Good point I am taking it as sheer impact you know the visceral impact. A pair of 15's, especially depending on box tuning and placement can damn near beat you to death. Especially 100db 1 watt sensitive with kilowatt power handling. That's damn near a 4648 cinema box.Depending on your definition of "punch" it may have nothing to do with the 2245s.
"Kick", "snap", "punch" however you define them can occur at frequencies pretty much all over the map!
Rob
"I could be arguing in my spare time"
This is a sweep with everything hooked up correctly. I think it looks right, the blue is both speakers. I turned up the gain on the bottom amp so it is higher up to the first crossover point. I think it's 290 Hz now.
My 15" woofers did sit about six inches higher in the cabinets than these. I'm going to try to make a pair of stands to raise them.Originally Posted by Ian Mackenzie
As Mr Widget said, these definitely have more finesse than the dual 2226 drivers. When I hooked them up I did like them a lot better. Just playing some songs at insanely high levels the single 18" lost something that the dual 15" had.
Yes, that was my point. The 2202 is much punchier than the 2122 or 2123. Personally, I prefer the 10” woofers, but if my goal was punch, that is where I’d look.Depending on your definition of "punch" it may have nothing to do with the 2245s.
"Kick", "snap", "punch" however you define them can occur at frequencies pretty much all over the map!
Of course, as many here have pointed out, there are many factors to consider, properly operating drivers, proper tuning, room position, personal expectation...
Widget
Now we’re getting somewhere.
Years ago I built a pair of 4355 clones. They really didn’t do it for me… they certainly kicked ass, but I prefer speakers with a more refined capability… that also can kick ass.
I don’t think the 2245 is letting you down, but I don’t think that the 10 inch mid bass driver is ever going to give you a bad ass rock concert in your house if that’s where you’re going. it will certainly get loud, but there’s something about it that doesn’t quite have the slam of a PA system driven hard. The 2202 will give you that. It would be interesting to get Audiohack’s opinion on this as well. He has been known to turn the system up loud occasionally.
Widget
Robert,
My suggestion is to use a process of elimination to finding the cause of your subjective issue.
I generally find if something sounds off that with some work I can isolate and fix the issue. Always trust your ears and assume nothing is ever perfect.
There is a bit to read through below. Use it as a check list in terms of what to look for and what to do about it.
Start by testing the box tuning frequency first. Also test for air leaks around the enclosure.
About box tuning. Check the Fb (box tuning frequency by sweeping a sine wave up and down from 20 - 35 hertz
and observe the point of minimal cone excursion. You can do this by gentle touch. The impedance curve is not
entirely accurate due the driver inductance according to Greg Timbers.
Greg said the tuning frequency should be around 28 hertz. A shade either side of that is permissible.
(that's the way he explained it to me when I built my clones in 2003).
Your enclosure should be lined with one inch fibre glass sheet insulation on five sides and around the Dog box.
If you are using another material that opens up unknown variables. ie the box volume might be smaller than
specified if you are using under felt or foam rubber or pillows.
Positioning. Try re-positioning of the enclosures if that is practical. A trolley board with 4 heavy duty casters works well.
Small incremental movement out from the rear wall can be helpful in obtaining the smoothest bass.
Try raising the enclosure if practical. The combination of horizontal and vertical movement from the wall/floor
boundaries can assist in moderating the worst of most bass response issues.
The bottom on the horn lens should be level with your ears for best imaging.
Measurements. Are you able to describe how you did these measurements?
Distance from the baffle?
Sine wave , Pink noise?
FWIW I have only ever obtained meaningful measurements on my driveway with the enclosures laying on the side (ground plane) using 5 db per division at 2 metres.
The phase cancellation which you might expect at the crossover point is unlikely to be visible if you take a measurement from the listening position inside your home. 10 db per division is not going to show much.
About the phase. Per the 3145 schematic and Giskard's equivalent schematic the mid range array drivers are wired out of phase
to the woofers after the L pads.
JBL specified 18 db slopes in the stock system. The 18 db active slope was chosen because it was the closest
standard filter to the custom 12 db passive filter slopes.
However you are using the 2123H and without knowing your bi amp crossover characteristic you can't
really predict or determine the effect of reversing the woofer electrical phase. The 2123 has a different low
frequency characteristic to the 2122 and requires different associated passive low pass filters to obtain a smooth
response.
So there are a few unknowns and you might advise how your passive crossovers are arranged for the 2123
drivers?
Active crossovers. The thing to appreciate is that most 3rd party active crossovers assume you are using text book drivers.
Unfortunately that is far from the case in this complex four way system where you have substituted out the stock
2122H mid range driver due to it being NLA with the 2123H. Like lots of things in audio everything matters and
the crossover is the heart if your loudspeaker. So its worth getting it right if you can. BTW the dog box should
only be lightly filled with fibre glasinsulation. Too much and it will sound over damped
You might try the 24 db LR filters and wire everything electrically in phase. Listen and see what the measurements look like.
