You can't fix room nodes with dsp.
If you sit in a null in your example you would need to add 30dB of boost at the required frequency but a few feet in either direction you probably had a peak which is now another 30dB higher.
Besides 30dB boost would probably fry either speakers or amps.
Search for bass traps, either here or on the web in general.
Furnishing can make a surprisingly large difference.
A large, cloth-upholstered sofa or chair makes a great bass trap, an Eames chair makes more problems! ;-)
If you sit in a null in your example you would need to add 30dB of boost at the required frequency but a few feet in either direction you probably had a peak which is now another 30dB higher.
Besides 30dB boost would probably fry either speakers or amps.
Search for bass traps, either here or on the web in general.
Furnishing can make a surprisingly large difference.
A large, cloth-upholstered sofa or chair makes a great bass trap, an Eames chair makes more problems! ;-)
So no, if he used the miniDSP 2-way amp, the active crossover would function as LP, and HP and even EQ if it was used (I think the mid does)
And room modes....
With bass traps you CAN fix a lot more than without using EQ. The physics are beyond me (especially right now) but if you can drain the energy even a little, it seems EQ's can in fact fix time domain issues!
But again, the key is the traps.
Best,
E
And room modes....
With bass traps you CAN fix a lot more than without using EQ. The physics are beyond me (especially right now) but if you can drain the energy even a little, it seems EQ's can in fact fix time domain issues!
But again, the key is the traps.
Best,
E
The most promising system I've seen were active bass traps to which another member here linked once (should have kept the link).
The idea was that if you have a couple of 15s pumping out the tunes at one end of the room there would be another, identical pair at the far end playing the same signal inverted and delayed according to the room dimension. Bass reflections and therefor room nodes almost completely disappeared.
Expensive though...
The idea was that if you have a couple of 15s pumping out the tunes at one end of the room there would be another, identical pair at the far end playing the same signal inverted and delayed according to the room dimension. Bass reflections and therefor room nodes almost completely disappeared.
Expensive though...
Yeah, Ethan is one of the good guys in audio.
The system I'm on about is described here provided the link works:
http://vbn.aau.dk/files/12831869/AC-phd.pdf
The system I'm on about is described here provided the link works:
http://vbn.aau.dk/files/12831869/AC-phd.pdf
Charles, thanks for the info. I figured the dsp won't be able to take care of the big problems. That phd paper is a bit overwhelming for me although the concept is amazing.
I've been toying with the idea of bass traps for quite some time and was thinking of using a hemp based product instead of mineral wool. Cutting the material, building a frame and wrap it in fabric is not my issue since I'm a fairly crafty person. I don't have much technical knowledge so measurements and calculations for this application are an unknown territory. That's why I was hoping I could cut corners using dsp. I guess I was wrong.
The material I found had a density of 42 kg/m3 max thickness being 22cm. It is being sold like a mattress.
This is how my response looks like right now:
I've been toying with the idea of bass traps for quite some time and was thinking of using a hemp based product instead of mineral wool. Cutting the material, building a frame and wrap it in fabric is not my issue since I'm a fairly crafty person. I don't have much technical knowledge so measurements and calculations for this application are an unknown territory. That's why I was hoping I could cut corners using dsp. I guess I was wrong.
The material I found had a density of 42 kg/m3 max thickness being 22cm. It is being sold like a mattress.
This is how my response looks like right now:
Attachments
Seems to me while financially intensive it is technically quite elegant a solution if it works as prescribed.
Anything room acoustics I'd have to read up on myself so sadly you are pretty much on your own there. So far I have been lucky due to my preference of cosy spaces with carpets, rugs, curtains etc. and nowadays bass traps would be vetoed by the wife anyways. ;-)
However gearslutz.com has a 'Studio building & Acoustics' section. It may well be worthwhile to search there.
https://www.gearslutz.com/board/studio-building-acoustics/
Anything room acoustics I'd have to read up on myself so sadly you are pretty much on your own there. So far I have been lucky due to my preference of cosy spaces with carpets, rugs, curtains etc. and nowadays bass traps would be vetoed by the wife anyways. ;-)
However gearslutz.com has a 'Studio building & Acoustics' section. It may well be worthwhile to search there.
https://www.gearslutz.com/board/studio-building-acoustics/
I was looking at that thread the other day. I have some work to do haha.
