John Darko recent 2.1 reviews
Discussion
I’m a fan of JD. Yes he gets his hands on some tasty stuff, but listens to normal music. My type of music. Underworld. Depeche Mode. Etc.
Iv just watched his second video on 2.1 setups. Which is what I have-
Sonos Connect, optical out
Audiolab 6000a
Monitor Audio RX1
BK XLS200 DF via speaker level Neutrik
It sound brilliant. Almost full range, fast with no bloat or boom.
But JD’s recent discussions with using DSP / HPF on the stereo speakers has got me thinking. I have misplaced the port bungs, but would using a pair of bungs essentially have the same effect as DSP? Or am I thinking about this in a far too simplistic way?
Iv just watched his second video on 2.1 setups. Which is what I have-
Sonos Connect, optical out
Audiolab 6000a
Monitor Audio RX1
BK XLS200 DF via speaker level Neutrik
It sound brilliant. Almost full range, fast with no bloat or boom.
But JD’s recent discussions with using DSP / HPF on the stereo speakers has got me thinking. I have misplaced the port bungs, but would using a pair of bungs essentially have the same effect as DSP? Or am I thinking about this in a far too simplistic way?
Too many videos on the Darko YT feed. Do you have a direct link to it?
Re: bungs - Yes, too simplistic.
Bungs are good for taming the overall bass response. Think of it in terms of the bass and treble controls as an analogy. The bass control reduces a group of frequencies. DSP though is more selective; sort of like a graphic EQ. It's more specific.
Using the bung is helpful where the speaker position is too close to a side- or a back-wall. Speakers get a 3dB sonic boost from each adjacent flat surface, and we hear this mostly in the bass region. The back wall = +3dB, the floor = +3dB, the side wall = +3dB. These are all based on a woofer being 1ft from each surface. Typically then, a pair of RX1 on stands tall enough to get the tweeters to ear height will have the woofer more than a foot from the floor, so the bass boost for that surface will be less, and more importantly already accounted for in the design. Put the same speaker on the floor though and it will change things.
Stick an RX1 in a corner though and the bass will increase by rear wall + side wall reinforcement, so +6dB. You'd hear that most at the port frequency but also in the rest of the bass and midrange area. Using the port bung will mute the port frequency, and that's an important first step for many people who have the speakers in a difficult position. The higher acoustic bass frequencies will still be affected though since they're derived from the bass driver rather than the bass port. The answer there is to change the speaker position.
To put dB in to some kind of context, 6dB would be measurable as a doubling of a specific frequency's sound pressure level. We don't perceive sound the same way though. For us to hear what we think of as double, it would need a 10dB increase. That doesn't mean you can ignore a 6dB increase, or any increase come to that. You'll hear the effect and, perhaps more importantly, it will increase the energy in the room that excites room modes. These are the constructive and destructive interference points that make bass peaks and bass nulls in a room.
A DSP tries to correct some of that. It will never overcome bass nulls. This is where the speaker and listener position interacts with the effects of the room dimensions in the way sound bounces between opposite walls. Where there's a null - a cancellation point - then it's an energy black hole. The only fix is to change the speaker position.
Peaks are easier to attenuate by producing very narrow focus adjustment to take away some of the energy.
There are different qualities of DSP too. Basic systems can be quite crude and use only one seating position, and leave a noticeable sonic fingerprint on the sound. They'll often ignore bass and sub-bass as it's difficult to deal with. Better systems will EQ for bass and measure a half-dozen or more seating points to get a better acoustic map of the room.
Re: bungs - Yes, too simplistic.
Bungs are good for taming the overall bass response. Think of it in terms of the bass and treble controls as an analogy. The bass control reduces a group of frequencies. DSP though is more selective; sort of like a graphic EQ. It's more specific.
