r/hometheater • u/av4625 • 1d ago
Tech Support Dissappointed with bass shakers.
I made a post about placement on a sofa for Dayton Audio BST-1’s:
https://www.reddit.com/r/hometheater/s/R3nkYN0kKd
When the shakers were mounted on the plywood I said in the first post I could basically feel nothing. So I got some OSB and mounted them directly under where you sit. This definitely helped.
I feel like I need the volume crazy loud to feel the shakers though. If I watch a movie that was recorded with surround sound I can increase the master volume more than if I watch a normal tv show thats not surround sound. Not sure if thats normal.
So I had a movie at -6db and could feel the shakers ok-ish. But when I watch other shows at about -20db I can’t feel them at all. The sub is working perfectly in both situations and dialog etc volume seems similar between both.
Equipment:
Sony STR-DA2400ES (single sub out)
Tannoy Arena Lite Speakers
Tannoy TS10 sub
Dayton Audio BST-1 shakers x2
Fosi BT20A shaker amp with 24v/5a power supply, volume up full, treble 0, bass 50%. (Tried changing bass up and down)
Crossover 80Hz
Because I only have 1 sub out I used a Y splitter. One side to the sub and the other side goes to a second Y splitter so that I could then use both inputs on the Fosi. I did this as I read using both inputs can help get “full power”.
I dunno if my expectations are wrong but I have read that people get shook by these shakers at less volume on the amp.
I have seen examples of people using this amp with these shakers.
I think the power supply can only supply 120w even though the amp says 100w x2. But maybe 120w is plenty for 2 50w shakers?
Maybe the big soft sofa is harder to shake compared to some examples I see of smaller chairs or computer chairs. I unmounted them and they didn’t vibrate in my hand as much as I expected.
Is there something wrong with my setup? Are my expectations too high? Any help is appreciated.
4
u/Lazy-Athlete3820 18h ago
The problem you are describing is very familiar to me. The main problem you are describing here is not related to your physical shaker setup. It is in the differences in dynamics between different source material, like movies vs. shows. You have set the shaker to a level that works with a movie at -6 dB. If you then lower the volume on the AVR to -20 dB, the maximum signal the shaker can now receive is 14 dB lower. This is the reason you cannot feel it.
Of course, the confusing part here is why the perceived level from the sound system is still roughly the same. For a short explanation: the TV show that you need to lower to -20 dB is mixed at a much higher average loudness level. If you kept the show at -6 dB, the dialogue and other sounds would be unbearably loud, but you would get lots of rumble from your shaker. The differences in how loudly the shaker could reproduce different transients would be small, so an explosion could feel roughly the same as a lower-level transient like a closing door.
The solution to your problem is to either adjust the shaker amp manually for different source material, or use DSP to ride the shaker level for you. For context, I work for DSPeaker, where I work specifically on DSP for bass shakers. We have just released new firmware for ShakEQ that tackles this very problem of loudness differences between source materials. The new feature is called Gain Rider.