Hey Hemi, my experience with all but the very latest adda conversion is it gets pretty bad pretty quick after more than two conversation cycles. Those on the minidsp are not even as good as the dcx. I will only use the dcx with digital input. I would have to enter the minidsp analog. Its o ly 48k sampling and marginal converter chips. Better off very high end dsp or staying all analog.
If I could enter digitally all the time, I would consider the hddsp unit, but now its expensive. I would almost guarantee the little 35$ analog unit would sound worlds better based on its topology, unless I missed something truly fundamental. The specs and parts suggest a fine unit. Unless I missed......
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I see low end peq limit is 150, but I will assume the out bands are shelving, which would likely be fine.
Yep, I am aware. I cap bypassed mine. Still was not happy with the adda. Didnt like the original minidsp either. Lost transparency. No wine tasting here it really did.
Yep, I am aware. I cap bypassed mine. Still was not happy with the adda. Didnt like the original minidsp either. Lost transparency. No wine tasting here it really did.
Hey guys, one more very important thing. This is wired series parallel to 4 ohms. Let's assume a lower than I will use crrossover point of 150 hz, 12 db per octave. I have 9 3fe35's per box, please help me calculate the amp power I need to drive these things to maximum safe level above 150 with headroom. I will be using around 200 hz at 18db per to "sub woofer" in reality, but could you guys help me get a "feel" for power? And what do guys calculate the efficiency at now? Thanks again all, the response I got from people at my gig at Casino pool was tremendous but I was using a heavy Carver power amp.Going to class D light. What do you guys think we need?
89-90dB + 3dB for each doubling of speakers, plus a little extra for the 9th, so it's probably about 99dB/watt @ 1m.
But WinISD says 94dB/watt @ 1m! So it comes down to: do you believe WinISD's predictions or Faital's published plots? Maybe call it 96.5dB/watt @ 1m as a compromise.
WinISD says it'll reach 120dB @ 1m with 400w input, Faital says 125dB. 400 for midtops should be fine though, as the music signal up there is much less strong than the bass signal in most music program anyway. 400 is also a reasonable sub input to get a similar response out of a reasonably efficient sub, so something in the 2x350-2x500w range in the amp would be appropriate.
There are loads of options for class D amps, depends how DIY you're comfortable with going, how much you want to spend, and how reliable you want it to be. Sure Electronics do some pretty amazingly cheap class D chip amps with a DC voltage input. You could purchase 2x600w amps based on Texas Instruments TAS5601 (or similar, TAS56something) chips, plus a PSU/PSUs to power them for something in the region of $150 all in, and it would all come in at around 2kg total. But their QC is not the best in the world and there have been incidents reported on DiyAudio of the amps turning up and having a fault that's not immediately apparent impacting sound quality, that then needs fixing.
Being a chip amp you'd obviously need to be very careful not to slip and fry anything in set-up and assembly as well. I lost more than a couple of Class D boards like that.
So you get what you pay for, more or less, but you get a LOT for the money from Sure Electronics, and I'm overplaying the risk factor a little bit as a warning, but it shouldn't go un-noted. If you're still planning to cut sheet metal as part of your designs then you should be able to cut a neat backplate, buy a few off-the-shelf LEDs and switches, and set it up to look quite professional.
The other advantage with the Sure amps, if it's of any use to you, is you can run them from an array of 12v batteries (3 wired up in series for 36v) and take the system off-grid for times when generator or grid access is unavailable.
Actually, I just noticed that the Faital's in an array of 9 actually don't like a 400w input much at all. They're 3.6mm excursion at 200Hz, and I don't think they like more than 1.75mm (and you don't ideally want to be running your mids and highs on an woofer that's gone even close to it's xmax if you can help it).
If I were you, I would seriously consider running your crossover higher when you need high output, and run it lower only when playing lower output or inside rooms with appropriate acoustics. If you run the tops from 300Hz, the excursion with 400w of input is 1.68mm. If you have some headroom in your amp then you can safely/musically boost them by 3dB or more at frequencies from 400Hz and up.
