Hello everyone. Been lurking for quite a while, decided on most things, need advice.
Midwoofer: 2x Faital Pro 10RS350 in D'Appolito config
Tweeter: Faital Pro HF10AK or HF108 (can get the latter real cheap) coupled to B&C ME45 horn
Box: 30mm plywood, Vb=60L, ported, Fb=35-40hz
Crossover: 3rd-4th acoustical at 1300-1500hz (I am lucky to have a friend who uses an active crossover for his speakers, going to visit him with mine and play with the tuning before making a passive)
The biggest concern for me was finding a 10 inch midwoofer (not willing to go any smaller) that wouldn't break up until 2khz and had Fs<45hz. I think the Faitals would do the job pretty well and I can get all four for less than $450, but I'm open to other suggestions in the same price range.
Also, is it a good idea to calculate the passive crossover based on the parameters calculated with my friend's active one?
Current speaker box made in Speakerboxlite looks like this. The horn will be located between two midwoofers.
Thoughts?
Midwoofer: 2x Faital Pro 10RS350 in D'Appolito config
Tweeter: Faital Pro HF10AK or HF108 (can get the latter real cheap) coupled to B&C ME45 horn
Box: 30mm plywood, Vb=60L, ported, Fb=35-40hz
Crossover: 3rd-4th acoustical at 1300-1500hz (I am lucky to have a friend who uses an active crossover for his speakers, going to visit him with mine and play with the tuning before making a passive)
The biggest concern for me was finding a 10 inch midwoofer (not willing to go any smaller) that wouldn't break up until 2khz and had Fs<45hz. I think the Faitals would do the job pretty well and I can get all four for less than $450, but I'm open to other suggestions in the same price range.
Also, is it a good idea to calculate the passive crossover based on the parameters calculated with my friend's active one?
Current speaker box made in Speakerboxlite looks like this. The horn will be located between two midwoofers.
Thoughts?
Attachments
Well............
That is a big mtm.
The sit / stand test may not be the same until you are 12' away.
But people have loved the klipsch epic (10" or even a 12" mtm), so there is that.
That is a big mtm.
The sit / stand test may not be the same until you are 12' away.
But people have loved the klipsch epic (10" or even a 12" mtm), so there is that.
Epics were my main inspiration for the project. I think they are badass.
I'd get 12 inch woofers like in CF4 but I highly doubt their ability to do midrange (unless with a 2" tweeter crossed at 1khz? But then the top octave would fall off a cliff)
By that you mean the tweeter having to be at ear level right?
For best results if you find a response you'd like to aim for, you should measure the electrical response at your friends place to use in making the passive. You could do it using just the parameters if that's all you can get.
There should be some flat measuring 12's that will need zobel for passive crossover.
I recommend the emenence delta pro 12a.
Yes it climbs a little, but not huge spike break up past 800hz either.
Yeam 10 should be fine.
I recommend the emenence delta pro 12a.
Yes it climbs a little, but not huge spike break up past 800hz either.
Yeam 10 should be fine.
I think the sit/stand situation mentioned is that with the woofers that far from each other, and the crossover point a horn of only that size will limit to be high in frequency, the nulls from the woofers interracting could be pretty close together --- stand up and you will be in a null if you are very close.
I'm planning to play around with various filters, xo frequency and find out the needed attenuation for tweeter resistors. Is that enough?
I guess I can just base impedance off datasheets right?
Oh, so it was about the woofer cancellation...
I read that the distance between woofers should be equal to xo freq wavelength, which I can meet with 343/1500=0.23m. I'll need to adjust box dimensions for the best visual look though.
I took a look at the Eminence suggested and I don't think I really need that extra SPL from 12 inches and it definitely won't give me extra depth due to high Fs. I guess I'll stick with the Faitals.
Also, I can only get 8 ohm Faitals cheap. Is it better to wire them in series or in parallel? If there were 4 ohm ones in stock it'd be obvious, but there aren't any sadly.
I assume you only have some time to be reconfiguring your friends DSP with your speakers. Normally it would take longer but if you prepare you can get value for the effort.
Before you start, choose your crossover frequencies, understand where your woofers break-up and where you can run them to and how steep to cut them. This will help you save time.
Put your speakers in a similar position in the room (compared to your room) and experiment with this. Set some filters. Repeat. If you are lucky you will find something that sounds OK. If you can take a measurement about 1m in front of the speaker you can see (basically) whether they blend. Measuring the drivers separately can increase the confidence there a little.
It's important that at the end of your session you have the required EQ for each driver. You can use this in a simulator with a trace of the impedance from the datasheet, as you say.
BTW, an MTM can be configured in more than one way. I guess you would find your starting point now, but continue with your research.
Before you start, choose your crossover frequencies, understand where your woofers break-up and where you can run them to and how steep to cut them. This will help you save time.
