Driver longevity

BrannigansLaw

There are a bunch of Peerless CSX woofers available locally at a nice price. I'm looking at these and thinking, these CSX 10" drivers are cheaper and probably very competitive with say, the lower end plastic frame SB series, or the Dayton  Designer series.. But I hesitate knowing that these must be 20+ year old drivers. How much life can be left in them? 

I have limited experience with this. I have some 90s vintage commercial speakers using SEAS poly cone rubber surround midwoofers.  The rubber has become... 'dried out' for lack of a better word - lost it's suppleness and feels more like unheated heat-shrink tubing than supple rubber. I don't have original specs for the woofers so can't say how much this has shifted the TS parameters. On the other hand, I have my ACI spirits which were built some 25 years ago, and the vifa p21 woofers in those seem to be holding up fairly well. And I see a thriving trade in some vintage JBL and KEF woofers that must be even older.

Is this a concern for you with your older drivers? Do other soft parts or even the motor degrade with age somehow? Where do you draw the line on older drivers? How old is too old for you?

ani_101

the two things i am aware of is surround rot if it is untreated foam - the CSX 10 are not, so that's fine. The next thing is cone / suspension sag.... the only remedy for that is to store the drivers upside down for a few months and hope they spring back. usually there will be a little sag and not too drastic, so if you are using drivers of the same age / sag then it should be fine, but mixing very old drivers and new ones, there will be change in T/S due to the sag between the new/old ones.

Having said that take a look at JR's thread where he talks about the Scan Speak 10" which were NOS at PE. If you don't mind, where are you located and what CSX drivers are available and pricing for them? 

jr@mac

The CSX cone trumps the SB and Dayton offerings you mentioned. If the surround is supple and there is no sag, you simply cannot go wrong with them - especially if pricing is as good as you are implying. No idea why Peerless/Vifa/Tymphany/whoever stopped using that material. 

As far as I know, some of the CSX drivers used the motor that eventually found its way into the HDS series. The HDS uses a better frame (except for the stupid truncated aspect) - but there were sandwich cone drivers commonly referred to as Poor Mans HDS etc. That could be hearsay and rose colored glasses too, for all I know. 

dcibel

My first DIY speaker was a CSX, great drivers and the best looking poly cone IMO.

As for age, rubber surround ages as well just not in the same way that foam does. It will stiffen over time, especially if exposed to sunlight. If the drivers have been kept in the dark the rubbe condition should be okay, but as always measuring TS and designing from there is always preferred over datasheet info.  I have old 830884 Peerless drivers that I still listen to and are doing just fine.

PWRRYD

I bought a pair of Vifa PJ17*** (don't remember their exact p/n) back around 1992 from Madisound.  They were extremely nice die cast fame 6.5", mineral filled poly cone, soft dust cap, rubber surround drivers.  I used them briefly in my car system back then, then stored them in the closet for 20 years.  They were stored sitting verically so there wasn't any cone sag.  After I found PETT and got into DIY speaker building I pulled them out hoping for a great pair of midbasses.  Their surrounds and everything else looked and felt prestine.  But when I measured them with my WT3 the Fs and Qes were more than double the manufacturer's spec.  So much so that they modeled useless as midbasses.  Did the magnets lose that much strength sitting so long?  Why else would Qes go up so much? I flogged them pretty good with extended sine waves to loosen up the suspension.

dcibel

For comparison sake, some years back I bought an OLD pair of ATC 12" woofers, they had seen plenty of use and the surround was crispy. Here's what the Q parameters looked like on that:

* Q(ms)= 8.649
* Q(es)= 0.603
* Q(ts)= 0.563

I had the surrounds replaced with new, and you could easily feel the different moving the cone with you hand. The resulting Q parameters were more in line with what I was expecting.

* Q(ms)= 4.139
* Q(es)= 0.400
* Q(ts)= 0.364

That's the different between old and crusty vs new and loosey-goosey. These have a fabric "m roll" surround.

BrannigansLaw

Great discussion here guys, and thanks for all the feedback. In truth this was not something I gave a lot of thought to until I ran into the few vintage speakers I mentioned. I don't know how they were stored or used as I 'inherited' them, but my own speakers seem to hold up fine so maybe I'm worrying needlessly.

The seller says the surrounds are in great shape and the drivers have been in use daily, boxes are now being parted out. I've dealt with him before and he is a stand up guy and has lots of DIY experience, really knows his stuff. Being that the price is great, these are hard to come by, and the Rival aluminum woofers haven't worked out, I'm inclined to grab them... open to being talked out of it though, I've got lots of drivers on the shelf already, not least 4 SLS-8 and 2 SLS-12  

Ani, these are in Canada and I don't think the seller is looking to ship outside of Canada. Given the current border situation I think it may be more hassle than it's worth for you yanks... That being said, it sounds like there's interest here for the extra drivers (he has 8)? I'm not sure I'll need more than 2-4, and the least I could do is make any I don't use available for trade/sale at the price I got them here before anywhere else. If I get all 8, they will work out to ~25 USD each. He also has a pair of TB W8-2145 fullranges available for $175 CAD/125 USD, and a pair of sonanace sonamps. I have no use for either of those, but if I get the woofers could probably grab them for someone here. You can see all the ads here:

https://www.canuckaudiomart.com/userads.php?user_id=5109

ani_101

Yes, you are absolutely right. The last drivers I recently got from Giwa took about a month just sitting to clear customs. Shipping from Canada always takes longer, but now it's even more uncertain. 


