2215s/2231s

[kawasakitech]

Does any one have experience with the 2215?
What is the sound like compared to a 2231?
Right now I have 2205s reconed with unknown kits.
Trying to get a bit more low bass.
What is recommended as maximum crossover point for both drivers.
I see that the 2215 falls off before 1khz where the 2231 rises.
I have 2425s as well as 2447s as an option for the top end.
Trying to stick to a 2 way format in a sealed cabinet to minimize colouration.

Thanks

[Mr. Widget]

Does any one have experience with the 2215?
What is the sound like compared to a 2231?
Right now I have 2205s reconed with unknown kits.
Trying to get a bit more low bass.
What is recommended as maximum crossover point for both drivers.
I see that the 2215 falls off before 1khz where the 2231 rises.
I have 2425s as well as 2447s as an option for the top end.
Trying to stick to a 2 way format in a sealed cabinet to minimize colouration.

ThanksI've used all of these woofers... well, 2235H instead of 2231, but I've used the others. They are all colored in their sound as are all speakers. :) These JBL woofers all need to be used in ported enclosures to really work properly. I would not recommend using them in sealed boxes in an attempt to better the factory designs. Better built boxes using more "correct" tuning frequencies can help.

The 2235H is the most neutral and goes the deepest of the bunch. You can re-cone your 2205s to 2235As to good effect. I recommend a 5 cu ft box tuned to 30Hz. I would use fiberglass or cotton denim insulation as damping material. The boxes can't be too rigid. Use plenty of hardwood bracing if possible.


Widget

[kawasakitech]

I know the standard response is to use a sealed cabinet.;)
I now have 2205s (reconed) in a sealed 8 cu ft cabinet.
This was recommended to me by Philip Newell (Who wrote a book with Keith Holland about studio monitor loudspeakers).
"Loudspeakers for music recording and reproduction"
I prefer the clarity of this as opposed to the "ringing" bass from the vented cabinets.:)
I hear much more detail in and through the bass as well as better transparency throughout the frequency range.:D
Philip recommended the 2231/2235 in a sealed cabinet as well.;)
He explains it all in his book with excellent analogies and diagrams.
I will use "sand filled" walls on my new cabinets as planned/posted on other threads.:banghead:
Thank you for your reply/opinion
What is your experience/opinion of the midrange region of these drivers 800-1.2khz (2215/2231/2235):confused:
Thanks

[4313B]

Well... You might want to look at a Linkwitz Transform to EQ the 2235H in a sealed box. :dont-know: Be aware that the xMech on the 2235H isn't real stellar compared with low frequency transducers of today.

Subwoofer equalization - Linkwitz Lab (http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=3&cad=rja&sqi=2&ved=0CEAQFjAC&url=http%3A%2F%2Fwww.linkwitzlab.com%2Fthor-eq.htm&ei=pW6TUqu-B8broAT1loCYDw&usg=AFQjCNG2bwJ8C3-tVBG9v5FP2xA6KEuHeg&bvm=bv.56988011,d.b2I)

Linkwitz Transform Subwoofer Equaliser - Elliott Sound Products (http://sound.westhost.com/project71.htm)

Linkwitz Transform | MiniDSP (http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=5&cad=rja&sqi=2&ved=0CEwQFjAE&url=http%3A%2F%2Fwww.minidsp.com%2Fapplications%2F advanced-tools%2Flinkwitz-transform&ei=pW6TUqu-B8broAT1loCYDw&usg=AFQjCNFtQCwfMR7UvEwtCm1XAf1CEHJvCg&bvm=bv.56988011,d.b2I)

I wouldn't bother with the older 2231 as it is arguably too overdamped, although Mark Gander did propose using it in a 5.0 cubic foot sealed box stuffed full of little fiberglass squares back in the late 70's and early 80's.


JBL used the 2235H up to 1 kHz in the 4430/4435 Studio Monitors to good effect.

