Your amplifier.
-
WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
ScanSpeak Revelator 13" subs
- Thread starter concorde1
- Start date
So yes, in theory, you can blast all the 200W into the 32W without destroying it even below 10Hz. In practice though, music has a larger crest factor, and you'll probably put a bigger amp on it. And then the risk gets a lot bigger.
Waxx
Major Contributor
But in reality, before you blow the cone of a driver, it will already sound very ugly and you will turn it down lf you want good sound. And xmax is where the driver stops act linear, xmech is where you blow the driver. Xmech is with this driver 28mm (double of xmax) following published specs. That means you need a 1000w at 20Hz freq to get there with this driver, and for longer than a few ms's. And that is THX reference level (105dB) at 20Hz if i simulate it at that power. Normally you will never come near that in reality.
Unless kids or alcohol are involved
Are you a keen woodworker and have you built speakers before...do you know what you're getting yourself in for?
I'm sure there must be some subwoofers available in NZ, maybe just several relatively cheap units dotted around would be 'good enough'.
I'm sure there must be some subwoofers available in NZ, maybe just several relatively cheap units dotted around would be 'good enough'.
Speaker building is good for the soul.
Maybe that explains the state of mine, I obviously need to build more (any).
Last edited:
My youngest built a Mivoc AWX 184 (200 €) into 80 L enclosure CB, driven by Hypex 500 W plate. That gives enough to lift up the roof if driven hard.
As the Mivoc is out of sale, as alternative seems Visaton PAW 46, here for 250€, appropriate.
Scan Speak for mid or high appreciate a lot, but for use in subwoofer overpriced.
As the Mivoc is out of sale, as alternative seems Visaton PAW 46, here for 250€, appropriate.
Scan Speak for mid or high appreciate a lot, but for use in subwoofer overpriced.
Bass distortion is not easy to hear. You may be surprised. Possibly by then other noises (or smells) coming from the thing may indicate imminent doom
There is more than one way to kill a woofer
But yes, these things are quite sturdy and rugged…. I still would not expose one to 1kW
What do you mean by "extreme example?" Thanks!
Good question. I think Villchur had some arbitrary ratio of driver Vas to box volume, but I don't recall. I'm sure some Googling will give you an article. In any event it's more of a marketing than an engineering concept.
Davide
Senior Member
Well ok, this assumes the music has very high infrasonic content (more than the >20hz part you are hearing comfortably, so away from the xmax of the various drivers)
It may also depend on whatever your listing to. If your a LP person and your pre-amp doesn’t filter sufficiently, it may be an extra good idea. We’ve had a topic about this very issue last week. Also, if you apply room EQ, and boost below driver fs, be carefully. Likewise with things like a Linkwitz-transform, especially if the box it smaller than recommended.
My first speakers were AR5s (couldn't afford the AR3s). I'll do some digging for Villchur articles. Once again, thanks!
It was sort of revolutionary back then. Amps had become commonly available with lots of power, and he took advantage of that.
I bought the system in '74 or '75. In addition to the ARs, it included Pioneer separates and a Thorens TD125AB MkII. I had encountered some AR MSTs in a show room in Birmingham, AL during the summer of '74. As an 18 or 19 year old, I was most impressed.
A friend had AR3s. i liked them.
In my shop, I now have a pair of Cerwin-Vega AT15s that are driven by a Harman-Kardon HK670 Twin. The AT15s need new cabinets; I'm hoping that will a winter project for me.
OP
concorde1
Senior Member
- Joined
- Mar 15, 2021
- Messages
- 366
- Likes
- 278
- Thread Starter
- #39
2 newbie things I'm finding confusing:
1. When I view frequency response of 12-15" sub drivers on manufacturers' pages (they usually say it's a sealed or vented box and specify volume), they all drop off sharply at about 50 Hz.
I've looked at this for the ScanSpeak driver, as well as SB Acoustics, B&C, BMS, Beyma, Sica, Dayton.
So to implement these drivers I would have to do massive EQ boosts in the low end? That seems bad.
What I mean is, on a commercial sub, say https://www.audioholics.com/subwoofer-reviews/monolith-13201d-thx-ultra/conclusion , the drop off occurs at a much more impressive ~20 Hz.
2. The ScanSpeak 32W has a resonance frequency of 18Hz. Does that mean I cannot have extension to say 16Hz (pipe organ lowest note), because it requires crossing the 18Hz Fs which will presumably sound unpleasant?
--
I'm not after massive SPL (my room is small-medium at 2200 cubic ft), but I want to have low frequency extension to cover all material in movies (including 10-20 Hz range). I know it's not audible but maybe possible to feel.
My goal is to make something comparable to the Monoprice Monolith 13” THX Ultra or Perlisten D12S.
1. When I view frequency response of 12-15" sub drivers on manufacturers' pages (they usually say it's a sealed or vented box and specify volume), they all drop off sharply at about 50 Hz.
I've looked at this for the ScanSpeak driver, as well as SB Acoustics, B&C, BMS, Beyma, Sica, Dayton.
So to implement these drivers I would have to do massive EQ boosts in the low end? That seems bad.
What I mean is, on a commercial sub, say https://www.audioholics.com/subwoofer-reviews/monolith-13201d-thx-ultra/conclusion , the drop off occurs at a much more impressive ~20 Hz.
2. The ScanSpeak 32W has a resonance frequency of 18Hz. Does that mean I cannot have extension to say 16Hz (pipe organ lowest note), because it requires crossing the 18Hz Fs which will presumably sound unpleasant?
--
I'm not after massive SPL (my room is small-medium at 2200 cubic ft), but I want to have low frequency extension to cover all material in movies (including 10-20 Hz range). I know it's not audible but maybe possible to feel.
My goal is to make something comparable to the Monoprice Monolith 13” THX Ultra or Perlisten D12S.
Those manufacturers' measurements are free air measurements
Which means that if you stand in the middle of a meadow with the speaker in your hands it will measure like that from 1 meter
What matters is the simulated frequency curve that you get when putting the driver in a cabinet (sealed, ported, whatever)
Some people will disagree with this but there is nothing wrong with using a speaker below its Fs point. If you check all my published projects here on ASR you will see that I have always been doing that (even well below the Fs point) and the sound has nothing to complain about (actually very much on the contrary). Of course you need to be careful with the SPL and a high-pass filter can also come in handy (preferably linear phase since that won't impact the phase)
If you want high SPL (like 90+ dB) at around 20Hz I would highly recommend a much bigger cone, in the region of 15-18 inch and in order to increase the cone surface area you can also think about a sealed DOS design (I have published some of those too, really cool stuff in my opinion - when it comes to building a DIY sub that is my recommendation)
