How to upgrade Velodyne 12" sub amp?

roymail · « **on:** 16 Oct 2007, 11:28 pm »

My Velodyne 1200R is part of my modest home theater. When playing DVD's with relatively low hz. material at realistic levels, it "clips" pretty often. The internal amp is just running out of power during those "peaks." Good examples are Disney movies like Ice Age, Toy Story, Madagascar, Happy Feet, etc. Of course, explosions on action flicks just give it fits. I want to pull the plate amp and replace it with one that can handle whatever. Anyone have suggestions? I don't have an unlimited budget, so lets keep it real. Thanks.

slbenz · « **Reply #1 on:** 17 Oct 2007, 01:12 am »

Quote from: roymail on 16 Oct 2007, 11:28 pm

My Velodyne 1200R is part of my modest home theater. When playing DVD's with relatively low hz. material at realistic levels, it "clips" pretty often. The internal amp is just running out of power during those "peaks." Good examples are Disney movies like Ice Age, Toy Story, Madagascar, Happy Feet, etc. Of course, explosions on action flicks just give it fits. I want to pull the plate amp and replace it with one that can handle whatever. Anyone have suggestions? I don't have an unlimited budget, so lets keep it real. Thanks.

When my Velodyne HGS-12 stopped working, Velodyne installed a new amp to replace the one that stopped working for only a couple of hundred dollars. You may want to contact Velodyne to see if the current DD series Class D amps work in your sub. You must be playing your sub quite loud since it is rated for 1000 watts with 2000 watt peaks or the volume level is set quite high. My HGS is rated for 1250 watts with peaks of 3000 watts so hopefully that will be enough. It can rock my whole house!! Your problem sounds exactly what I experienced with the Velodyne HGS-10. It was too small a driver for my room (14'w x20'd x12'h) even though it has the same power amp as my HGS-12. Hope Velodyne can find a solution for you.

roymail · « **Reply #2 on:** 17 Oct 2007, 04:46 pm »

slbenz, I'll email Velodyne and see what they suggest. Otherwise, I figure there must be plenty of folks on AC that have experience with various plate amps who can offer suggestions. Come on guys... jump in here!

roymail · « **Reply #3 on:** 17 Oct 2007, 05:02 pm »

slbenz, I read your post again and now realize that you must be referring to the newer model, Velodyne SPL-1200R, with the 1000 watt amp. I wish that was my sub but its not. Mine is one of the older, original 1200R subs. I don't recall the specs on the amp but I doubt it's more than 100 watts. My sub is at least 8 years old although it has not seen excessive use over time. And, by the way, on those movies I mentioned, it doesn't take very high volume to cause clipping. I don't think this sub was designed to handle today's demanding HT needs. My room size is similar to yours. Just wanted to clear things up a bit.

Bob Reynolds · « **Reply #4 on:** 17 Oct 2007, 05:07 pm »

roy, how do you know the sub's amp is clipping?

If it really is, do you have the sub's level matched with the main speakers? Maybe the level is just too high so you've lost headroom.

Is the sub in a corner, if not placing it there will give you a free boost (up to 9dB; 3dB for each boundary) and then turn the sub's level down.

Mike B. · « **Reply #5 on:** 17 Oct 2007, 05:27 pm »

I am wondering if this is a acoustic feedback problem? I have older Velodyne 12 subs and really need to keep them turned down to not over power the sound.

roymail · « **Reply #6 on:** 17 Oct 2007, 06:47 pm »

Bob, it only happens on very low material, but when it does, the sound is scary bad and sounds partly mechanical and electrical. It's sort of like the speaker is hitting the magnet or something. I may not have my audio terminology correct so help me out if I'm wrong. I would appreciate any constructive advice. The sub is located sort of in the middle of the wall since no corner is available in this room. So I don't get the bass boost you're speaking of.

Mike, I can turn it down but it still happens, just not as loudly. I don't know how playing with the crossover would change much. Any ideas? Thanks, guys.

mcullinan · « **Reply #7 on:** 17 Oct 2007, 06:54 pm »

I know you can call the support department at Velodyne and if they dont suport the sub anymore, they will give you a price to upgrade it to a new version.
Mike

roymail · « **Reply #8 on:** 17 Oct 2007, 08:55 pm »

I placed a call to Velodyne customer service and tried two different extensions. They must be pretty busy since I never did get to talk with anyone. I ended up leaving a message for a call back. I'll report back.

Does anyone have suggestions about adjusting the sub to limit the problem with clipping I described above? Thanks.

