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rbnjr
02-29-2016, 12:04 PM
Are there any recommendations on equipment that would best match the L300 summit speaker?
no budget constraints.

thank you.

speakerdave
03-08-2016, 05:48 PM
Something to be aware of: In the 4333a, which was factory wired biampable, the signal shaping and frequency division elements of the high pass were left in the circuit when switched to biamp mode. Also the zobel was left across the woofer. These were done because both were necessary to achieving the design goal frequency response of the system as a whole. Therefore the external crossover only needed to provide low pass at 800Hz. As I recall, the L300 was not built biampable. The answer to your question depends in part on what modifications you have made to make yours biampable.

rbnjr
03-08-2016, 06:03 PM
Something to be aware of: In the 4333a, which was factory wired biampable, the signal shaping and frequency division elements of the high pass were left in the circuit when switched to biamp mode. Also the zobel was left across the woofer. These were done because both were necessary to achieving the design goal frequency response of the system as a whole. Therefore the external crossover only needed to provide low pass at 800Hz. As I recall, the L300 was not built biampable. The answer to your question depends in part on what modifications you have made to make yours biampable.

as of this date i have not made any crossover mods to the L300. I wonder if the 4333a has similar design elements and the 4333a crossover will be able to be used.

thank you.

speakerdave
03-08-2016, 06:21 PM
It's the same speaker.

tonymontana168
10-26-2018, 01:17 PM
Hello I have original L300 with nelson pass xo but only for the highs. for the sub I am active. I have 2 amps. I have 2 outputs on my preamp!
1 output goes to active crossover that has a 24db slope!
2nd output goes to the nelson pass passive xo and does to mid and tweeter.

BUT BUT... I think the nelson pass is 12db octave and my electronic active crossover is 24db oct.

Is that bad? should I be using my second output on my preamp?
Should I cross my active crossover at 1200hz? 800hz? Im really lost. It sounds good but not like it used to with original xo and active at 800hz.

Should I cross it at 1200hz now? should I get another active xo that has -12db oct slope?
I take mesurements but many people say they are not accurate here is the pic of high low and full range frequencys

Mr. Widget
10-26-2018, 03:12 PM
Im really lost.I see that. ;)

Oh, welcome to the Lansing Heritage Forum!

What you are trying to do requires a fair amount of knowledge, skill, and patience if you want it to sound better than stock. Do you still have the parts to return it to original? If you do, I’d suggest you get it back to stock and then you can take a measurement of the stock system at 6’ or so. It’s important that you carefully balance the mid and tweeter l-pads to make the system as flat as possible.

If you still feel compelled to mess around with your speakers, keep this measurement as a baseline and have at it.

Regarding your question about slopes and crossover frequency, in some ways there is no wrong answer as long as you don’t damage anything and you like the results. I would try to get it to work with a 800Hz crossover frequency. Also if you hear highs coming from the woofer at an appreciable level, you’ve likely hooked up something incorrectly.


Widget

rbnjr
10-27-2018, 06:14 AM
It's the same speaker.

your reply indicates you do not have a clear image of my design concepts. other jbl speaker crossovers may work in the L300 and models with bi amped cross overs are the ones im looking for.

macaroonie
10-27-2018, 10:13 AM
I am of the opinion that while the L300 / 4333 is a great speaker in it's original form , with modern DSP crossovers etc it can rise to another level not attainable with passive
networks.
To get there forget about the old crossovers and trying to integrate them with electronic filtering. I can be done but it not an elegant solution

You did mention in your original post the there were no price constraints , however
I will give you a bobby basic line up that will do your job.

DBX260

stereo power amps x3

6 core speaker cable

protection caps for the MF and HF drivers. There is a little table published by JBL which I have. I'll post that later

You know the x/o frequencies and slopes so you can copy that in the software of the X/O as a starting point.

Simply put the x/o will give you LF MF and HF outputs that you then allocate to the power amps. You absolutely need to keep track of your hook ups TAKE NOTES !!

In the L300 the mid horn driver as I recall is out of phase with the bass unit but you will not need to do that as the delay available in the x/o will allow you to do that digitally.

From there on in it's a matter of getting the basics set up and running then you can start refining the system bu using measuring tools . The X/o has loads of EQ options
that you will need to learn to get things dialed in properly. It will take you a while but straight out of the gate you will notice a significant improvement in dynamics , clarity , imaging etc . Almost as good as having you ears syringed :)

Read this: http://www.audioheritage.org/vbulletin/showthread.php?17238-Backyard-Box-Building-The-Build

I was able to lower the LF/MF crossover point to about 650Hz but I had provided for that with the bigger horn and a 2" driver. The 2235H is not really that well suited ti playing at 800Hz.

