Page 2 of 5 FirstFirst 1234 ... LastLast
Results 16 to 30 of 75

Thread: 3-way vs. 4-way

  1. #16
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,170
    With the benefit of experience and hindsight l would not do a 2123 under a deep horn
    Hello Ian

    I would not either I was thinking the 2234. Like you were saying the 15" directivity will help minimize the reflections off the horn. If he was hell bent on the 2123 I would suggest he ditch the 2441 and use a modern 1.5" throat driver with an aguaplas diaphram on a shallow waveguide.

    Rob
    "I could be arguing in my spare time"

  2. #17
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,942
    Zactly

    If he wants a wall of sound aka a PA then whatever

    Hell why not but a pair of Great Plains 604’s ?

    It’s fail safe for a beginner

  3. #18
    Senior Member
    Join Date
    Sep 2008
    Location
    Germany / Hamburg
    Posts
    659
    Thanks a lot for these declarations!

    I like the idea of keeping the acoustic centers of the drivers close to each other to minimize group delay and phase problems.
    The 2234 has a steeper e.g. deeper cone than the 2123, I get you. But this difference might be ~5cm, so most of the offset to the horndriver still remains. So I would think their shouldn´t be a big difference between 2234 and 2123 concerning the offset-issue, or did I miss anything?

    I believe the reflections of the 2234 or 2123 underneath the horn would make a much bigger difference.
    The narrower the dispersion of the cone driver, the less reflections will bounce of the bottom of the horn. So the 15" woofer should be clearly in advantage here.
    You said the dispersion of a 15" woofer around 1khz should be around 100°. What about a 10" woofer at 1khz for comparison?



    We are not tied to the 2123´s, if it doesn´t make any sense we will sell them.

    There is only the chance to mount one 15" driver because of the size, so no 4435 clone on the bass department...

  4. #19
    Senior Member
    Join Date
    Sep 2008
    Location
    Germany / Hamburg
    Posts
    659
    I found this picture with google...
    The yuichi horn protrudes a fair bit, would this be ok?
    Would you mount the 15" woofer a bit lower to increase the distance to the horn, or can woofer and horn be mounted closely against each other?

    Name:  yuichi horn..jpg
Views: 1314
Size:  254.1 KB

  5. #20
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,597
    "Or the 15" woofer sounded muddy running up to 800hz in the 3-way and the 10" midwoofer in the 4-way gained a lot of liveliness to the speaker."

    This is what I've found and the 2235 starts to get "rough" and looses a bunch of volume around 250Hz. I actually have a null at 250 Hz caused by???

    "You can get rid of the 2123, but then you loose in "guitar type" instrument reproduction and Low voice dimension."

    This is also the case, especially with acoustic guitar.

    What is not mentioned is that you also loose intelligability, imaging, and soundstage because some of the frequencies that provide these cues are MIA.

    I have my L200/300s set with a 2251H, open baffle, on the "B" speaker with a 35 mfd cap and I'm thinking 47 mfd would be about perfect into this 16 ohm load. I can "dial" in the volume to this speaker and A/B with/without it. The difference is very real and what is seen on the RTA confirms the audible differences. Without the 2251s, the sound/image just "falls flat on its face" (get more mono with less depth). The 2251 picks up where the 2235 tails off at about 250 Hz.

    When I receive my new DMM, I'll be able to measure Henrys and can set the upper limits on the 2251s.

    Anyone is welcome to come over to my house to hear the difference for themselves. I live in Orange County, CA.

  6. #21
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,703
    Quote Originally Posted by toddalin View Post
    "...."

    This is what I've found and the 2235 starts to get "rough" and looses a bunch of volume around 250Hz. I actually have a null at 250 Hz caused by???

    ...I live in Orange County, CA.
    Hi tod...,

    Have You tried the measurements of the 2235H putting the speaker box laying back side on the floor and hanging mic 1 m over it.
    I can imagine the mentioned 250Hz (phase difference about 69cm) notch is influenced by the floor driver 'image' , or try to lift the box bottom over 0.5m from the floor surface.

    regards
    ivica

  7. #22
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,597
    Haven't tried that.

    The 10" sitting on top of the L200 cabinet gets it well above this level and largely addresses the problem, if that is in fact the cause.