Put your speakers in a similar position in the room (compared to your room) and experiment with this. Set some filters. Repeat. If you are lucky you will find something that sounds OK. If you can take a measurement about 1m in front of the speaker you can see (basically) whether they blend. Measuring the drivers separately can increase the confidence there a little.
It's important that at the end of your session you have the required EQ for each driver. You can use this in a simulator with a trace of the impedance from the datasheet, as you say.
BTW, an MTM can be configured in more than one way. I guess you would find your starting point now, but continue with your research.
Don't forget about the Exclusive S5
EXCLUSIVE S5
Allens' advice on doing thorough research on this design is spot on. The integration with the horn/driver is going to make or break your effort. Your cabinetmaking skills have to be up to the task as well. I see many rounded or large chamfers in your future 🙂
Is your friends active XO "state variable" or full blown linear phase DSP? I ask because designing a passive XO using say a full DSP as a blueprint may not yield best results, only because you may not be able to duplicate that solution "passively". If you're set on a passive solution, may be best to follow those traditional design frameworks?
EXCLUSIVE S5
Allens' advice on doing thorough research on this design is spot on. The integration with the horn/driver is going to make or break your effort. Your cabinetmaking skills have to be up to the task as well. I see many rounded or large chamfers in your future 🙂
Is your friends active XO "state variable" or full blown linear phase DSP? I ask because designing a passive XO using say a full DSP as a blueprint may not yield best results, only because you may not be able to duplicate that solution "passively". If you're set on a passive solution, may be best to follow those traditional design frameworks?
Judging by the on- and 45° off-axis FR, the woofer only starts to break up at about 3khz. Minimum recommended tweeter cutoff is 1300 hz using at least 2nd order. I think 1300-1500hz with 3rd-4th order acoustical will make a good xo point.
Also we're planning to measure the speaker outside as a substitute for anechoic chamber. He told me that he uses an active xo in his car too so we'll work with that.
Nice speakers, altho not quite as cool looking as Klipsch Epic.
I'll trust furniture makers with laser cutting the speaker box walls. The only problem is that >18mm thick MDF/plywood seems scarce, maybe I'll have to make my box a bit thinner.
Both of my friend's xo's are full DSP, but I guess the difference between DSPs and passives is mainly in inability to adjust phase delay and switch filter types on the fly. Am I wrong?
If they are linear phase you have an ability, through certain EQ combinations and XO points, to dial in a near perfect XO response. It's a little more than just changing filter types/positions. Some DSP's have a software simulator to help manipulate xo points and eq (rates and bandwidth) to better understand the relation to phase. This can get you close and then verify with real physical measurements.
The level of accuracy then achieved by the DSP might be difficult to duplicate with passive components. ... borrow your friends DSP and forget to return it? 😛
The level of accuracy then achieved by the DSP might be difficult to duplicate with passive components. ... borrow your friends DSP and forget to return it? 😛
This has something to do with phase response I guess? Gotta refresh my control theory knowledge from uni.
Not willing to go active mainly because I'd need a second 2ch amp and a DSP which is a little out of my budget. I'll already be broke af when I get the drivers lol. Student life...
Hi,
do you have a computer with multiple out soundcard? If so you don't need a hardware dsp processor.
That said it'll depend of your source. If you have something like tapeplayer or TT it may be a compromise. Otherwise if source are mainly digital you'll only need a second stereo amplifier.
Nah, I don't have a soundcard but a DAC/HPA which only has a single pre out. Also I don't really want to pile up gear so I'd prefer to go passive.
After some googling I think I got it. If I want near-DSP filtering quality I'll either have to use LR4 which has a phase shift of 360 or set up Zobel in order to flatten the frequency-dependent impedance so that there is no phase shift.
Is everything correct?
Is everything correct?
Found this: Beyma 12BR70
93db @ 1W
Fs=31
Qts=0.5
Le=0.85
+/-3db flat up to about 2.5khz
And it costs 30 bucks less than a 10RS350.
Wow, RIP Faitals. I can even go for a sealed box with Beymas but I'll probably still go for a huge ported one. They won't do midrange as well but I can trade that for 20hz deeper bass.
93db @ 1W
Fs=31
Qts=0.5
Le=0.85
+/-3db flat up to about 2.5khz
And it costs 30 bucks less than a 10RS350.
Wow, RIP Faitals. I can even go for a sealed box with Beymas but I'll probably still go for a huge ported one. They won't do midrange as well but I can trade that for 20hz deeper bass.
I know you're tight on cash but you do have to factor in passive component costs vs say a miniDSP and an additional amp. I think you'd be ahead with the active choice $wise.
Good thinking. Try to get the larger breakup region down far enough.
Linear phase might used for a couple of reasons but I don't think it is normally necessary.
I have never had this problem, although I agree that there is some learning to do before you can get the best results.