I’m sure this isn’t new but,
I want to experience an active system utilizing as much of the gear I already have as possible. I’ve got 3way hybrid speakers. The woofer is in a ported box with mid and tweeter on open baffle ( Dick Olsher designed Basszilla). I also have a Marantz Sr 7300 receiver (6 discrete channels). Why not add a MiniDSP and disconnect the passive networks and resupply the speakers directly from the dsp.
Bad idea? Doable? Ridiculous?
I do have additional amps that could be used, a Pass F6, and a pair of 300b monoblocks.
I want to experience an active system utilizing as much of the gear I already have as possible. I’ve got 3way hybrid speakers. The woofer is in a ported box with mid and tweeter on open baffle ( Dick Olsher designed Basszilla). I also have a Marantz Sr 7300 receiver (6 discrete channels). Why not add a MiniDSP and disconnect the passive networks and resupply the speakers directly from the dsp.
Bad idea? Doable? Ridiculous?
I do have additional amps that could be used, a Pass F6, and a pair of 300b monoblocks.
Try, but keep your passive X-overs, in case you change your mind after a while.
This suggestion should be the starting point to your project. You will need both the electrical drive signal frequency response and the acoustical frequency response for each driver (including the passive filter). You will also need the frequency response of the system as a whole. Only with all this data will you be certain you have replicated the passive filter performance, and accounted for the differing gain of each amp, and any time delays.
After you replicate the passive filter performance, you can begin experimenting with the full potential of active filter networks.
No,
it can not been said often enough, measuring comes before anything else.
Maybe this will not be what you want to hear, but forget anything about amps, DSP and what ever gear until you have a measuring system and know how to use it.
If you do not have a microphone with a matching preamp (audio interface), this will cost you less than 100$ new on entry level. Usually an electret mic and a 48V phantom power pre. Most measurements you do will be for comparison, so the absolute precision is not really important. If, later your expectations rise, you may get mike and amp calibrated. spending a little more on the interface will save you days of frustration, I can recommand Focusrite products, better buy a good one used than new low quality stuff. If drivers do not work perfectly, you won't get happy.
If your speakers are satisfying to you, measure them in a room at a fixed position. As you do not have an anechonic chamber, this is your reference line. In the process of learning your measuring program (REW or Arta are free and most used), you will see if these in room measurements make any sense. Maybe compare to manufacturers and review data. If you think the recorded data fit somehow to your room and speaker situation, go on.
Now take the x-over to the outside and separate it. Any way should works for it self, independent of the other drivers.
That way you can measure each single driver as it works passive on your speakers volume and baffle.
Store all these measurements with clear description/ name, so you can find them to compare. Remember, do not change the room or speaker position even a little, as the room is part of the measurement.
At this point you can still use your speaker if you reconnect the inputs of all drivers. Only difference, you have the x-over on the outside, something that high end people prefer anyway.
You should be able to add low, mid and high measurements to a curve that exactly matches the recorded overall response of the speaker you did in your room. A valuable test for your test set-up.
Usually anything lower than 200-400Hz is of limited interest. Better measure the TSP of the woofer and do a simulation of it's response.
Then you should find out how to measure the electrical response of your drivers. This information will help you to rebuild the passive x-over components in your DSP.
Finally, this is the point where you may start to set up your active gear. You should not connect your “good” drivers to it until you have verified anything to work without any fault. A few very cheap speakers come handy for this dangerous test driving...
it can not been said often enough, measuring comes before anything else.
Maybe this will not be what you want to hear, but forget anything about amps, DSP and what ever gear until you have a measuring system and know how to use it.
If you do not have a microphone with a matching preamp (audio interface), this will cost you less than 100$ new on entry level. Usually an electret mic and a 48V phantom power pre. Most measurements you do will be for comparison, so the absolute precision is not really important. If, later your expectations rise, you may get mike and amp calibrated. spending a little more on the interface will save you days of frustration, I can recommand Focusrite products, better buy a good one used than new low quality stuff. If drivers do not work perfectly, you won't get happy.
If your speakers are satisfying to you, measure them in a room at a fixed position. As you do not have an anechonic chamber, this is your reference line. In the process of learning your measuring program (REW or Arta are free and most used), you will see if these in room measurements make any sense. Maybe compare to manufacturers and review data. If you think the recorded data fit somehow to your room and speaker situation, go on.
Now take the x-over to the outside and separate it. Any way should works for it self, independent of the other drivers.
That way you can measure each single driver as it works passive on your speakers volume and baffle.
Store all these measurements with clear description/ name, so you can find them to compare. Remember, do not change the room or speaker position even a little, as the room is part of the measurement.
At this point you can still use your speaker if you reconnect the inputs of all drivers. Only difference, you have the x-over on the outside, something that high end people prefer anyway.
You should be able to add low, mid and high measurements to a curve that exactly matches the recorded overall response of the speaker you did in your room. A valuable test for your test set-up.
Usually anything lower than 200-400Hz is of limited interest. Better measure the TSP of the woofer and do a simulation of it's response.
Then you should find out how to measure the electrical response of your drivers. This information will help you to rebuild the passive x-over components in your DSP.
Finally, this is the point where you may start to set up your active gear. You should not connect your “good” drivers to it until you have verified anything to work without any fault. A few very cheap speakers come handy for this dangerous test driving...
If OP is satisfied with the speakers currently, and wants only to duplicate that, then it is best to avoid using a microphone in the process. It isn't necessary and would only add a means of introducing errors.
First, I’m grateful for all the interest and support from this group.
Allen,
I’m not really satisfied with my speakers currently. I just spent 20 minutes writing a response and then deleted it. The bottom line is I’m chasing sound quality in a less than ideal room. Dsp seems a logical path to investigate. I’m learning slowly but it’s complicated by budget. So diy has become my savior so to say. Again I very much appreciate support from this group
I hope everyone reading along has a safe and healthy holiday
Turbo,
I will have to read your post though again to understand it all but do appreciate your help. I’m trying to get up to speed on a dsp based system and going fully active. Chasing sound quality.
Best
IME helping amateur 'garage' bands way back when, this can't be emphasized enough!
You could also look at analog active crossovers. There are many to choose from including DIY kits designed by Nelson Pass.
In recent years I've used an ART CX310 and CX311 on two systems and I'm quite pleased with the results.
They are fairly easy to setup and adjustments can be made in real time, as you listen.
Measurement tools like REW are certainly helpful, but not required.
Sorry, I don't have experience with DSP (yet) for comparison, but I am interested in how it works out for you.
For me, going active made a very noticeable increase in clarity and detail across the entire audio spectrum. With quality recordings, it's simply startling how real it can sound. Best of success!
A crossover begins with the acoustic conditions. This one is somewhat unique and maybe not too simple. Your room is going to be involved in the result. Do you find the open mid has the ability to blend?
I actually have that Pass diy analog crossover on my bench waiting on parts. I will probably invest in a mic and use REW or similar to measure. An “ increase in clarity and detail “ is really what I’ve been after for a long time. I will try and keep this thread updated
Best
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The first thing would be having the tone of the direct sound match to the tone of the room contribution. This is part of the underlying character of a speaker. The delay of the mid reflections are also going to have temporal effects as well as possible resonances.
All these things are going to challenge your crossing, and some may not have absolute solutions.
All these things are going to challenge your crossing, and some may not have absolute solutions.