82625

82626

tonymontana168
12-23-2018, 09:49 PM
triamp is really amazing I just put caps for protection and wow what a difference it made so much clarity! I crossed at 800 and 8500@24db with the new 3Rd Gen sublime crossover. it's great at the price. the bass really slames and goes really deep. I am using my 3 McIntosh amps 2x mc2200 and 1x mc2120 for my 4x tweeters 077!
I added 2 rear fire in 077 (ambience tweeters)

Alobar
12-30-2018, 11:53 AM
I am of the opinion that while the L300 / 4333 is a great speaker in it's original form , with modern DSP crossovers etc it can rise to another level not attainable with passive
networks.
To get there forget about the old crossovers and trying to integrate them with electronic filtering. I can be done but it not an elegant solution

You did mention in your original post the there were no price constraints , however
I will give you a bobby basic line up that will do your job.

DBX260

stereo power amps x3

6 core speaker cable

protection caps for the MF and HF drivers. There is a little table published by JBL which I have. I'll post that later

You know the x/o frequencies and slopes so you can copy that in the software of the X/O as a starting point.

Simply put the x/o will give you LF MF and HF outputs that you then allocate to the power amps. You absolutely need to keep track of your hook ups TAKE NOTES !!

In the L300 the mid horn driver as I recall is out of phase with the bass unit but you will not need to do that as the delay available in the x/o will allow you to do that digitally.

From there on in it's a matter of getting the basics set up and running then you can start refining the system bu using measuring tools . The X/o has loads of EQ options
that you will need to learn to get things dialed in properly. It will take you a while but straight out of the gate you will notice a significant improvement in dynamics , clarity , imaging etc . Almost as good as having you ears syringed :)

Read this: http://www.audioheritage.org/vbulletin/showthread.php?17238-Backyard-Box-Building-The-Build

I was able to lower the LF/MF crossover point to about 650Hz but I had provided for that with the bigger horn and a 2" driver. The 2235H is not really that well suited ti playing at 800Hz.


Extremely timely post here! I am getting ready to order parts to fully triamp my L200A's (which have 077's added). My current setup is this:

Running biamped with the LE85 (16 ohm Radian diaphragms) using the LX16a passive for the mid as protection. The 077 is currently using a 1uf cap and 8 ohm Lpad by itself, and the old LE15B's have been replaced with 2216Nd1's and they are running direct from a 170wpc power amp, crossed at 1150hz using a MiniDSP 2x4HD. The difference with biamping with the DSP and the 2216Nd1 has been nothing short of thrilling compared with the stock L200's..

What I want now is to completely get rid of the LX16, and triamp these speakers. To that end I have on order a MiniDSP 4x10 HD, extra speaker wire etc. Where I am slightly stumped is the JBL ratings for nominal impedance. JBL literature says both the LE85 and the 2405 are 16 ohms. I am assuming the 077 is the same as the 2405, but I have read in different threads that the impedance for both these drivers actually run less than 16. Is there a definitive answer for this for the purpose of ordering protection caps as well as the recommended shunt resistors? Should I assume 16 ohm or go less for this purpose?

I plan to keep the crossover point for the Low/Mid at around 1100-1150 as the 2216Nd1 seems very capable of playing that high and I really like the sound..
Thanks for any advice on the caps!

Earl K
12-30-2018, 02:34 PM
Here'san ancient post of mine (http://www.audioheritage.org/vbulletin/showthread.php?20214-Question-on-N7000-N8000-XO&p=203312&viewfull=1#post203312) authored under fairly similar circumstances.

I used both of Zilch's & Widgets previous impedance studies to illustrate the real impedance's ( to your question ).

http://audioheritage.csdco.com/vbulletin/attachment.php?attachmentid=10030&stc=1&d=1126855672

If you use the search function ( with Zilch as author ) & impedance as the word of interest , there are numerous graphs created by him show that impedance is a curve ( so one simply gets to make their choice of Frequency vs Impedance & then go from there ).

An interesting post from Zilch comparing 6 le85's on 2307 horns (http://www.audioheritage.org/vbulletin/showthread.php?13050-The-2425Js-Are-SWEET!-but-what-Horn-did-I-get&p=135642&viewfull=1#post135642)

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=20912&stc=1&d=1164610728

:)

PS; ( click the pic )

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=19819&stc=1&d=1161587006 (http://www.audioheritage.org/vbulletin/showthread.php?12522-L-200-woofer-changes&p=128226&highlight=le85#post128226)

Earl K
12-30-2018, 05:13 PM
Well it occurs to me that you really just want a simple answer ( without the details as to why ).

