Low Down Sound Cab Club started!

[Chef]

6-800 sounds about right for the 15/6 application.

In the 2x8's that Don has built for me, I do believe the crossover is at about 1.6khz; that's a totally different application tho!

 

[seanm]

That would totally creep me out. Would waste the midrange driver and sound like crap too.

My LDS 1x12 1x6 came with a 1.6kHz crossover, which was the lowest crossover Eminence sold at the time. I actually thought the mid was broken because I heard nothing from it I originally tested it with a CD, so I thought I had broken it moving it to the practice space.

I replaced it with a 800Hz? crossover. There is a thread on it here on TB.

 

[Chef]

I don't know where the crossover is on my 2x12+2x6, but there's a lot of info coming out of those two 6's...

 

[billhilly66]

I asked for 650hz and 4.5khz on my 15/6/1. Don said “no problem”.

 

[RS]

The cabs measure 20"w x 12"h x 16"d. The one with the horn wieghs about 35 lbs. and the other about 30 lbs. They have custom made eminence long throw drivers and titanium tweeter. They are 4 ohms though, so I run the SWR in stereo mode to accomodate that.

I've used this rig everywhere from little bars to concert halls and amphitheaters, and it's performed quite well. Best of all; my entire rig, including bags, cart, and bass fits in the trunk of my Civic.

I'm in the process of changing my rig. I just purchased an Markbass LMII. I'm going to make a series speaker cable to sort out the impeadance issue, though it'll make for an 8 ohm load. I've been mildly gassing for a couple of Bergantino HT 112's, so the LDS cabs may be for sale soon and the SM400S as well.

You're the guy who lives by Lost Nation, Rd. right? I live in Downtown Willoughby, we should get together sometime.

Yup, drop me PM or email. I'd like to check out those cabs.

Thanks.

 

[Ric Vice]

Hello All,
I just discovered this thread today and thought I would post a pic of the design of my LDS 2x8 Three way. The pic I'm using isn't actually my cabinet, but the one that it's based on. Don designed and built the original for Martin Rosenman. I'll post a pic of mine when I get the opportunity to borrow a digital camera.

 

[KJung]

I'd really like to know. Maybe I should call him. Anyway, that's a good NAMED crossover point for those two drivers, done right. The reality is, if done right, named crossover points are kind of a simplicity for what is actually going on though.



That would totally creep me out. Would waste the midrange driver and sound like crap too.



Hey, about letting us know when you find out? ; }

Just curious. Stuff at this level is over my head. Doesn't that 15" speaker have a range up to around 1.8K according to the spec sheet? Wouldn't that suggest that a 1.6K crossover point would make sense? Again, just curious. I would think you would want as much range as you could get out of that big driver, and use the mid speaker for, well, the upper mids (i.e., to just smoothly top off that driver).

I guess I'm assuming that the woofer will be running 'full range', and maybe that is a wrong assumption.

 

[bassplayer7770]

Just curious. Stuff at this level is over my head. Doesn't that 15" speaker have a range up to around 1.8K according to the spec sheet? Wouldn't that suggest that a 1.6K crossover point would make sense? Again, just curious. I would think you would want as much range as you could get out of that big driver, and use the mid speaker for, well, the upper mids (i.e., to just smoothly top off that driver).

I guess I'm assuming that the woofer will be running 'full range', and maybe that is a wrong assumption.

Here was Don's response to me regarding the crossover they're using.

Currently the 15--6.5 uses a high pass circuit, not a 2--way crossover. The freq. at which the board is set is under testing on units already built. We feel that it is correct but because of the frenzy of interest surrounding this design,we are taking a closer look at it. We are also considering some options for players who would like to vary the freq. setting. Stay tuned, we want any changes or mods to improve and add to a users experience positively.

 

[KJung]

Here was Don's response to me regarding the crossover they're using.

Currently the 15--6.5 uses a high pass circuit, not a 2--way crossover. The freq. at which the board is set is under testing on units already built. We feel that it is correct but because of the frenzy of interest surrounding this design,we are taking a closer look at it. We are also considering some options for players who would like to vary the freq. setting. Stay tuned, we want any changes or mods to improve and add to a users experience positively.

+1 Don will be bringing one of these by my house on Wednesday or Thursday. I'll put up some pictures and we will take it through its paces (at least in the basement). I'm looking forward to hearing this design.

And Ralph Patterson makes wonderful crossovers and really knows his stuff. So, I'm sure he and Don have some ideas as they get some experience with these drivers, etc.

 

[bassplayer7770]

+1 Don will be bringing one of these by my house on Wednesday or Thursday. I'll put up some pictures and we will take it through its paces (at least in the basement). I'm looking forward to hearing this design.

And Ralph Patterson makes wonderful crossovers and really knows his stuff. So, I'm sure he and Don have some ideas as they get some experience with these drivers, etc.

And I will look forward to your thoughts!

 

[greenboy]

One of several reasons I would not either cross over high or use a high pass only, showing the smoothed on-axis frequency response of the 3015LF:

Link Removed

The 6ND410 does this area so much better. It's even worse what happens off-axis with the woofer. Here's the pistonic beaming limits of various driver sizes, but they are often beginning to lose decent off-axis response well before that, often as much as an octave lower:

speaker   beaming limit
 size "        Hz
-------   -------------
  18           903
  15          1052
  12          1335
  10          1658
   8          2105
   6          2672
   5          3316
   2          6840
   1         13680

So I want to be off that woofer by 750 Hz at the latest. That's a great reason to use a dedicated small-format midrange driver in the first place: to have better off axis-response as you climb in frequency.

