BerndH Posted December 20, 2002 Share Posted December 20, 2002 Does anyone knows the power rating of the K 55-M? Is the power rating and the impedance affected by the use of different horns? Why asking? I changed my K-400 mid horn to an EV SM120A mid horn. While i can say after a week of listening there are nearly ten reasons that i like the EV horn over the Klipsch horn, i noticed today a plop from mid driver during listening. I heard the Killing Joke song Turn To Red and when the song starts with strong bass and drum beats i noticed this weird behavior for a only one moment. When repeating the starting passage again at the same spot. It sounded like the mid driver was overdriven. My 2x 75 wpc amp was adjusted at about a quarter of max. Any suggestions are welcome. Bernd Quote Link to comment Share on other sites More sharing options...
TBrennan Posted December 20, 2002 Share Posted December 20, 2002 Bernd---Power handling and impedance are most certainly effected by the horn used. The SM-120s should be loading the drivers properly down to 400hz, or I should say they properly loaded EV 1823 and 1824 drivers down to 400 hz, maybe they're not loading the Klipsch driver as well. The horn might be changing the impedance at 400hz and shifting the crossover point. Or maybe the horns are showing the driver's flaws and not vice-versa. I dunno. I never had a problem with the EVs on the Klipsch drivers and I used to really crank it, like running a Dyna 400 balls out kinda crankin it. www.chicagohornspeakerclub.org Quote Link to comment Share on other sites More sharing options...
BerndH Posted December 21, 2002 Author Share Posted December 21, 2002 Tom, How do you mean a horn has to load a driver? Do you mean the horn has to give a resistance against the membran moving forward? Is the crossover point affect very much or only a few Hz and in what direction - up or down in the frequency spectrum? Thanks for your reply. Bernd Quote Link to comment Share on other sites More sharing options...
TBrennan Posted December 21, 2002 Share Posted December 21, 2002 Berndh---Yes, when the horn is loading the diaphragm it is giving it a resistance of sorts. Use below the point where the horn unloads can cause diaphragm "flutter" and clacking. Crossover point could be changed a great deal depending on actual impedence and the impedence the crossover was designed to see, as much as an octave. Information on how horns effect driver impedence can be found at the JBL Pro and EV websites. I suggest you switch the drivers back to the K-400 horns and see if the problem persists or goes away. I suspect the problem is the drivers themselves as I never had trouble using the EV horns and several people here even report good results using the 500hz Altec 511 horn with a 400hz crossover and I doubt the 511 is working as well at 400hz as the SM-120A is. Quote Link to comment Share on other sites More sharing options...
BerndH Posted December 23, 2002 Author Share Posted December 23, 2002 Tom, I will try your recommended sites. And yes, i followed the post of all the forum members who had tried the Altec 511 horn with great interest. But Altec stuff in Europe is rare and i don't know what my wife is telling me buying horn # 7 + 8 (having already 4 K-400 and 2 EV SM-120A) after i got the EV horns as a Xmas gift from her. LOL. I remembered the described plop when listening with the K-400 horn it sounded similar, but not so strong that i feared i can damage the driver. It is exact the point when the drummer hits the tom but i have no problem with other drum sequences. Maybe its because the EV horn is more detailed in midbass, all songs i played til now i hear much clearer bass. Or it's an effect of all. I like the EV horn so much. I believe it affects even the bass section of the Klipschorn in a good way that you hear the bass notes better playing and jumping in the room - thats what i like a horn for. And the mids are not so screaming while the sweet spot is now very wide. I will leave now my Klipschorn in that configuration. Maybe i change the mid-driver in the future. When i have the chance to get an Altec mid-driver, do you have experiences how it fits mechanically and tonally to the EV horn? Bernd Quote Link to comment Share on other sites More sharing options...