  8. #23
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,942
    Tod

    Have you compared the 2235 with the 2234

    Like complete the 430 to the 4435

    The 4435 is is totally different loudspeaker in the midrange

  9. #24
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,597
    No, and that is why I advocate leaving the mass rings out and just using a sub, under the assumption that the removal of this weight would help the midrange situation.

  10. #25
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,942
    Quote Originally Posted by Dr.db View Post
    Thanks a lot for these declarations!

    I like the idea of keeping the acoustic centers of the drivers close to each other to minimize group delay and phase problems.
    The 2234 has a steeper e.g. deeper cone than the 2123, I get you. But this difference might be ~5cm, so most of the offset to the horndriver still remains. So I would think their shouldn´t be a big difference between 2234 and 2123 concerning the offset-issue, or did I miss anything?

    I believe the reflections of the 2234 or 2123 underneath the horn would make a much bigger difference.
    The narrower the dispersion of the cone driver, the less reflections will bounce of the bottom of the horn. So the 15" woofer should be clearly in advantage here.
    You said the dispersion of a 15" woofer around 1khz should be around 100°. What about a 10" woofer at 1khz for comparison?



    We are not tied to the 2123´s, if it doesn´t make any sense we will sell them.

    There is only the chance to mount one 15" driver because of the size, so no 4435 clone on the bass department...

    There is a lot more to it can l have discuss here

    At lower frequencies the phase shift or group delay had a bigger impact

    When we look at 700 hertz the acoustic centre of the woofer and the combined group delay of the low pass filter on the crossover results in a far better situation than attempting the 2123 at 1000 hertz or above

    In terms of the suitable woofer no one is complaining about the 2216 in the M2

    Tad go a step further with a sharper crossover slope of 36 dB that also introduces more group delay

    Remember the A290 is a hypex horn and they are longer than the typical exponential horn

    Tad monitoring has a reputation for a reason

    The alternative if you think you must use the 2123 is mount it on. Pi mid wood horn for 200-1000 hertz

    If you intend to use the 2123 then consider a different horn specifically design for a 1200 crossover point

    That will have far less depth by design in a modern wave guide

    There are lots of options

    Frankly if you get the 2234 in there it’s pointless

  11. #26
    Senior Member
    Join Date
    Sep 2008
    Location
    Germany / Hamburg
    Posts
    659

    Hyperbolic vs. Exponential

    The A-290 is a Hyperbolic-Horn, but there is an Exponential-Horn called A-300 as well.
    How would these differ in sound and which of these is to be favoured?

    I know it´s hard to tell without any measurements, but how big should the offset be between the 2441 driver and 2234 cone with a 12db crossover at ~700hz ?
    Would it be a perfect match like on this photo here?
    Probably not, because this is like the TAD monitors and their 36db crossovers introduce more delay than my 12db filter...
    Name:  yuichi horn..jpg
Views: 1061
Size:  254.1 KB

    So I would probably have to put the 2234 even further behind to match with the deep yuichi horn?
    Would it be a smart idea to build something like a waveguide for the 2234? Similar to the Tannoy westminster, even knowing it´s a horn on the tannoy... But I wouldn´t have a clue how to determine the correct curves and angles for the waveguide... maybe a 45° phase on the side´s & top and a straight edge for the bottom!? But I think this will be unpredictable diy-nonsense...
    Name:  Tannoy-Westminster-GR.jpg
Views: 1122
Size:  71.6 KB


    @ivica:
    Did you successfully use a l300 crossover with an 2" 2441 driver in the past?
    Did you have to change anything, because this network was initially for the 1"-drivers...?

    @Todd:
    In which bandpass did you use the 10" cone with your L300 ?
    Was your 15" a 2235 or 2234?

  12. #27
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,597
    I am currently using a 47 mfd cap (common value) to filter out the lows and only bring the unit up enough to "hear the difference." This puts the crossover point at ~210 Hz with the 16 ohm load. I need to work out the upper limit based on testing with the Heil. If possible, I will also keep both of these as 1st order.

    For 2241H, I have a pair of 3115 crossovers. These have a 6 mH choke, 27 mdf to ground and 13.5 mfd through 10 ohms to ground (Zobal).

    A 1st order Butterworth crossing over at ~210 Hz uses 6 mH to the 8 ohm load. Alternatively, I can change the caps values to alter the slope.