Running the woofer full range and using high pass only to the midrange driver negates much of the improvement the midrange driver brings too; when you have both of them overlapping their output for part of the spectrum and one of them is beamy and doing breakup the imaging becomes murkier and response is uneven and prone to all kinds of artifacting, and one may actually get less SPL for their watt.

Off-axis response should not be minimized either: if that response more closely resembles the on-axis response you get closer to what may be termed equal power response. The benefits of that are that it's often much easier to sound good in a variety of environments and placements and listener postions without as much unsatisfying tweaking trying to deal with room effects. The reverberant/reflected sound is not so varied from the direct source sound, and EQ will be more predictable and positive.

 

[KJung]

One of several reasons I would not either cross over high or use a high pass only, showing the smoothed on-axis frequency response of the 3015LF:

Link Removed

The 6ND410 does this area so much better. It's even worse what happens off-axis with the woofer. Here's the pistonic beaming limits of various driver sizes, but they are often beginning to lose decent off-axis response well before that, often as much as an octave lower:

speaker   beaming limit
 size "        Hz
-------   -------------
  18           903
  15          1052
  12          1335
  10          1658
   8          2105
   6          2672
   5          3316
   2          6840
   1         13680

So I want to be off that woofer by 750 Hz at the latest. That's a great reason to use a dedicated small-format midrange driver in the first place: to have better off axis-response as you climb in frequency.

Running the woofer full range and using high pass only to the midrange driver negates much of the improvement the midrange driver brings too; when you have both of them overlapping their output for part of the spectrum and one of them is beamy and doing breakup the imaging becomes murkier and response is uneven and prone to all kinds of artifacting, and one may actually get less SPL for their watt.

Off-axis response should not be minimized either: if that response more closely resembles the on-axis response you get closer to what may be termed equal power response. The benefits of that are that it's often much easier to sound good in a variety of environments and placements and listener postions without as much unsatisfying tweaking trying to deal with room effects. The reverberant/reflected sound is not so varied from the direct source sound, and EQ will be more predictable and positive.

Makes sense, assuming that mid driver can really handle all that sound without blowing up!

 

[greenboy]

+1 Don will be bringing one of these by my house on Wednesday or Thursday. I'll put up some pictures and we will take it through its paces (at least in the basement). I'm looking forward to hearing this design.

Don't judge my design too much by implementations which are not expecially in keeping with my design goals. They may or may not sound magnificent when you audition... but you will not be hearing my design goals, a large part of which which were to have something relatively transparent so that anyone's chosen tone settings would translate well in a variety of environments in most circumstances.

 

[greenboy]

Makes sense, assuming that mid driver can really handle all that sound without blowing up!

As long as that mid is passed over above 500 Hz or so it can handle just about anything, and do it better and louder than all that gak that comes off of the woofer. It's got incredible articulate presence if not messed up with woofer response crying in the same region, beautiful transients and detail galore, and any EQing (or hidden default preamp voicing) is very revealing and malleable.

 

[KJung]

As long as that mid is passed over above 500 Hz or so it can handle just about anything, and do it better and louder than all that gak that comes off of the woofer. It's got incredible articulate presence if not messed up with woofer response crying in the same region, beautiful transients and detail galore, and any EQing (or hidden default preamp voicing) is very revealing and malleable.

Cool! I guess the key to really doing your design justice is having a crossover available that is voiced exactly as you specify. It looks like that is being worked on over in the other mega thread. Very cool.

K

 

[greenboy]

Cool! I guess the key to really doing your design justice is having a crossover available that is voiced exactly as you specify. It looks like that is being worked on over in the other mega thread. Very cool.

Yeah, actually there are several quality designs people have done, and the Eminence generic two-way crossovers work surprisingly well with the designs too. But I shudder when I hear about high-pass only implementations and variable crossover points in passives. Maybe it's the JBL influence (their better PA stuff is about as good as it gets without selling the farm).

 

[peterpalmieri]

Don't judge my design too much by implementations which are not expecially in keeping with my design goals. They may or may not sound magnificent when you audition... but you will not be hearing my design goals, a large part of which which were to have something relatively transparent so that anyone's chosen tone settings would translate well in a variety of environments in most circumstances.

Are these cabs not utilizing your designs?

 

[KJung]

Are these cabs not utilizing your designs?

We are talking about crossovers here. People are requesting all kinds of stuff and different crossover points and designs from Don at this point, from what I understand. There doesn't seem to be an exact crossover recommendation that is 'fixed' with these drivers in Greenboy's box design at the moment, but I could be mistaken. He can comment on that.

 

[greenboy]

Are these cabs not utilizing your designs?

Somewhat, I think. But what seem like trifling details to some could make big changes. Some just see bigger box, and two drivers of different sizes.

 

[peterpalmieri]

Somewhat, I think. But what seem like trifling details to some could make big changes. Some just see bigger box, and two drivers of different sizes.

I thought a couple of these coming out of Don's shop are the 15/6 design with a crossover at your specs, I guess that's not going to be the case for these cabs Ken is going to try out