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Help me convert old speakers to actives

Some estimates of what bass extension can be expected -

Assuming a 3mm to 4mm max excursion (which I believe is rather generous for these drivers) at 90dB to 96dB at 1m the theoretical LF extension is in the 50-90Hz range.
 

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I hear (source: Hypex) Hypex is planning to update their Fusion amps to NcoreX next year. I am guessing here, but chances are they may update not just the amp tech but also something in the DSP part and maybe some other functionality. Would be nice to have wireless input e.g. Airplay2, Bluetooth, WISA.
 
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Looking at audio interfaces and mics:

Can someone recommend a pair of an interface and a mic?

I was looking at e.g. Focusrite Scarlett 2i2, but there is 3rd gen and 4th gen. Is there any difference apart from location of inputs?

And what is a decent mic?

If the pair will cost similar to Umik2, I would go for xlr and interface (to avoid the time reference issue).
 
Looking at audio interfaces and mics:

Can someone recommend a pair of an interface and a mic?

I was looking at e.g. Focusrite Scarlett 2i2, but there is 3rd gen and 4th gen. Is there any difference apart from location of inputs?

And what is a decent mic?

If the pair will cost similar to Umik2, I would go for xlr and interface (to avoid the time reference issue).

What interface you get depends on your needs. More expensive interfaces have:

- More DAC channels (2i2 only has 2)
- More digital inputs (2i2 only has USB)
- Expandability via AVB, Dante, Ravenna. You can group multiple devices together.
- Sometimes expandability through option cards, e.g. Merging interfaces
- Advanced routing options, you can route any input to any output, you can loopback, etc.
- Mixer software. RME has Totalmix, Merging has Pyramix. Not sure if the 2i2 even comes with it.

Decide what you need and choose an interface. If you don't need any of that advanced stuff, the 2i2 is perfectly fine.
 
As for measurement microphone(s), if you would like to have industry-standard ones with each calibration data, I recommend you to consider getting EARTHWOKS AUDIO microphones; they are rather expensive, though.

For your home use, I believe M23 (flat upto 23 kHz) or M30 (flat upto 30 kHz) would be more than enough.

I have been using affordable BEHRINGER ECM8000 with no calibration data attached, but very fortunately my specially selected ECM8000 is still flat within 1.2 dB range (+0.7 dB, -0.5 dB) over 10 Hz - 21 kHz. I could cross calibrate my ECM8000 in reference to expensive calibrated EARTHWORKS M50 which my friend is using (ref. here on my project thread).
 
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As for measurement microphone(s), if you would like to have industry-standard ones with each calibration data, I recommend you to consider getting EARTHWOKS AUDIO microphones; they are rather expensive, though.

For your home use, I believe M23 (flat upto 23 kHz) or M30 (flat upto 30 kHz) would be more than enough.

I have been using affordable BEHRINGER ECM8000 without calibration data, but very fortunately my specially selected ECM8000 is still flat within 1.2 dB range (+0.7 dB, -0.5 dB) over 10 Hz - 21 kHz. I could cross calibrate my ECM8000 in reference to expensive calibrated EARTHWORKS M50 which my friend using (ref. here on my project thread).
I use a Behringer ECM8000 which I calibrated against a calibrated Earthworks mic, so OK for my needs.

S
 
I use a Behringer ECM8000 which I calibrated against a calibrated Earthworks mic, so OK for my needs.

S

Very nice to hear you too did exactly the same cross-calibration of your ECM8000 against Earthworks mic like I did last year!:)
 
A bit of a stumbling block - Hypex Filter Design software is Windows only and I do not have a Windows computer. Also trying to source a second-hand audio interface and a mic.

In the meantime I am thinking to do a simpler and cheaper project - a sub to add to the kitchen speakers
 
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The kitchen system is a pair of Genelec 6010a fed from Airport Express via Genelec volume control. The speakers are mounted at the top of the kitchen wall units.
I was thinking to use a long plastic pipe with a basic driver at each end and power it by a small/cheap subwoofer amp.


Untitled by AlmaAtaKZ, on Flickr

So the sub will have to work from about 80Hz to as low as feasible, say, 30Hz and low to medium SPL.

Before any calculations, the pipe could be be 1m-1.5m long, 150 to 200mm diameter, drivers of max size to fit the pipe ends.

Amp could be this one:



I think if I get 8ohm drivers I can connect them to the amp in parallel and it will drive them OK, but I am not sure how to check this. The amp spec does mention 4ohm.

I have no idea what I am doing - struggling to calculate the required volume for the enclosure. Do I just double the volume for 2 drivers vs 1? When I try to calculate the volume here, it is asking me for 'actual system Qtc', which does not seem to be on driver datasheets. Where do I get this parameter? Or do I set it as a design objective?

 
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A bit of a stumbling block - Hypex Filter Design software is Windows only and I do not have a Windows computer. Also trying to source a second-hand audio interface and a mic.
You can use a virtual machine with USB passthrough and a Windows developer image (free, time limited). I did this with VirtualBox on linux, passing the Hypex USB connection through to the Windows virtual machine. You may also need to pass the audio interface connection through.
 
Maybe WINE can be sufficient for this.
 
Maybe WINE can be sufficient for this.
Assuming you're talking about running the Hypex software on something other than Windows, the answer is no. At least it was when I tried it - I haven't tried it for a year or two, and there has been a major version upgrade since then. The software includes the driver used to communicate with the DSP, and that doesn't work in WINE.
 
WINE provides a lot of DLL and that stuff to run Win programs in Linux, but if that does not succeed the mentioned VM including passthrough should work flawlessly.
 
I'm assuming you're thinking of a DSP-based crossover, not an analogue crossover made with op-amps. The benefits of a fully adjustable DSP-based crossover are just too great to contemplate analogue.
My experience quite the opposite. Loved feature set of the DCX2496, really wanted to make it work but in the end the sound of the unit was not nearly as good as an analog unit. In my experience a good active analog crossover wins the sound comparison easily. Ease of use and feature set - DSP based wins but that's not enough for me.
 
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