    My 15's are AlNiCo 2205s reconed as a 2235s with the mass rings added. These are factory JBL cones and the work was done by Orange County Speaker. The magnets were re-shot, twice, and one was checked on Woofer Tester 2 with Grumpy. For all intents and purposes, the T/S parameters matched those for the 2235 and the second time they were shot, the Bl came out a bit above that of spec. I had the magnets reshot because I didn't like the "dullness" of the 2235s and this was to help out..., not that it did. OCS re-shot them at no charge as the Bl was a bit low after the first shot.

  13. #28
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,942
    Given this is an idea for a friend and if you don’t have the drivers or the horn your questions are just tempting conjecture

    Without a working knowledge of the complexities involved it’s guess work.

    Without some real data it’s a guess on what may or may not be a preferred option until such time as you have the horns and some test equipment to measure some approaches to implementing it

    If you are looking for more certainty pre purchase of components other than bouncing off ideas it gets back to following a known design.

    The closest design is the Tad 2 way

    Follow that closely and you will have a higher likelihood of success

    The hypex horn allows good loading down to the desired cross point @650 hertz in a 90x40 angle

    Yuichi points to some of the compromises discussed such as path length delays on his website

    Note the virtual acoustic centre of each driver is seldom the location of the voice cool with the inclusion of the crossover filters

    The phase response includes both the drivers physical and electrical characteristics and the crossover filters electrical characteristics

    Without some advanced test equipment and powerful sumulator like LinearX LMS and LEAP 5 you would find it difficult if not impossible to implement an optimal design

    So what’s the point ?

    That’s why you pay the big bucks for a commercial product

    Some insights

    The 650 Hertz low pass crossover point and a steep crossover point offers several benefits

    Lower vertical nulls or lobbing in the crossover region
    Minimise the impact of cone breakup beyond piston range of the woofer

    Attempting more than a 50mm recess of the woofer is not ideal

    Typically a steep 36 dB crossover may incorporate some acoustic roll off from the woofer and group delay.

    This under simulated conditions provides phase compensation so the crossover transfer function is close to optimal

    The assymetric 12 dB high pass filter in combination with the horns natural high pass function provides the optimal final acoustic Response

    Typically this can be validated by reverse of the driver phase and with fine adjustment a uniform deep null > 20 dB as measured at the crossover is visible

    If you use a digital amp with inbuilt dsp a lot of the hack work problems above can be resolved for the diy builder BUT you still need to be able to measure it properly

  14. #29
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,703
    Quote Originally Posted by Dr.db View Post
    The A-290 is a Hyperbolic-Horn, but there is an Exponential-Horn called A-300 as well.
    How would these differ in sound and which of these is to be favoured?

    I know it´s hard to tell without any measurements, but how big should the offset be between the 2441 driver and 2234 cone with a 12db crossover at ~700hz ?
    @ivica:
    Did you successfully use a l300 crossover with an 2" 2441 driver in the past?
    Did you have to change anything, because this network was initially for the 1"-drivers...?
    ?
    Hi Dr.db,

    Initially I had made no change, but latter, I have reduced 1.55mH to 1mH, and 16uF to 10uF, and have introduced another C round 12uF 'in-series' with 0.3mH as has been in 4345 design. Resistor 7.5 Ohm is put 'in-series' with the mentioned 10uF capacitor.I have sent here its schematics.
    I have done such as 2441(Radian dia)&2311&2308 sounded to me "too agresive".

    regards
    ivica

  15. #30
    Senior Member
    Join Date
    Apr 2014
    Location
    Europa Union
    Posts
    130
    Quote Originally Posted by Dr.db View Post
    I found this picture with google...
    The yuichi horn protrudes a fair bit, would this be ok?
    Would you mount the 15" woofer a bit lower to increase the distance to the horn, or can woofer and horn be mounted closely against each other?

    Name:  yuichi horn..jpg
Views: 1314
Size:  254.1 KB
    Mount the 15" as close to the horn as possible. On Rey Audio Loudspeakers there is 1cm between TL-1601b and RH-3. On Exclusive 2401 and 2402 there was more space between due to the presence of a grid.

    I know (I've seen and heard them twice, the owner is a friend, equiped with JBL 2235H and 2450J) the loudspeakers shown in this picture.
    The horn is a clone of TH-4001 made by ALG Audio in the South of France. ALG is also manufacturing Arai290 horns.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •