Blown driver in EA VL110

[pete.young]

Oh poo. It looks I've managed to blow the main driver in my Euphonic Audio VL-110 - it now makes a farty noise at comparatively low volumes especially at the low end of the frequency spectrum. It's an old cab but I've had it a while and grown quite attached to it and it's very useful for practices.

The driver is an unbranded unit labelled '6 Ohms' - the cab has a crossover , a piezo tweeter and a 5" midrange driver and the overall resistance is labelled as 8 Ohm.

Any ideas whether (a) this is a sub or a full range driver ( what I might use as a suitable replacement?

I've emailed the guys at EA to see what they suggest, but if any of the resident gurus have any suggestions I'm very keen to hear them.

[alexclaber]

Shame on you for abusing such a lovely little cab!

Hopefully EA have some spare drivers otherwise it's an usual driver so not sure what to suggest - it is a true woofer, hence the big heavy dustcap and long travel suspension. I initially thought that maybe a BP102 would work but I think the Fs and sensitivity are too low and Vas is too high. If you can find something with Vas ~ 50 litres, Fs ~ 45Hz, Qts ~ 0.35, sensitivity ~ 92dB and midrange good to about 700Hz it should work.

Alex

[guyl]

[quote name='alexclaber' post='448012' date='Mar 28 2009, 12:28 PM']I initially thought that maybe a BP102 would work but I think the Fs and sensitivity are too low and Vas is too high. If you can find something with Vas ~ 50 litres, Fs ~ 45Hz, Qts ~ 0.35, sensitivity ~ 92dB and midrange good to about 700Hz it should work.[/quote]

Once again Alex baffles us with science - this time in greek!!

Gary at EA is really helpful - I'm sure he will be able to sort this out for you!

[JD1]

Yep - Gary is top notch. Drop him a line.

[pete.young]

Gary helped me out when I had problems with an amp, but the speaker contact on the EA site is a guy called John so I've mailed him.

Alex, many thanks for the reply - it does make some sense to me in that I can find the information on the datasheets, but I'm not sure how to interpret the variation, particularly with Vas - the cabinet is probably a lot less than 50l and there are some drivers in the 25-30l range. What's the significance of Qts?

And by the way - there's no need to chastise me for breaking this cab. I'm gutted. It arose out of a set of circumstances that I really should have prevented - using it for too loud a gig, using a head that had the potential to overpower it, not wearing my earplugs and being deafened by the drummer to the point where I couldn't hear the sound breaking up until it was too late. Inshort, failing to obey Alex's rule. I'll be very upset if I can't get it working again.

Is there any harm in putting a full-range driver in, even if the crossover circuit means that it's not seeing the higher frequencies? The Deltalite II 2510 seems to be closer to your ideal values, although Qts and Fs are a bit higher. Beyma SM 110-N looks good but Vas is a bit high

Disappointed that the Celestion offerings in this space all seem to have a high Vas. I'm tempted to ask if there's going to be a vas difference, but I really should know better:-)

[Bill Fitzmaurice]

[quote name='pete.young' post='448628' date='Mar 29 2009, 08:01 AM']Is there any harm in putting a full-range driver in, even if the crossover circuit means that it's not seeing the higher frequencies?[/quote]
The higher the level of engineering the more critical that the correct driver be used. If this cab is as well engineered as rumor has it a different driver would totally muck up the works.

[JD1]

Bill - Slightly off topic so apologies, but why were the VL's so power hungry? I had a VL110 and 210 and you really needed a big amp to drive them.

[Alien]

[quote name='JD1' post='449191' date='Mar 30 2009, 08:17 AM']Bill - Slightly off topic so apologies, but why were the VL's so power hungry? I had a VL110 and 210 and you really needed a big amp to drive them.[/quote]

Hoffmanns Law says that you can't have a small cab that goes low and is efficient. You can, however, have two of the three, so EA traded efficiency to get small size and deep bass. This needs more power for a given volume, but watts are pretty cheap these days.

A

[JD1]

They were also heavy beasties for their size. I guess as a result of the all the transmission line gubbins. Sounded great though.

[pete.young]

I don't think the VL110 has transmission line gubbins. It seems to have a divider down between the front and back (with a hole for cables ) and a port from the back to the front at the top of the cab. I'll take some pictures of it while it's in bits.

Anyway, I've just had a very nice reply from John D at EA who says that they don't hold replacement drivers for VL110, just a recone kit which i don't think is the problem. The driver was custom made for EA by Eminence. John says I need to find a replacement driver with the following specs:

2.5" dia. voice call with winding length 0.75"
80 oz magnet (presumably this is not necessary for a neo driver)
40 Hz to 2 KHz response
Qt between 0.28 and 0.35

He also said: "The woofer is connected directly to the amp without going through any crossover components. We utilize the mechanical rolloff of the driver in the overall design to maximize efficiency."

I can see why it was a custom driver! There are a couple of B&C drivers which are sort of close but don't match the frequency range. I'll need to do some more research. Any suggestions welcomed.

[alexclaber]

Have a look at the Ciare neo 10"s. Neo magnet will need to be about 7oz I think.

Alex

[Bill Fitzmaurice]

Obviously John is in customer service, not engineering.
[quote]2.5" dia. voice call with winding length 0.75"[/quote]Moot.
[quote]80 oz magnet[/quote]Moot
[quote]40 Hz to 2 KHz response[/quote]Moot
[quote]Qt between 0.28 and 0.35[/quote] Less than precise. What you do need to know is Fs, Vas, Qes and Qms at the very least.