TBrennan Posted December 23, 2002 Share Posted December 23, 2002 Bernd----Yes, the SM-120As are such nice sounding horns. You may indeed simply be hearing things differently now and new things are standing out that didn't before. I don't think there'd be any advantage to using an Altec 1" driver as a midrange device. The Altecs use aluminum diaphragms and are what EV calls "high performence" type drivers. They are meant to be used in 2-ways and to cover both mid and high frequencies. I don't think one would sound any better than the Klipsch driver as a strictly midrange device, the Altec advantage shows best when the driver is used to cover both mids and highs, then you get a wonderfully integrated and natural sound. Also, with it's aluminum diaphragm an Altec driver is not meant to work down to the 400hz crossover that the Klipsch unit works to. 500 is as low as these babies should go. Phenolic diaphragm drivers like the Klipsch mid drivers and the JBL 2470 are noted for good reproduction of midrange and the ability to reach down lower than aluminum drivers. My thoughts and opinions anyway. www.chicagohornspeakerclub.org Quote Link to comment Share on other sites More sharing options...
djk Posted December 23, 2002 Share Posted December 23, 2002 I have a suggestion. Add ONE of the following: A 30 ohm 10W resistor from tap 5 to C A 15 ohm 10W resistor from tap 4 to C An 8 ohm 10W resistor from tap 3 to C And then add 13µF in parallel with the existing 13µF (anything from 10µF~15µF will probably do). The crossover does not work properly unless loaded by its design impedance. Horns have large impedance peaks near their low frequency cut-off. A swamping resistor reduces these peaks. The capacitor value needs to be increased to keep the crossover point the same. Newer networks (AK, AK1, AK2, etc) have bananna plugs that go from the posts on the woofer door up to the top network. Cut these off and replace with pins or spades. Vibration makes these connections intermittent and the midrange can sound 'blown'. Check and see if the plastic back cover on the K55M is glued properly. Quote Link to comment Share on other sites More sharing options...
BerndH Posted January 3, 2003 Author Share Posted January 3, 2003 djk, One resistor should added between the taps of the autotransformer, have i understood right? On my AA network i cannot recognice all the tap labels and i cannot find a usable image or schematic of the autotransformer. What i see is from negative input there goes a wire to the mid tap at the left side of the autotransformer with the label 0, above is a free tap with label 3. The other labels cannot be read. If you have a tap scheme, please send it. The 13 µF capacitor is the big lying capacitor, right? As i have the AA network with oil caps, shall i use another oil cap or can i use any other cap. The back cover is glued properly. What is your opinion about previous posts changing the AA network to a type A network with 6 db/octave slopes? I see it in my special case very critical, or not? Thanks all for their help. Bernd Quote Link to comment Share on other sites More sharing options...
djk Posted January 4, 2003 Share Posted January 4, 2003 How did you end up with a type AA network with a K55M driver? They never came that way. As regards the capacitance in parallel with the existing 13µF, use either film or oil types. As regards the taps on the T2A, the 13µF cap is hooked to #5, the midrange driver is hooked to #4, you found #3, and C=0 As regards the A vs the AA, the woofer to midrange crossover on both is 6dB. The difference is the tweeter section. I don't like any of the Klipsch tweeter crossovers for the Klipschorns. The type A is 6dB/oct and as such has poor power handling and the non-coincident nature of the tweeter and midrange being 18" apart in different planes causes a series of peaks and dips spanning two octaves centered at the crossover frequency. The type AA is a Chebychev, by design they 'ring'. The type AK and newer are Cauer, or elliptical filters. The un-damped pole at 5Khz rings like mad on female vocals. I think the ALK crossover with its maximally flat Butterworth filter to be a better solution. A Bessel filter has the best transient response, and simply adding a 30R/2W resistor in parallel with the tweeter with the ALK network makes the Q droop a bit and come closer to a Bessel. $15 will buy the parts for a pair from Madisound: (2) each 2.2µF, 6.8µF polypropylene caps by Bennic, 0.20mH small bobbin air core, and Eagle resistors. If anyone owns the ALK network I would suggest you try the resistor. If you don't care for it you are out about $1. Quote Link to comment Share on other sites More sharing options...
BerndH Posted January 5, 2003 Author Share Posted January 5, 2003 djk, The K-55 M drivers were replaced by myself for the older K-55 V and a Cervin Vega driver, which was inserted by the former owner. The CV driver didn't match, because the midbass response was too weak. So i bought a pair of the newer M-type drivers. When i would use the ALK crossover, it is wise to add your recommended impedance filter network in it? Bernd Quote Link to comment Share on other sites More sharing options...
djk Posted January 6, 2003 Share Posted January 6, 2003 The Cerwin Vega driver is an Atlas PD4, the Klipsch is an Atlas PD5. While they look similar on the outside there are big differences inside. If you are constructing an ALK filter for yourself try adding a 30R/2W resistor in parallel with the tweeter. He already has a resistor in parallel with the midrange. Again, I would encourage you to spend $20 or so modifying the AA first. Quote Link to comment Share on other sites More sharing options...
