "Snell"). Additionally, I had come across an "after" photo of a Snell E-II that had been retrofitted with what appeared to be a Silver Flute woofer (I believe it was from The Speaker Factory). I reached out to them via email, but never received a reply from them.

If they sound terrible (which I'm thinking that they won't), I can always "upgrade' to the Vifa's when finances allow. I also appreciate that the Silver Flutes use a rubber surround (although I've read that they, too, are subject to dry rot - although much less prone than foam).

SIDE NOTE: My original SEAS woofers are not the SEAS H334's; they are H170's. They are marked on the back: "E II L 29" and "E II R 30", which leads me to believe that the speakers I own were from a very early run of the E-II's.

 

[Old-Timer]

UPDATE: I have run into a couple of snags along the way:
1. The latest Windows update borked my computer. I have spent way too much time recovering it, leading to a lack of time to address my Snells.
2. The Silver Flute replacement woofers have a smaller basket assembly, meaning that my cutouts are too big to accommodate them.

The speaker assembly otherwise looks pretty much the same. After some additional thought and research, I have decided to fabricate an adapter to fill in the open space left by the replacement woofers.

Any thoughts, comments, or suggestions?