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Discussion Starter · #1 ·
It seems my 17 yr. old Velodyne F-1200 sub is dead and can't be repaired. The Velo guy said if the woofer extends to full excursion and makes a loud hum, it's either the woofer or the servo that's cooked. Well, that's exactly what it does, and Velo doesn't have parts to fix it.


So, what to do w/ the nice Velo sealed box and presumably good amp? Seems like I could pop in another cone, hook it up and have sound, albeit not what it was before, but probably better than the two car subs I'm running for the garage stereo.


I looked around the DIY forum and couldn't find anything that would be a primer for a first time DIYer trying to salvage what's left, like me. So, figured I'd start a thread.


What say ye?
 

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Are you wanting to just throw a new driver in your exisiting box? Sure you can do that, but your in the DIY section. So i would say to you look around your room decide the largest enclosure you can fit. Then decide how much $ you want to spend. And we can help you from there. Designing your own sub box and building it really is an easy thing to do and a great way to save alot of money.
 

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Discussion Starter · #3 ·
LOL - maybe I don't get what "DIY" is all about then. Yeah - throw another driver in the box is what I had in mind. But I have no idea at all of how/where to begin even looking for what I'd need - or exactly what I *would* need to do that... Is it as simple as pull the old driver out of the box, unhook the + and - leads and plug in a new driver, or would there be more to it?


Sorry if I posted this in the wrong place. TIA for any help/advice tho!
Oh - and cheap is the operative here, relatively speaking. But a driver would be pretty inexpensive, I'm assuming? Like under $100?? ??? (I have no idea, really - just guessing.)



As far as replacing the dead Velo, I'm not looking to DIY there. Trying to decide whether or not to bite on a "trade in" offer that Velodyne made me. A guy over on the Subwoofer forum suggested a Rythmik sub, but for less than the Rythmik, I can get a Velo Optimum 12. But it's hard to decide having never heard either!
 

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I have an older velodyne servo sub myself (Model "Servo 1200"). One issue that I've thought of is will the servo amplifier work without the servo feedback? Would it function as a regular amplifier? If not, the amp wouldn't be usable for anything other than a replacement sub driver. Technically, the servo feedback is used to compare to the original signal and adjust the amplified signal to match the best, helping to reduce distortion. If there is no servo feedback, I wonder what the amp would to to compensate... Maybe I'll try unplugging the servo feedback wire on mine and see if it still functions.
 

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If the cone goes to full excursion and STAYS there, it's not the driver or the servo, it's the amplifier.
 

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It is unlikely the servo-feedback amplifier will work correctly without servo-feedback. If it is a repairable assembly, then it could be modified by a knowledgeable person. I expect you are left with an enclosure, and no driver or amp. You will have to modify the enclosure to accept a new driver and amplifier if you don't want to scrap the whole thing. It may be easier to start over, if you want to explore DIY. Otherwise, you may sell what is left for parts, or take the trade-in offer.
 

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Quote:
Originally Posted by CottyGee /forum/post/18154268


Geeeze, really? I would have sworn that's not what the guy from Velodyne told me.

Yes, servo or not, when an amp pegs the speaker, and there's mains hum coming from the speaker, along with a burning smell, the output stage of the amplifier is shorted, putting straight DC voltage through your speaker and cooking it. The mains hum appears because under the immense load of the shorted transistors, the power supply's regulation cannot cope and it lets AC ripple get through.
 

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You should disconnect the speaker from the amp and test them separately. If the amp has burned out the driver, there's only the box left to salvage. If the driver has survived, it could be paired with another amp. Unfortunately, without the servo the driver probably doesn't work well in that box. I would expect the resonance frequency to be too high, with a high Q as well.
 

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if it's indeed shot, DIY and don't look back
 
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