The LR24 crossover is the most black and white crossover function as everything should in theory sum flat with
text book drivers wired electrically in phase. It kind of dumbs it down because the slopes are steep and its a good
compromise when you don't know what's going on in the diy space.
The 18 db filters are the son of a bastard in that they are neither here nor there.
As I hinted at previously I would use a 2nd order low pass filter and a 2nd order butter-worth high pass filter and
listen and measure if you are using the 4344mk11 mid range passive low pass filter.
If your digital active crossover allows custom filters then you can try adjusting the filters crossover point
"spread" until you get a measured null with the woofer electrically out of phase (LR24)(measured at 1 metre) or
electrically in phase (12 db) filters. The centre frequency should be 300 hertz
The subjective effect of acoustic anti phase driver is a thin sounding mid range generally.
I hope these points provide some clarity.
Ian
I heard Elton John last week. Six arrays and wham. That was loud and punchy. They dial in the effects and bingo that crowd goes crazy. Its all very subjective and everyone has their own ear for what turns them on emotionally.
The thing is any SR based system is going to too slam and beat you up. If you like that cool. Bring on the wall of sound.
But are you really craving to get closer to the musicians. I think the slam and punch create that desire.
Turn it up at home. Are you craving for what's missing?
IMHO being front centre stage in a club in SF is more real. The pure tone, texture of the brass and strings, the snare and the growl of the Fender brings on a far more emotional engagement with the sensors.
Set up properly the 4345 ticks a lot of boxes without going financially off the deep end.
Thanks, lots to work with here.
The measurements were taken about 13' from the speakers very close to my sitting position. I used REW and it is a sine wave sweep from what I know. I just used the default. I just started using REW and it is a lot over my head.
The room is 10'6"x21' and I sit at my desk about 15' from the speakers. There isn't really anywhere else to put the speakers, I just could move them away from the walls a bit. They are sitting against the short wall of the room. I could move them to another room that is larger, but I already have two other pairs of speakers in it.
I checked the tuning with my hand and it seemed like it was 28 Hz. I did this before you posted this. The cabinets dimensions match the plans posted here. They are lined with 1" fibreglass on five sides. The fibreglass is stiffer than home insulation, I believe it was made for insulating ducts. There is 1" insulation on five sides of the dog box also. There shouldn't be any leaks in the boxes, my carpentry skills are a lot better than my speaker tuning skills.
I am using an Xilica XP4080, so it has lots of choices for crossover slope, filters etc.
The 2251Js (~9.75") have punch. I attribute it to the light cone and accordion edge working with the differential drive to create a fast transient response.
The horns are 6 ft apart. I have a couch in the room also, so moving closer to the speakers would be difficult I want to keep the couch as far from the speakers as possible. I still like the idea of lifting them.
Hi Robert,
I have been looking at some of your earlier threads and posts.
Getting back to your question a pair of 2226 a side is one very potent mid bass system with very sensitivity of over 100 dB. That might serve a number of applications in the SR industry.
The 4345 is not going to complete with that in the way you might be used to with the 2 pairs of 2226 drivers. If you are wedded to that presentation l recommend you look up Drew’s Clues in the Library on ideas to enhance what you like.
For example you might move this rig back into your larger room and end up with 2 x 18 inch 2245 (or 2242) subs per side 25-100 hertz , dual 2226 mid bass drivers 100-500 hertz , a single 2123 driver 500-1200 hertz, your 2440 driver 1200-8000 hertz, your slot 8000-20000.
This approach is building out and enhancing the dual 2226 approach by limiting the 2226 operating bandwidth to its optimal range and supplementing it above and below with other drivers.
That l think is what your really on about.
The idea of the 4345 is an accurate (1980 era) mastering monitor which it does well.
Replacing the 2245 with the 2242 is going to give you more of what the 2245 does.
You could also try the 2245 in your larger room at some point.
2242's would be a mistake, as would 2240s. 2241H is the better way to go, especially if you have a big cabinet (10+ cu ft). But these will also work in a much smaller cabinet (down to 5+ cu ft). Run the WinISD simulations to convince yourself that there is no contest.
I use them in the Ethyl Mermans and they have a whole he-- of a lot more slam than the AlNiCo 2235s in the L300s.
If you want a good track to assess "slam," listen to a high quality recording of the drum track at the opening of Billie Jean by MJ. With a bit of volume it should kick you in the chest and about knock you out of your chair. Don't expect it on the YouTube video over you computer.
https://youtu.be/Zi_XLOBDo_Y
2241 makes a far better "subwoofer" than a 2242.
I use 8 mH/95 mfd with a 100 mfd/1.2 ohm Zobal on my 2241s. Run the simulation and you will see thats' subwoofer territory. 2242s would peak higher up. Again run the WinISD simulations and convince yourself.
BTW, 2242s are not true subwoofers even though they were marketed that way to theaters. Just look at their specs.
A picture is worth 1,000 words. 2242 is a "subwoofer" in name only.
2241H in green and 2242H in red from WinISD:
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