-- Roy

randytsuch · « **Reply #9 on:** 17 Oct 2007, 09:11 pm »

Quote from: roymail on 17 Oct 2007, 06:47 pm

Bob, it only happens on very low material, but when it does, the sound is scary bad and sounds partly mechanical and electrical. It's sort of like the speaker is hitting the magnet or something. I may not have my audio terminology correct so help me out if I'm wrong. I would appreciate any constructive advice. The sub is located sort of in the middle of the wall since no corner is available in this room. So I don't get the bass boost you're speaking of.

Mike, I can turn it down but it still happens, just not as loudly. I don't know how playing with the crossover would change much. Any ideas? Thanks, guys.

That sounds more like you are bottoming out the driver than amp clipping to me. If you drive the sub hard enough to exceed the driver's excursion, it will cause a metal to metal sound. I have never done it with my sub, but have seen other people describe it. It is very bad for your driver, and will end up breaking it eventually.

I am surprised you can do it that easily. Maybe something is wrong with your driver?

BTW, I recently "upgraded" my old energy sub. I bought an apex senior sub amp from apex-jr. I would not fit in the sub, so I made a "frame" for it out of 1x4's, and have it sitting next to my sub. The sub is hidden, behind the couch, so appearance does not matter. Only problem is that it is more succeptible to hum now.

But, this is only temporary, I am almost done building a rythmik sub.

Randy

roymail · « **Reply #10 on:** 17 Oct 2007, 09:55 pm »

Randy, I've read about the Rythmik amps and sub kits. I'd be very anxious to know how that works out for you. Which one are you building? Are you going to use the Servo controlled amp w/Linkwitz board?

OK, I just got off the phone with Rob at Velodyne. He was very familiar with my sub... so much so that the first thing he told me was that I was calling it the wrong model. It's a "Foundation Series" sub... a F1200. Sorry guys, my bad! It's a good sub for most music but not for today's HT. He said they were great for Dolby Pro-logic in the day before DD/DTS came along. Now the low frequency demands of HT require far more power storage and larger caps for those peaks. For that reason all their designs have changed over time. Many now are either ported with larger amps (DLS 5000R) or they have very powerful internal amps linked through their patented servo designed woofers.

He said that most likely the amp's power caps were being drained which was causing "clipping" instead of the driver bottoming out due to over excursion. He also said that just replacing the amp wouldn't get the job done, and that another plate amp wouldn't interface with their servo-controlled driver. Bummer!

So, for now I'll just have to turn it down. I could replace both the amp and the driver...

Any thoughts?

slbenz · « **Reply #11 on:** 17 Oct 2007, 09:58 pm »

Quote from: roymail on 17 Oct 2007, 05:02 pm

slbenz, I read your post again and now realize that you must be referring to the newer model, Velodyne SPL-1200R, with the 1000 watt amp. I wish that was my sub but its not. Mine is one of the older, original 1200R subs. I don't recall the specs on the amp but I doubt it's more than 100 watts. My sub is at least 8 years old although it has not seen excessive use over time. And, by the way, on those movies I mentioned, it doesn't take very high volume to cause clipping. I don't think this sub was designed to handle today's demanding HT needs. My room size is similar to yours. Just wanted to clear things up a bit.

Roymail,

Sorry for the confusion. Checked the Velodyne site and believe you own the F-1200R which you are correct is a 100 watt powered sub. Your suspicions were correct about your sub bottoming out. I found this article that mentions your sub is good for music but marginal for home theater: http://www.10audio.com/perf_sub.htm

As for plate amps, you may want to check into Hypex. They carry a line of plate amps specific for subs. Here is a link to a source:http://www.bmm-electronics.com/brands.asp?ID1=1&ID2=57

It could be less expensive and hassle-free to go with a newer sub that can handle today's home theater environment. My concern with your current sub is that it was not designed for a more powerful sub amp and damage could result using the 400 watt Hypex plate amp. Outlaw Audio sells a sub for about the same price as the top-end Hypex plate amp. The Outlaw LFM-1 Compact has a Class D amp rated for 250 watts with peaks of 1000 watts. But if you could extend your finances more, I would go with the LFM-1 Plus. It sports a 12" driver. And according to the Velodyne subwoofer selector, you will need the newer SPL-1500R which at AudioAdvisor is selling for $999.