So, here it is .

Use a 20 ohm parallel ( conjugate ) resistor across the le85.

Insert inline a 52 uF cap between the amp and the driver/resistor combo.

- ( going smaller than 52uF will detrimentally effect the FR response by attenuating it too much in the crossover region ).

BTW; even 52uF attenuates the 1K region by 1.5db .

:)

Earl K
12-30-2018, 05:16 PM
Here are the details as to why to use the above.
- ( red shows the effects the suggested circuit ,,,,,, IOW> even 52uF doesn't leave the crossover area completely untouched )

:)

Alobar
12-30-2018, 05:56 PM
Well it occurs to me that you really just want a simple answer ( without the details as to why ).

So, here it is .

Use a 20 ohm parallel ( conjugate ) resistor across the le85.

Insert inline a 52 uF cap between the amp the driver/resistor combo.

- ( going smaller than 52uF will detrimentally effect the FR response by attenuating it too much in the crossover region ).

BTW; even 52uF attenuates the 1K area by 1.5db .

:)
Thanks much Earl, that really was all I needed as most speaker specific details can go over my head pretty fast usually, and you guys have so much experience! That takes care of the LE85, so was wondering if you have any thoughts on the Cap/Resistor for the 2405/077? Want that crossover point to be around 7 or 8khz.

Earl K
12-31-2018, 04:07 AM
Thanks much Earl, that really was all I needed as most speaker specific details can go over my head pretty fast usually, and you guys have so much experience! That takes care of the LE85, so was wondering if you have any thoughts on the Cap/Resistor for the 2405/077? Want that crossover point to be around 7 or 8khz.


An XSim shows that a 6uF capacitor followed by a 20R resistor ( wired across the 077 ) is very effective ( at leaving the response mostly untouched but still protected from DC ).


:)

Alobar
12-31-2018, 11:21 AM
An XSim shows that a 6uF capacitor followed by a 20R resistor ( wired across the 077 ) is very effective ( at leaving the response mostly untouched but still protected from DC ).


:)

Thanks very much, and a very Happy New Year as well!

Alobar
01-16-2019, 11:35 AM
An XSim shows that a 6uF capacitor followed by a 20R resistor ( wired across the 077 ) is very effective ( at leaving the response mostly untouched but still protected from DC ).


:)
Earl, again thanks for your help! I got all the protection caps and the resistors in place as per your recommendations. Just wanted to say I have my system fully triamped and am just amazed how much better, more clear they sound now! The veil is lifted would be one way to describe.. This triamped mod has done every bit as much to the mids and HF as the 2216Nd1's did for the LF and MF. I am still dialing it in but am close to happy with it. There are only 5 PEQ slots (stereo) on each output of the MiniDSP 4x10HD and another 5 on the input side so that has forced me to keep editing existing ones instead of just adding more. I have got it somewhat flat down to 20hz now, with a 400-800hz dip (this has always been a stubborn area in my room) but for it just being a day or so since I started I think I can fix that.

One thing I would like is some guidance about the crossover settings themselves, the slopes, crossover points etc. How to dial it in correctly. My current settings are:
LF: High Pass 20hz cutoff LR 48db. Low pass cutoff 1150hz BW 24db.
MF: High Pass 1200hz cutoff BW 24db. Low Pass 8500hz BW 18db
HF (077) High pass cutoff 8500hz BW 36db.

I moved the LE85 crossover point from 1150 to 1200 to ease a slight edgyness in that region which did the trick without losing anything. Also I have the 2216Nd1 running reversed polarity as they seem to dig just a little cleaner and deeper that way. The LE85 is straight polarity and the 077 may be reversed from before can't remember (hard wired) when I was running it passive on a 1uf cap and 8 ohm L pad which is now gone..

Anyone who has any suggestions on further improvements or things to try I would be grateful.. Also I know running the 2216Nd1 to 1150 hz is quite a bit higher than what the 4367 xover point is, but it just sounds so good and seems to be able to deliver it just fine.

Right now I just can't stop listening to these old speakers! Stayed up till midnight last night listening.. :bouncy:
83170

Ian Mackenzie
01-16-2019, 03:18 PM
Wow you are having fun.

Glad you are getting a subjectively good result.

On the crossover frequency there are a few technical ideas around what should work best but it’s sll about your ears. Let them be the judge.

What you are juggling is the phase continuity between the woofer and the horn and matchup of the woofer dispersion with the horn.

The better these two criteria are the better it will sound in the listening window not just dead on axis.

