VTF-3 HO "popping"

[dloper]

Hi all.

I purchased a VTF-3 HO in November and was running it with a Harmon Kardon AVR 320. I absolutely love this sub. Music, movies...it is the best. Friends have been blown away by its sound and power. One friend was so impressed he's planning on buying one.

This past week I purchased a Pioneer Elite VSX-84TXSi receiver and had my HT professionally installed. I tweaked the sub gain on the channel level to +10dB, the amp on the sub is set at about 20%.

Last night while playing the opening scene of Star Wars II, when the ships from Naboo(sp???) fly over the sub started popping. This is the scene that I use to show people what this baby can do, and have never heard it do this before. After replaying the scene and removing the cone cover, it is the cone that is popping. The volume on the receiver was set at -9.

Has anyone else experienced something like this?
Or does anyone know what might be causing this popping?

Any help or advice would be greatly appreciated.
Thanks,
David.

[tdekany]

that receiver can calibrate the system. Did you do it (or did the pro company) and then you adjusted it manually? If that is the case your sub is running way too hot. Recalibrate it and go no more than 3db hot. See what happens.

[dloper]

Thanks for your reply.

They calibrated all the speakers, and I boosted the channel gain on the sub. I was playing dvds on a new sony up-converting dvd player via hdmi cable and was not getting the impact that I was before. That is why I increased the gain.

So I switched back to my 5 year old JVC dvd player with audio via optical and the LFE was back where it was. Except for the popping.

I'll try dropping the gain.

Thanks again for your help.

[JHixson]

I would turn the amp on the sub up a little and turn the reciever down. +10 seems a little high, my reciever is at -5 for the sub. How was your HK set?

[AudiblConoiseur]

Dr. Hsu told me to set the receiver to output 0dB to the sub as there is no need to run it hot. Depending on what you read, it may say to set this to more, but he recommends +/-0! Are you sure that you did now blow it somehow or pop it out of its chamber? :eek:

[dloper]

JH:
I think the HK was set at +4. As I said, with the different dvd player, it seemed as if the LFE signal was lost.

AC:
I don't think I did any damage to it. Playing the scene at a slightly lower volume did not result in any popping, but it didn't have quite the impact of that scene either.

Thanks everyone for your help. I'm pretty new to this and need all the help I can get.

[RatFarm]

This is not the only time I have read that someone's HO was 'popping'. I'm beginning to think that maybe the HO driver's excursion capability is not an ideal match to the cabinet volume and amp power. Has anyone noticed this 'popping' with the VTF-3 Mk III ?:confused:

[JonnyOzero3]

+10dB on the Sub level in the AVR might be sending a clipped/oversaturated signal to the sub amp. I'd definitely try reducing it to 0dB, and raising the sub gain on the amp a little to compensate. Do you have a SPL meter? I'd use it to make sure you set things correctly.

[dloper]

Thanks all for your replies.

JO:
No I don't have an SPL meter yet. I do plan on reducing the gain on the receiver when I get home from work.

At what level do you, (or anyone else), have the subs amp set?

Again, thank you all for your input and advice.
I greatly appreciate your help.
David.

[OU812]

Thanks all for your replies.

JO:
No I don't have an SPL meter yet. I do plan on reducing the gain on the receiver when I get home from work.

At what level do you, (or anyone else), have the subs amp set?

Again, thank you all for your input and advice.
I greatly appreciate your help.
David.


Then, adjust the volume/gain on the sub to your liking.

For example, if your receiver's subwoofer level range is -12dB to +12dB, set it "flat" to 0dB. If it is -20dB (low) to 0dB(high), then you would set it flat to -10dB. Be aware the Hsu's amp volume/gain is ultra sensitive, you don't have to turn it up or down that much to make a difference.

The reason you want to set the receiver's sub level flat is to minimize chances the receiver will be sending an already-clipped signal to the sub to get amplified even more. :)

[wid]

When not using a spl meter one normally sets the sub around 10db too hot. Any sub will have a tough time with this kind of setting.




Thanks all for your replies.

JO:
No I don't have an SPL meter yet. I do plan on reducing the gain on the receiver when I get home from work.

At what level do you, (or anyone else), have the subs amp set?

Again, thank you all for your input and advice.
I greatly appreciate your help.
David.

[tdekany]

This is not the only time I have read that someone's HO was 'popping'. I'm beginning to think that maybe the HO driver's excursion capability is not an ideal match to the cabinet volume and amp power. Has anyone noticed this 'popping' with the VTF-3 Mk III ?:confused:

you couldn't be more OFF - Are you trying to say that Dr Hsu doesn't know how to design a subwoofer? :confused: :eek: :eek: :rolleyes:

It is clear that the OP Fd with the settings.

OP - your Pioneer receiver has an auto setup - USE IT.

If you want to up the bass a little, use your remote and adjust it no more than 3db.

I'd bet that sub was running at least 15db hot.
get use to real bass. you will not want to boost it after a week.

As far as the new dvd player, you need to make adjustments to it's settings if the bass isn't as good as with the old player.

[dferrey]

Setting the bass level by ear is asking for trouble. You really need an SPL meter and knowledge regarding how to calibrate your speakers and sub. The numbers on the receiver and sub volume/gain only provide relative volumes and mean nothing as it relates to actual SPLs.

I shudder when I see people asking others what number they set their amp/sub to as the actual levels vary widely based on the specs of the equipment. It's not like a car speedometer where 65 MPH is 65 MPH regardless of the car (within a small tolerance anyway).

[RatFarm]

you couldn't be more OFF - Are you trying to say that Dr Hsu doesn't know how to design a subwoofer? :confused: :eek: :eek: :rolleyes:

No, but the original HO did suffer from similar issues and the driver was revamped. I am only expressing concern because I have an HO/wTurbo on order...:confused:

[craigsub]

No, but the original HO did suffer from similar issues and the driver was revamped. I am only expressing concern because I have an HO/wTurbo on order...:confused:

Rest easy, the driver was not revamped - the original drivers, as delivered by the driver manufacturer, did not match the specs of the original design.

The drivers which are shipping now DO match spec. I have beaten the HO pretty hard, with no problems. Every ported sub seems to have a scene or 2 that causes problems.

[lradden]

No, but the original HO did suffer from similar issues and the driver was revamped. I am only expressing concern because I have an HO/wTurbo on order...:confused: Don't worry the driver in your HO is a completely different driver from head to toe: here's some pics and a comparison of the original HO driver and the new one.http://forum.hsuresearch.com/showthread.php?t=2278&highlight=ho+driver

[RatFarm]

Thanks for the reassurance. I had a bad time with an older M&K sub that kept bottoming so I didn't want to relive those memories. :D

[lradden]

I'd be worried too if I already had a bad experience with a sub like you did. That new HO is one tough mother and really takes a pounding. Oh and it sounds really nice too :)

[cyberbri]

Yes, the settings in the new DVD player need to be set. Dynamic range control could be set to on by default. Perhaps it's outputting a 2-channel signal rather than an actual digital audio stream for DD/DTS. There could be any number of things wrong in the DVD player.

And yes, use the receiver's auto setup. That's what it's there for.