An additional possibility (if you're just doing rough tests) is that the compression drivers can accidentally be much louder than the other driver(s). At least, I've found it hard to judge them without measurements, especially if their uncorrected frequency response isn't flat.
This is a measurement that someone made on a German Speakerforum with a BMS 4594 on a B&C ME90 horn:
https://i.ibb.co/b1V7bMB/Messung-FR07.png
I would say that it looks quite good. Not perfect but EQable to a nice response. But have a closer look at the almost non-existing overlap ! This means designing a crossover for it is not an easy task. A "textbook crossover" will definitely not work.
Regards
Charles
P.S.: The very extensive driver and horn measurement series the above graph came from is this one here: https://www.lautsprecherforum.eu/viewtopic.php?t=8073
Thank you Zeci !
https://i.ibb.co/b1V7bMB/Messung-FR07.png
I would say that it looks quite good. Not perfect but EQable to a nice response. But have a closer look at the almost non-existing overlap ! This means designing a crossover for it is not an easy task. A "textbook crossover" will definitely not work.
Regards
Charles
P.S.: The very extensive driver and horn measurement series the above graph came from is this one here: https://www.lautsprecherforum.eu/viewtopic.php?t=8073
Thank you Zeci !
Exit angle of driver not compatible with horn throat angle?
Slight mismatch in position of driver exit and horn throat can also give this.
Not exactly the same CD, but everything I've read says the 4594HE is all but the same as the regular 4594, other than a phase plug.
Plus they both take the same BMS passive crossover. (which i don't use)
I cross at 6300Hz. And delay the upper section 0.08ms. Inverting the upper section if using a fully complementary xover type.
Those settings have worked on at least 8 commercial horns, and i don't know how many DIY conical unity/synergy's.
I've never found closely matching the CD to horn or exit angles (as long as they don't contract) to make all that much of a sonic difference, after EQing which i believe is the only valid way to assess comparisons
Horn pattern differences are the biggie, ime. I really question meticulous mating's effect ....
(Maybe I'm just deaf...my hearing rolls off above 14k.)
So, I'd say try the above settings with your miniDSP. EQ the two CD sections.
Measure to set relative levels and verify polarities,
both between the CD's sections, and with the rest of your speaker.
Good luck !
Thanks for the advice all. I've got a Dayton Audio Active Crossover coming to try out. The MiniDSP Flex I just can't get the settings to work. I crossed over at 7000 and just sounds horrible. Even bought another more entry level compression driver and it also sounded horrible. I'm beginning to think it's a faulty MiniDSP Flex.
I reckon a good way to test this would be to just try it as a DAC/preamp for a pair of passive speakers. If the sound is still horrible, maybe it is the flex unit.
I’m super new to the hobby so still learning… I had turned off PEQ and FIP on the MiniDSP and was trying to just start with raw crossover settings:
Attachments
I had the gains set to -20, then tried up to -11. -20 sounded better- but still like it was coming out of a tin can.
I think also I’m so new at this that I’m not understanding everything yet.
Thanks for everyone’s help and patience with me.
I think also I’m so new at this that I’m not understanding everything yet.
Thanks for everyone’s help and patience with me.
If you are setting the standard fixed crossovers which have equal and opposite slopes for each side, you are not giving yourself any control over the natural variations between sides, nor their own unevenness. They don't start out as flat lines on a plot.
Eg: the tweeter might start out louder than the mid. Maybe the mid has an upward tilt in its response. Then there's the resonances for the parametric EQ you mention.
While it's usual to measure these, you could at least guess for now. Does you EQ allow you to make global adjustments? Can you do tilt? Shelving?
Eg: the tweeter might start out louder than the mid. Maybe the mid has an upward tilt in its response. Then there's the resonances for the parametric EQ you mention.
While it's usual to measure these, you could at least guess for now. Does you EQ allow you to make global adjustments? Can you do tilt? Shelving?
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Have you performed actual measurements? And then created crossovers based on said measurements?
Not yet. I finally have a UMIK1 and I’m trying to figure out exactly how to use REW.
Sorry I hit you with info earlier that probably sounded like greek ....didn't realize where you were in the learning stage.
Like everyone is saying, by all means get to where you can measure and set levels first. Then everything will incrementally start making sense.
Oh, I'd I strongly advise not to form any opinions or get discouraged by what you hear, until you can get levels right between the CD sections, and between rest of speaker. Then you can begin to EQ sections and play with xover.
Start by turning down the compression drive level in miniDSP. Turn it down until it starts sounding like music. Easy. You might need 10-20 db of lower level for the CD before it comes into normal territory. At least this will help you get closer to what you need and you can enjoy some sound. Then keep learning about crossovers, EQ etc.
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Can't expect anything to sound like music before proper measurements and crossover simulations are done. Anything else is shooting blindly
Okay, but that is not very helpful to the person above seeking help. Getiing little successes helps keep the motivation.
Is anyone using compensation on their CD / horn combinations? I use a resistor in parallel with an inductor going to the compression driver to give 12db of boost to the highest frequencies. (to be technically correct, cutting the lower frequencies) I'm not at home right now, but I think that it is an 8 ohm resistor in parallel with a 7 mh inductor, going to an 8 ohm compression driver. The CDs that I use are an Altec 902, Selenium 220 with Zilch designed correction network, and Celestion 1746 (1745?). Horns are Edgar salad bowl, B-52 from PE, and Dayton copy of JBL, also from PE.