[kawasakitech]

4313B
Thank you for your reply
I don't really want to go the route of equalization as EQ trades off uneven frequency response for phase response anomalies.
This causes more problems than it solves.
See "Loudspeakers for Monitoring and Sound Reproduction" by Philip Newell and Keith Holland for a better explanation than I can give you.
I also don't want to go the DSP route as first of all it always sounds wrong to me, I don't really know what is wrong but I know it's wrong.
Also DSP opens up the can of worms of the quality of the DA/AD converters.
Good quality converters are expensive and most digital signal processors are inexpensive, explain that to me.
Then again lots of people listen to Bose audio and PA and love it,It all sounds terrible to me.
I prefer analogue, electronic crossovers and simple circuitry.
And of course JBL/Altec

[1audiohack]

4313B
Thank you for your reply
I don't really want to go the route of equalization as EQ trades off uneven frequency response for phase response anomalies.
This causes more problems than it solves.

Im not going to jump into the "To EQ or not to EQ" thing. However an hour spent with an FFT meter, and an EQ would prove that the above blanket statement is in simply untrue.

Barry.

[fpitas]

Since drivers are more or less minimum phase devices, a proper EQ will also result in a smooth phase plot. It's a common internet buzz that EQ causes phase anomalies, but makes no mathematical sense. It also disagrees with my own experiments, where smooth frequency response gives smooth phase response. Perhaps people are trying to EQ non-minimum phase systems for room effects, and getting (understandably) weird results.

[kawasakitech]

There is always a phase shift from any type of EQ.
I'll get back to you on this with quotes from Philip Newell/Keith Holland

Bloys

[fpitas]

There is always a phase shift from any type of EQ.
I'll get back to you on this with quotes from Philip Newell/Keith Holland

Bloys

Yes, there is. But if you're doing it right, you're cancelling an equal but opposite phase shift caused by the frequency deviation you're EQing.

[1audiohack]

There is always a phase shift from any type of EQ.
I'll get back to you on this with quotes from Philip Newell/Keith Holland

Bloys

Hi Kawi;

It appears by this and other posts that you study and are largely influenced by the sound studio designs, yes?

Rather than quotes, how about real world measurements with FFT screen shots and explanations? If you are interested there are a couple of very good articals on the subject of creating crossovers with proper and necessary EQ methods to get good on and off axis response curves in both frequency and time.

Some food for thought: There is EQ built into all speakers and speaker systems, somewhere. Some of the obvious variables would radiator diameter, resonant frequency, cone mass, cone shape, compliance, coil inductance, coil height, magnetic gap height and magnetic gap flux strength in addition to the crossover components either physical components and or electronic filtering and of course the enclosure.

It has been mentioned that EQ (properly applied) to a devise (no matter the method) within its linear band of operation actually corrects both the frequency and phase response and that is absolutely correct. While it is generally understood that frequency and time are inseperably tied together and in reality are the same thing as viewed through two different lenses, is that magnitude and phase are also tied together, as viewed through an FFT measuring apparatus. For example, of you decrease the volume of the midrange driver in a three way speaker system, no matter how you do it, with a resistor, a higher resistance voice coil, a graqhic equalizer, with a parametric EQ, or simply attenuating the input sensitivity of the amp driving it in a multi amp system, you create a dip in the phase response. In a linear system, any ripple in one domain will have a corresponding wrinkle in the other.

If your interested I will lookup and link the afore mentioned articals.

All the best.

[kawasakitech]

1audiohack
I am trying to get accuracy/sound quality, that is why I am going this route.:banghead:
I am sorry but I don't have measuring/FFT equipment or the skill to use it.
I have to rely on what people say and what I hear.
I would be interested in the articles.
I have always preferred the sound of large low Qts bass drivers and horn mid/tweeters as opposed to the modern small inefficient bass driver with a soft dome tweeter.
I like the dynamics and the large clear midrange.
I also want to get an accurate natural drum kit reproduction.:rockon1::rockon1:
That EQ is built in I will accept but it does not cause phase shift in the input signal.
Thank you

Bloys

[frank23]

I am with you on the DSP/AD/DA subject. I have put a topic somewhere on this forum about modding my JBL M553 LR crossover by removing most of the coupling caps. It has been playing fine ever since. I also don't use any caps between my amps and drivers. For ultimate sound quality, analog and the least caps possible is the way to go. Even if that results in a not-perfectly flat frequency response.