[quote]He also said: "The woofer is connected directly to the amp without going through any crossover components. We utilize the mechanical rolloff of the driver in the overall design to maximize efficiency."[/quote]Definitely customer service; the only reason for so doing is to minimize costs. No engineer would ever try to get away with that statement.

You're best off to do the recone, but if you can't find someone to do it for you the above specs are a necessity to get a suitable matching driver. .

Edited April 1, 2009 by Bill Fitzmaurice

[franzbassist]

[quote name='pete.young' post='451939' date='Apr 1 2009, 09:01 PM']I've just had a very nice reply from John D at EA[/quote]

Not sure how many John Ds there are at EA, but one of them, John Dong, is one of the founders!

[alexclaber]

Yes, I was puzzled by that too. Without Vas you have no idea what the driver will do in such a small cab.

Here's another thought - plead with Andy Lewis @ Acme to sell you one of his custom drivers. He normally only sells them as replacements for blown Acme woofers but I'd expect one of them to work better than any other 10" you can buy in a 3-way bass guitar cab.

Alex

[pete.young]

Thanks guys - I'm clearly in over my head since I didn't realise a recone kit would include a voice coil. I'll see if I can find someone round these parts who can recone a speaker for me. There must be plenty of ex-Celestion employees round these parts, now that the old factory is a housing estate.

[escholl]

[quote name='Bill Fitzmaurice' post='452008' date='Apr 1 2009, 10:32 PM']Definitely customer service; the only reason for so doing is to minimize costs. No engineer would ever try to get away with that statement.[/quote]

Yea, i was thinking the same thing there. Glad it wasn't just me wondering why they gave the voice coil size and magnet weight ^_^

[Bill Fitzmaurice]

[quote name='escholl' post='452885' date='Apr 2 2009, 07:18 PM']Yea, i was thinking the same thing there. Glad it wasn't just me wondering why they gave the voice coil size and magnet weight ^_^[/quote]
That's information one would find in a catalog, which is undoubtably what 'John D.' was reading from, not a driver data sheet. Most companies don't allow customer service reps to give out driver data, lest they buy a replacement from an alternate source and thus lose a sale. You'd think that they wouldn't be so stingy if they don't have a driver to sell.

[alexclaber]

[quote name='pete.young' post='448628' date='Mar 29 2009, 01:01 PM']And by the way - there's no need to chastise me for breaking this cab. I'm gutted. It arose out of a set of circumstances that I really should have prevented - using it for too loud a gig, using a head that had the potential to overpower it, not wearing my earplugs and being deafened by the drummer to the point where I couldn't hear the sound breaking up until it was too late.[/quote]

In your defence it's much harder to spot when a 3-way cab is being overdriven because although the woofer may be sounding dirty you'll still be getting clean midrange from the separate midrange driver. Conversely with a 3-way (or woofer+mid) cab it's much easier to spot when the amp is being overdriven because the midrange driver will make the distortion all the more obvious.

Am wondering if your description of the cab innards does make it a rather short transmission line?

Alex

[guyl]

[quote name='pete.young' post='451939' date='Apr 1 2009, 09:01 PM']I don't think the VL110 has transmission line gubbins. It seems to have a divider down between the front and back (with a hole for cables ) and a port from the back to the front at the top of the cab. I'll take some pictures of it while it's in bits.[/quote]

Did you manage to take pictures? The transmission line was a big selling point for these cabs - it'd be interesting to see if it was just marketing boxxxxks!

[alexclaber]

Thinking further about it, there could easily be one divider you'd be able to see, plus another couple behind that which are hidden, and then the final length that looks like the port. That would have sufficient length to be a useful transmission line.

Alex

[Bill Fitzmaurice]

[quote name='guyl' post='453055' date='Apr 3 2009, 05:29 AM']Did you manage to take pictures? The transmission line was a big selling point for these cabs - it'd be interesting to see if it was just marketing boxxxxks![/quote]
If less than four feet long it's not a transmission line, at least not one useful in the electric bass pass band.

[pete.young]

I beg EA's pardon. It is a transmission line cab - I thought that that started with the CL series. Have to say this looks like a cabinet that was made by a proper furniture-making cabinet maker, built with care, precision and love. Some crappy camera pics:

Here's the front of the cabinet. You can just see a slim port at the top of the cabinet which goes all the way to the back. There's a baffle with a hole in it where the cables go through.





At the back with the control panel taken off, you can see another baffle about 1" from the back of the cab. This is blocked off on one side and there's a gap at the bottom, which presumably goes through to the space between the baffles.





To get any further than this, it'll be necessary to knock the cab to bits. I'm not prepared to destroy such a work of art, even if I can't get a working driver and I have to use it as a plant pot stand :-)


The driver doesn't look as though there's anything wrong with it. There again, they never do!

[Bill Fitzmaurice]

The label on the side of the driver looks like Eminence. The foam roll surround indicates a hi-fi style of woofer, not a typical instrument driver. Very similar to this:
[url="http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-110"]http://www.parts-express.com/pe/showdetl.c...tnumber=295-110[/url]
From the numbers on the tag Eminence should be able to provide specs.

BTW, the holes for the wiring should be sealed airtight. Even holes of that size will seriously detract from low end performance.

Edited April 4, 2009 by Bill Fitzmaurice

[pete.young]

Spot on Bill, EA did say that the driver was made for them by Eminence.

The wiring holes are the only air path from the front of the cabinet through to the middle. It doesn't need one at all?

[Bill Fitzmaurice]

[quote name='pete.young' post='454113' date='Apr 4 2009, 09:26 AM']The wiring holes are the only air path from the front of the cabinet through to the middle.[/quote]I doubt that's the case. Look more closely.