Using the bung is helpful where the speaker position is too close to a side- or a back-wall. Speakers get a 3dB sonic boost from each adjacent flat surface, and we hear this mostly in the bass region. The back wall = +3dB, the floor = +3dB, the side wall = +3dB. These are all based on a woofer being 1ft from each surface. Typically then, a pair of RX1 on stands tall enough to get the tweeters to ear height will have the woofer more than a foot from the floor, so the bass boost for that surface will be less, and more importantly already accounted for in the design. Put the same speaker on the floor though and it will change things.
Stick an RX1 in a corner though and the bass will increase by rear wall + side wall reinforcement, so +6dB. You'd hear that most at the port frequency but also in the rest of the bass and midrange area. Using the port bung will mute the port frequency, and that's an important first step for many people who have the speakers in a difficult position. The higher acoustic bass frequencies will still be affected though since they're derived from the bass driver rather than the bass port. The answer there is to change the speaker position.
To put dB in to some kind of context, 6dB would be measurable as a doubling of a specific frequency's sound pressure level. We don't perceive sound the same way though. For us to hear what we think of as double, it would need a 10dB increase. That doesn't mean you can ignore a 6dB increase, or any increase come to that. You'll hear the effect and, perhaps more importantly, it will increase the energy in the room that excites room modes. These are the constructive and destructive interference points that make bass peaks and bass nulls in a room.
A DSP tries to correct some of that. It will never overcome bass nulls. This is where the speaker and listener position interacts with the effects of the room dimensions in the way sound bounces between opposite walls. Where there's a null - a cancellation point - then it's an energy black hole. The only fix is to change the speaker position.
Peaks are easier to attenuate by producing very narrow focus adjustment to take away some of the energy.
There are different qualities of DSP too. Basic systems can be quite crude and use only one seating position, and leave a noticeable sonic fingerprint on the sound. They'll often ignore bass and sub-bass as it's difficult to deal with. Better systems will EQ for bass and measure a half-dozen or more seating points to get a better acoustic map of the room.
Edited by Lucid_AV on Saturday 3rd July 13:47
This was the first Kef KS50 wireless speakers with new sub. If I remember it’s late into the vid where he mentions the DSP.
https://youtu.be/Y2Lc8oOinOY
This was the latest. Hedd Audio active set up.
https://youtu.be/_X16-VfQ7wI
https://youtu.be/Y2Lc8oOinOY
This was the latest. Hedd Audio active set up.
https://youtu.be/_X16-VfQ7wI
In his recent video on the Powernode/KEF LS50Meta/KEF KC62 sub he discussed the high pass filtering available on the Powernode - essentially the DSP is only sending the lowest signal that the speakers can manage, 50hz in this case, and sending below that to the subwoofer (I believe the LS Metas are capable of 45hz but seeing as he's pally with the chief KEF engineer, Jack O-B, who told him to set it at 50hz)
The reason for doing so is to stop the speakers working to their lower limits and letting the sub deal with that and thus the Metas play cleaner with less distortion as he found out with those three bits of kit when he said "I've hit paydirt here!" but you'd hope so for £4k.
AV receivers have been doing this for years, but it's not a room correction system as it's just directing parts of the signal to the speakers best suited for it. Speaker bungs are to tone down the bass if it's too much for a room due to placement but it could help better integrate your speakers and sub? And some speakers come with a full bung and a half bung so that's an option - costs hee-haw to mess around with so it's worth a bash to see if you prefer it or not?
The reason for doing so is to stop the speakers working to their lower limits and letting the sub deal with that and thus the Metas play cleaner with less distortion as he found out with those three bits of kit when he said "I've hit paydirt here!" but you'd hope so for £4k.
AV receivers have been doing this for years, but it's not a room correction system as it's just directing parts of the signal to the speakers best suited for it. Speaker bungs are to tone down the bass if it's too much for a room due to placement but it could help better integrate your speakers and sub? And some speakers come with a full bung and a half bung so that's an option - costs hee-haw to mess around with so it's worth a bash to see if you prefer it or not?
Gassing Station | Home Cinema & Hi-Fi | Top of Page | What's New | My Stuff