I'd Like To Build a Murphy Corner-Line-Array... BUT...

[Tin_Ears]

Per the title, I want to build Murphy Corner-Line-Arrays but my a door is too close to the wall to build the cabinets as designed. I only have about 3.5" between the wall and the door when it's opened. The cabinets can only be 3.5 inches wide but can be elongated enough to bring the volume up sufficiently. The drivers would still be angled inward at the baffle. In essence, the array would be moved away from the back wall a few inches but otherwise the same... just not a perfect mirror image.

I have two questions:

1. Will the imperfect mirror image affect imaging/phase or frequency response enough to ruin the project?

2. How could I design a center channel that "mostly" matches the L+R? A sealed bi-pole or tri-pole, perhaps? The CC must be movable.

[John L. Murphy]

Re: I'd Like To Build a Murphy Corner-Line-Array... BUT...

I have two questions:

1. Will the imperfect mirror image affect imaging/phase or frequency response enough to ruin the project?

2. How could I design a center channel that "mostly" matches the L+R? A sealed bi-pole or tri-pole, perhaps? The CC must be movable.

Hello Tin_Ears,
The 3.5" limit is a bit of a restriction but you should be able to get around it with a clever shape. I don't think it would mess up the response in any big way. Try to anticipate the listening position and design the enclosure so that you keep the listeners on-axis as much as possible. Don't sweat the enclosure volume too much provided you are going to do custom EQ voicing.

Just to put a bug in your ear...It would be nice if the center channel were also a line array so that with changing listening distance the level of the center channel tracks with the L-R mains. Otherwise, if the center channel is a point source, the sound level will fall off faster than the arrays as you move away from the speakers. If the system is balanced at one listening location then at seats further away the center channel may be too low in level. Now if you happen to be using a large front projector screen that is perforated then you could use a center channel array running from floor to ceiling. Otherwise consider implementing the center channel using horizontal arrays above and below the screen placed where the front wall meets the floor and ceiling. This would require another equalizer to voice the center channel. But the exquisite mid-range clarity of a crossover free full-range center channel speaker may justify the expense and effort.

Cheers!
John

[Tin_Ears]

Re: I'd Like To Build a Murphy Corner-Line-Array... BUT...

Hello Tin_Ears,
The 3.5" limit is a bit of a restriction but you should be able to get around it with a clever shape. I don't think it would mess up the response in any big way. Try to anticipate the listening position and design the enclosure so that you keep the listeners on-axis as much as possible. Don't sweat the enclosure volume too much provided you are going to do custom EQ voicing.

Just to put a bug in your ear...It would be nice if the center channel were also a line array so that with changing listening distance the level of the center channel tracks with the L-R mains. Otherwise, if the center channel is a point source, the sound level will fall off faster than the arrays as you move away from the speakers. If the system is balanced at one listening location then at seats further away the center channel may be too low in level. Now if you happen to be using a large front projector screen that is perforated then you could use a center channel array running from floor to ceiling. Otherwise consider implementing the center channel using horizontal arrays above and below the screen placed where the front wall meets the floor and ceiling. This would require another equalizer to voice the center channel. But the exquisite mid-range clarity of a crossover free full-range center channel speaker may justify the expense and effort.

Cheers!
John

Thank you, John. I've always been impressed with your MCLA. It's excellent news that a slight variation in enclosure shape will have little effect on final sound quality. I'll build them!! The baffle angles will face the primary seating position.

RE CC type: Yes, it will be a line array built as closely like the others as is practicable. I'll be using an acoustically transparent screen though only the CC will be behind it. I know some masking will occur but I'm hoping some additional EQ will mostly mitigate it. All three front channels will be individually EQed via Behringer DEQ2496 units and the spare channel will EQ the subwoofers. The satellites I'm not too concerned about. I asked about making the CC a sealed bi-pole or tri-pole because I know it will image differently than the L/R speakers.