djk Posted January 6, 2003 Share Posted January 6, 2003 The Cerwin Vega driver is an Atlas PD4, the Klipsch is an Atlas PD5. While they look similar on the outside there are big differences inside. If you are constructing an ALK filter for yourself try adding a 30R/2W resistor in parallel with the tweeter. He already has a resistor in parallel with the midrange. Again, I would encourage you to spend $20 or so modifying the AA first. Quote Link to comment Share on other sites More sharing options...
BerndH Posted January 8, 2003 Author Share Posted January 8, 2003 I think it is a Cervin Vega driver. I fetched the driver and his label is Vega Power VP-100D, 8 Ohm 60 Watt, Taiwan. I added a picture where you can see it. It is the bigger driver, the smaller is the K-55 V. The horns are K-400 clones or prototypes, which i bought with the K-55 M drivers. I never used them. I always used the original K-400 horns with the PWK-logo, now i have the EV-horns. I can swrew the Vega driver in the K-400 horn without adaptor. I found the Vega has less mid-bass. I would say he is really usable above 600 or 800 Hz. And he is a little bit more quiet than the K-55 driver. Perhaps it seems because it is an 8 Ohm driver. Bernd Quote Link to comment Share on other sites More sharing options...
BerndH Posted January 8, 2003 Author Share Posted January 8, 2003 djk, Today i ran my test CD over my Klipschorn with the EV horns. I created in Cool Edit software test tones starting with 30 Hz, then 35-40-50-60-80-90-100-110-120-150-180-200-250-350-450-450-500-1000 and so on in wider steps to 20 kHz. But in the named frequencies i tested the transition from bass to mid-horn. I can only use my ears, i have no testing equipment. I left all speakers connected and took my ears right in front of the mid-horn. I meant to listen that the frequencies up from about 150 Hz come already out of the mid-horn (and bass-horn). What do you think about? Can this be overtones/harmonics from the base tone, can the crossover point have really moved to lower frequencies after changing the mid-horn or is this simply regular that this low tones pass the crossover to the mid-driver? I'm sorry i didn't add until today your impedance filter. If the crossover point really have moved, does your filter network correct the crossover point to the original value? Really sorry i didn't add now your filter network. Maybe then i don't have to ask. Thanks for your reply. Bernd Quote Link to comment Share on other sites More sharing options...
BerndH Posted January 10, 2003 Author Share Posted January 10, 2003 djk, Yesterday i bought the parts and applied them this morning before work to the right channel speaker crossover. A serial connection of a 4,7 Ohm and a 3,3 Ohm ceramic resistor from tap 3 to C. A parallel connection of a MKT 5% 10 µf and 3,3 µF in parallel to the big lying capacitor, which i assume is the 13 µF capacitor cause the two standing caps are labelled 2 µF. Please note i have the AA network. I hope and think i have done right. After a quick comparison it seems the filter will work well. The right channel sounds cleaner and bass, mids and highs sound more integrated and harmonic. It's difficult to describe, but the modified speaker seems the better. When i have break at midday, i modify my left channel crossover. Bernd Quote Link to comment Share on other sites More sharing options...
Frank Jansz Posted August 1, 2020 Share Posted August 1, 2020 On 1/10/2003 at 2:12 PM, BerndH said: djk, Yesterday i bought the parts and applied them this morning before work to the right channel speaker crossover. A serial connection of a 4,7 Ohm and a 3,3 Ohm ceramic resistor from tap 3 to C. A parallel connection of a MKT 5% 10 µf and 3,3 µF in parallel to the big lying capacitor, which i assume is the 13 µF capacitor cause the two standing caps are labelled 2 µF. Please note i have the AA network. I hope and think i have done right. After a quick comparison it seems the filter will work well. The right channel sounds cleaner and bass, mids and highs sound more integrated and harmonic. It's difficult to describe, but the modified speaker seems the better. When i have break at midday, i modify my left channel crossover. Bernd I need to know at what impedience is the Klipsch K 55 V Driver is it 16 Ohms or is it ,8 Ohms Rated Please inform me. RGDS Francis Jansz Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.