Apparently it will be a while till I get the capacitors and resistors.
Any suggestions on what do to about the woofers? Leave them alone? Or power them separately? If yes, what xover solution to go for? I curently use a 2x20w el34 amp and the one not in use is a 2x30w kt88.
Apparently it will be a while till I get the capacitors and resistors.
Any suggestions on what do to about the woofers? Leave them alone? Or power them separately? If yes, what xover solution to go for? I curently use a 2x20w el34 amp and the one not in use is a 2x30w kt88.
You should experience the improvements that you'd read about using active xo, and just start with actively crossing over the woofer. It's the series inductor that ruins control of the woofer, so start there. Leave all else passive, and hear what happens. You could try right now disconnecting the woofer and playing just the tweeter-mid combo to get an idea of how happy the amp will be without pushing the woofer/inductor without spending anything.
Costs money or DIY effort to come up with the low pass xo, but there are adjustable off the shelf xo for under $100. And you don't have to measure anything -- just add bass to taste!
Costs money or DIY effort to come up with the low pass xo, but there are adjustable off the shelf xo for under $100. And you don't have to measure anything -- just add bass to taste!
Last edited:
I almost got convinced by the other member to leave the woofer alone
Could you give me some examples of said xos?
There's a Rolls SX45 at P-E that would work, as it's 12dB/oct
But the dilemma is that if it's for the bass only, then any old thing incl car audio active xo stuff, would be acceptable. But if you later also want to go active xo for the top end, you'd want something better sounding, and then something like MiniDSP would be a better value.
And then there's the DIY route, and there are pcbs for you to roll your own active xo...
But the dilemma is that if it's for the bass only, then any old thing incl car audio active xo stuff, would be acceptable. But if you later also want to go active xo for the top end, you'd want something better sounding, and then something like MiniDSP would be a better value.
And then there's the DIY route, and there are pcbs for you to roll your own active xo...
That's not really true, as components don't need to be tied over a board
And removing the coil, you eliminate its effect of added resistance which sums
to driver's Re and has been taken into account by the designers ( Qt is the sum of Qe and Qm ).
I think that most people rave about driving the woofer directly from the (pre-filtered) amp because of the slightly major volume that they hear
And removing the coil, you eliminate its effect of added resistance which sums
to driver's Re and has been taken into account by the designers ( Qt is the sum of Qe and Qm ).
I think that most people rave about driving the woofer directly from the (pre-filtered) amp because of the slightly major volume that they hear
This is true. It will lower the Q of the LF roll-off. The effect may or may not result in an improvement.
There are non benfits of going active beside having a new toy that can be reprogrammed on a constant basis more easily plus one has to have far greater imagination to tune the speaker passively for you have at least 2 big issues to solve, FR and impedance, and the latter better be benign enough which is not that easy to accomplish. EricS knows how Focal was designing near "dead short" impedance spots for no particularly obvious reason.
Sincerely yours, 99% twin brother.
Inductor values ct800
Good morning all. I’m a new member, and a new owner of a “ basket case” pair of Canton ct1000s. I am building the crossovers since they were missing, and the only information l lack is the value of the inductors. The ct 800 and the ct1000 use a very similar crossover, with identical components. If anyone could provide those inductor values, I’d be eternally grateful! Thanks!
Good morning all. I’m a new member, and a new owner of a “ basket case” pair of Canton ct1000s. I am building the crossovers since they were missing, and the only information l lack is the value of the inductors. The ct 800 and the ct1000 use a very similar crossover, with identical components. If anyone could provide those inductor values, I’d be eternally grateful! Thanks!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.