I feel your pain. I used to own a Velodyne VA1012 rated at 65 watts using Klipsch Heresy II mains and KG2 for surround when home theater was starting. That Velodyne did the same thing you describe. Adjusting level controls didn't solve the problem. Once I replaced that sub with my current HGS-12, problem solved. Even the Velodyne HGS-10 I tried couldn't keep up because the driver was too small even though it uses the same amp as my HGS-12. With rooms our size, you will probably need a 12" driver with adequate power to drive it. But at least if you do try an Outlaw sub, you have 30 days to return it for your money back. Just giving you information to think about. Best of luck with your quest to correct this issue with your sub.

Slbenz

roymail · « **Reply #12 on:** 17 Oct 2007, 10:09 pm »

slbenz, you're right about the model of my sub being F1200. Read my post above your last.

Thanks for all the good information. I think that until I figure out what my next move will be, I'll put my Yamaha prologic receiver into the system. At least that will eliminate much of the problem if I don't turn it up too high. Several years ago I blew another sub on U-571 using DTS. Those depth charges are killers!

I appreciate the advice. I'll be looking at all options at this point. Thanks again for your help, guys.

-- Roy

warnerwh · « **Reply #13 on:** 17 Oct 2007, 10:17 pm »

If you can build a box then you'll get much more sub for the money going DIY. There's plenty of help for design etc.

roymail · « **Reply #14 on:** 17 Oct 2007, 10:30 pm »

So what is the general concensus for HT only... sealed or ported enclosure? Thanks!

Bob Reynolds · « **Reply #15 on:** 17 Oct 2007, 11:37 pm »

Quote from: roymail on 17 Oct 2007, 06:47 pm

Bob, it only happens on very low material, but when it does, the sound is scary bad and sounds partly mechanical and electrical. It's sort of like the speaker is hitting the magnet or something. I may not have my audio terminology correct so help me out if I'm wrong. I would appreciate any constructive advice. The sub is located sort of in the middle of the wall since no corner is available in this room. So I don't get the bass boost you're speaking of.

Mike, I can turn it down but it still happens, just not as loudly. I don't know how playing with the crossover would change much. Any ideas? Thanks, guys.

Roy, I don't think what you are describing is the amp clipping. It sounds like to me the driver is bottoming out -- being driven beyond its range. I've heard it before on my Spendor S8e during Lord of The Rings I -- scared the crap out of me. That prompted the purchase of my sub.

You will get some boundary boost - from the floor and the wall behind the sub, assuming the sub is pretty close to the wall. In a corner you'd get another wall boundary boost. So you're probably doing at best as you can in this regard.

The bottom line is that replacing the sub's amp won't help any. You'd need to either add another sub so you can reduce the level or buy a larger more capable sub.

Some sub's have a filter that attenuates the lower frequencies to avoid this situation -- it's a protection mechanism. The crossover between the mains and the sub won't make any difference.

Bob Reynolds · « **Reply #16 on:** 17 Oct 2007, 11:46 pm »

Roy, when you said you turned it down it still happens only at a lower volume, are turning the sub's level down or the system level down? Turning the sub's level down should avoid the problem.

If you will be considering a new sub, this might interest you: http://www.audioadvisor.com/prodinfo.asp?number=2VESPL1500RB

Looks like a great deal to me.

roymail · « **Reply #17 on:** 18 Oct 2007, 02:04 am »

Bob, I appreciate the advice and insight based on your experience. Also, thanks for the link to the SPL 1500R. No doubt it would be everything I could hope for. I'm not sure I'm ready to drop that kind of cash on a new sub, though... time will tell.

I came home from work and changed the "SW" setting on my processor to rebalance the bass at a lower level. It helped, but of course didn't completely solve the problem. I'll be looking into several options including some DIY stuff. Thanks for all the help.

-- Roy

randytsuch · « **Reply #18 on:** 18 Oct 2007, 03:10 am »

Quote from: roymail on 17 Oct 2007, 09:55 pm

Randy, I've read about the Rythmik amps and sub kits. I'd be very anxious to know how that works out for you. Which one are you building? Are you going to use the Servo controlled amp w/Linkwitz board?

You can read about my project here
http://www.audiocircle.com/index.php?topic=45643.0

I actually need to post some more pics soon, as I have almost finished bracing the cabinet now. Looks ugly inside now, but the walls are definitely stiffer than when I started.

Randy

slbenz · « **Reply #19 on:** 18 Oct 2007, 03:23 pm »

Roymail,

If you are looking to build your own sub, you may want to check out PartsExpress. Here is a link to one of several DIY kits they offer by mail with a 45 day return policy: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-770. Or maybe swap out the 12" driver of your Velodyne with a higher rated driver from PartsExpress and purchase one of their plate amps? Just a thought.

slbenz