Though the 10" CSX looks like a real good value, even if shipping to US is going to double it....

6thplanet

What would you estimate it would cost to get the TB's to 47150?

BrannigansLaw

6thplanet said:

What would you estimate it would cost to get the TB's to 47150?

Looks like it works out to about $50. I assume made in China which means duty, and the drivers are heavy. May be possible to get it done cheaper using a reshipper like Crossborderpickups, this is just the postal service calculator. 

To be honest, I was imagining more that whenever it's possible for us to have meetups again, whether a big one like Indiyana or something smaller and less formal, I'd drive down with the drivers and whoever was interested could meet up and do some listening, trading, or just shoot the breeze a bit. I realize that's an uncertain prospect at this point though

ani_101

That would be great. Where are you located, and did yo u come down for Indiyana or Grand Rapids meetup? 

That would really be the ideal situation, if everything goes fine in the fall...!

Wolf

He was at the last GR.

6thplanet

Ehh, yeah $50 a bit steep. That puts them $25 away from brand new. Honestly I'm thinking about the Indy meet. If that's on your radar, I'd be interested in the TB's

BrannigansLaw

ani_101 said:

That would be great. Where are you located, and did yo u come down for Indiyana or Grand Rapids meetup? 

That would really be the ideal situation, if everything goes fine in the fall...!

I was Ani, at the meniscus GR meetup last fall. Bald beardy white guy from Canada. I heard your design but didn't get the pleasure of meeting you or many others, this was my first event like this. 

6thplanet said:

Ehh, yeah $50 a bit steep. That puts them $25 away from brand new. Honestly I'm thinking about the Indy meet. If that's on your radar, I'd be interested in the TB's

I had planned to make either Indiyana (more likely) or meniscus again this fall. That is of course, pending what goes on with covid in the meantime; right now I don't think I'm even allowed to cross the border for recreational purposes, and frankly not sure I'd be in a hurry if I could.

I do plan on it though; with a little luck, I may even finish a project by then! Would be a nice change from starting them and moving to a new one halfway through;) 

Wolf

The Meniscus/CSS shindig was set aside to allow InDIYana to be in September this year. 

BrannigansLaw

Wolf said:

The Meniscus/CSS shindig was set aside to allow InDIYana to be in September this year. 

Well that certainly simplifies matters, InDIYana it will be!

BrannigansLaw

FYI pulled the trigger on these... if my fried hypex fa123 gets repaired in time, I may cook up an OB project with them in keeping with the inDIYana theme. Maybe 2 x CSX woofers a side,  CSS wr125 for mids, and the Linaeum dipole up top? Could be a fun first dipole/OB build

Wolf

You might want to read the rules. I see some NLA drivers listed there. Nothing saying you can't build with them and bring them in the spirit of, but they might be exempt from the theme.

BrannigansLaw

Wolf said:

You might want to read the rules. I see some NLA drivers listed there. Nothing saying you can't build with them and bring them in the spirit of, but they might be exempt from the theme.

Yeah I figured that. I didn't mean for the contest, just in keeping with the general theme. No problem if I can't compete. If that's discouraged I'll rethink the idea.

ani_101

No, you are encouraged to get anything and play it.... 
Just that it won't be part of the contest as it falls outside of the parameters. On the flip side you get play your own track on it outside the contest...

Kornbread

The frequency response of the Linaeum tweeter was often faulted for a large drop in the top octaves but I found when taking measurements from various angles, the highs were present, just not straight on.  I still wonder about digging those out of the stack-o-stuff and mounting them at an angle so straight on is good and the null resides more to the sides.  For what it's worth, I like them.      

kenrhodes

KB, aiming the null at the wall might be a good way to control some of the room reflections while keeping the on-axis in the sweet spot. 

BrannigansLaw

Kornbread said:

The frequency response of the Linaeum tweeter was often faulted for a large drop in the top octaves but I found when taking measurements from various angles, the highs were present, just not straight on.  I still wonder about digging those out of the stack-o-stuff and mounting them at an angle so straight on is good and the null resides more to the sides.  For what it's worth, I like them.      

I have found the same thing - experimented with them as-designed, and mounted at a 90deg angle. To be honest I couldn't decide which I liked better, but this was nearfield and just quick and dirty measure/adjust with the minidsp.

I also like them! The character of the highs was quite nice and I preferred them by quite a margin over the Hivi TN28 and the Dayton ND20 I was trying at the same time. This was an experiment in adding a top-mount tweeter to a set of CSS FR125 computer speakers I built. They definitely weren't the last word in detail, but the sense of space they projected, for lack of a better word, was rather addictive. 

Kornbread

Wonder what their 360* radiation pattern looks like.  Small but deep null front/back and a broad null to both sides?  Yeah, not the most detailed for sure but unoffensive and if memory serves correctly, delicate sounding.  In general, I'm a fan of the odd stuff so ...