If it’s out of whack when you move the listening position slightly the frequency response will turn ugly in the crossover region.

You may be able to measure the real time displacement between the woofer and the horn and adjust this with the mini dsp. However the true test of phase tracking at the crossover point is when the phase is reversed there should be a uniform 20 dB notch you can measure on axis with the horn ie your listening height.

The hl92 horn is about 300 mm deep plus 70 mm to the driver voice coil =370 mm.

Less about 70 mm from woofer voice cool gives around 300 mm +- 25 mm physical
displacement. The distance between the driver voice coils is only an approximate acoustic centre distance. If you simply try can get a smooth crossover point with everything in phase that won’t work subjectively. A wavelength at 1200 hertz is 286 mm. So with that wavelength you may find a 24 dB slope at 1200 hertz works. The actual electrical phase will depend on whether you have used delay on the woofer or not. These numbers are all an educated guess.

As l said use the reverse polarity test and move the crossover point up or down until you get a nice notch. The level of both drivers should be closely match in the crossover region. So get the slopes as close as possible first with the overall levels before doing this test.
It will sound really good after you flip the polarity back to normal.

On the dispersion match the woofer is possibly a good match for the horn at 1200 hertz.

But you can confirm this by measurement of the frequency for a -6 dB spl off axis at say 45 degrees off axis for both the woofer and the horn. That will in theory sound more like seemless crossover between the woofer and form.
Of course the woofer has to like that frequency or it may sound like crap.

With the slopes there is bit of ambiguity on what is what. The slope always refers to the combination of the drivers natural response and the addition of the crossover filter.

For example if you programmed in 24 dB slope on the horn high pass filters at 1200 hertz the actual slope might actually be more than a 24 dB slope. If the mini Dsp can give you an Objective curve to adjust to that will help. The steeper the slope the less off bad behaviour you will get from the horn and woofer. If you can get an acoustic slope of 24 dB on both drivers stick with that. Otherwise consider 18 dB.

Alobar
01-17-2019, 01:10 AM
Wow you are having fun.

Glad you are getting a subjectively good result.

On the crossover frequency there are a few technical ideas around what should work best but itís sll about your ears. Let them be the judge.

What you are juggling is the phase continuity between the woofer and the horn and matchup of the woofer dispersion with the horn.

The better these two criteria are the better it will sound in the listening window not just dead on axis.

If itís out of whack when you move the listening position slightly the frequency response will turn ugly in the crossover region.

You may be able to measure the real time displacement between the woofer and the horn and adjust this with the mini dsp. However the true test of phase tracking at the crossover point is when the phase is reversed there should be a uniform 20 dB notch you can measure on axis with the horn ie your listening height.

The hl92 horn is about 300 mm deep plus 70 mm to the driver voice coil =370 mm.

Less about 70 mm from woofer voice cool gives around 300 mm +- 25 mm physical
displacement. The distance between the driver voice coils is only an approximate acoustic centre distance. If you simply try can get a smooth crossover point with everything in phase that wonít work subjectively. A wavelength at 1200 hertz is 286 mm. So with that wavelength you may find a 24 dB slope at 1200 hertz works. The actual electrical phase will depend on whether you have used delay on the woofer or not. These numbers are all an educated guess.

As l said use the reverse polarity test and move the crossover point up or down until you get a nice notch. The level of both drivers should be closely match in the crossover region. So get the slopes as close as possible first with the overall levels before doing this test.
It will sound really good after you flip the polarity back to normal.

On the dispersion match the woofer is possibly a good match for the horn at 1200 hertz.

But you can confirm this by measurement of the frequency for a -6 dB spl off axis at say 45 degrees off axis for both the woofer and the horn. That will in theory sound more like seemless crossover between the woofer and form.
Of course the woofer has to like that frequency or it may sound like crap.

With the slopes there is bit of ambiguity on what is what. The slope always refers to the combination of the drivers natural response and the addition of the crossover filter.

For example if you programmed in 24 dB slope on the horn high pass filters at 1200 hertz the actual slope might actually be more than a 24 dB slope. If the mini Dsp can give you an Objective curve to adjust to that will help. The steeper the slope the less off bad behaviour you will get from the horn and woofer. If you can get an acoustic slope of 24 dB on both drivers stick with that. Otherwise consider 18 dB.

Thanks Ian, your post makes sense and you have given me a lot to digest.. I'm probably going to work on it evenings for the next month or so, and will report back on my luck.. Meanwhile I think the sound is so much better now than before, if I stopped today I would be happy. Just want to get it as good as I can!

Ian Mackenzie
01-17-2019, 02:04 AM
I agree. Itís all relative.