You might be able to get away with a single Sure TAS5601 amp, with 2x300w, which you could probably pick up with a PSU for less than $80 - I haven't checked prices recently. Being able to put 600w into a sub would be optimal though, especially if it's lower efficiency than the tops.
Edit: Be careful to check impedances with amps and drivers obviously. Your 9 driver array presents some weird impedance issues surely? How are you wiring it currently?
The Sure amps are made in China but I think Partsexpress stocks them for a relatively modest markup so you can get them quickly enough in the US (and probably enhanced support for if something goes wrong if you go PE)
But WinISD says 94dB/watt @ 1m! So it comes down to: do you believe WinISD's predictions or Faital's published plots? Maybe call it 96.5dB/watt @ 1m as a compromise.
WinISD says it'll reach 120dB @ 1m with 400w input, Faital says 125dB. 400 for midtops should be fine though, as the music signal up there is much less strong than the bass signal in most music program anyway. 400 is also a reasonable sub input to get a similar response out of a reasonably efficient sub, so something in the 2x350-2x500w range in the amp would be appropriate.
There are loads of options for class D amps, depends how DIY you're comfortable with going, how much you want to spend, and how reliable you want it to be. Sure Electronics do some pretty amazingly cheap class D chip amps with a DC voltage input. You could purchase 2x600w amps based on Texas Instruments TAS5601 (or similar, TAS56something) chips, plus a PSU/PSUs to power them for something in the region of $150 all in, and it would all come in at around 2kg total. But their QC is not the best in the world and there have been incidents reported on DiyAudio of the amps turning up and having a fault that's not immediately apparent impacting sound quality, that then needs fixing.
Being a chip amp you'd obviously need to be very careful not to slip and fry anything in set-up and assembly as well. I lost more than a couple of Class D boards like that.
So you get what you pay for, more or less, but you get a LOT for the money from Sure Electronics, and I'm overplaying the risk factor a little bit as a warning, but it shouldn't go un-noted. If you're still planning to cut sheet metal as part of your designs then you should be able to cut a neat backplate, buy a few off-the-shelf LEDs and switches, and set it up to look quite professional.
The other advantage with the Sure amps, if it's of any use to you, is you can run them from an array of 12v batteries (3 wired up in series for 36v) and take the system off-grid for times when generator or grid access is unavailable.
Actually, I just noticed that the Faital's in an array of 9 actually don't like a 400w input much at all. They're 3.6mm excursion at 200Hz, and I don't think they like more than 1.75mm (and you don't ideally want to be running your mids and highs on an woofer that's gone even close to it's xmax if you can help it).
If I were you, I would seriously consider running your crossover higher when you need high output, and run it lower only when playing lower output or inside rooms with appropriate acoustics. If you run the tops from 300Hz, the excursion with 400w of input is 1.68mm. If you have some headroom in your amp then you can safely/musically boost them by 3dB or more at frequencies from 400Hz and up.
You might be able to get away with a single Sure TAS5601 amp, with 2x300w, which you could probably pick up with a PSU for less than $80 - I haven't checked prices recently. Being able to put 600w into a sub would be optimal though, especially if it's lower efficiency than the tops.
Edit: Be careful to check impedances with amps and drivers obviously. Your 9 driver array presents some weird impedance issues surely? How are you wiring it currently?
The Sure amps are made in China but I think Partsexpress stocks them for a relatively modest markup so you can get them quickly enough in the US (and probably enhanced support for if something goes wrong if you go PE)
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No worries. You shouldn't have any issues with the sound quality of the Sure amps if they're all working as they should do. A lot of people are relatively happy with them unmodified even for hifi use, so for PA use? So long as they provide the watts you need, should be fine.
There are loads of threads on this forum dedicated to them and often with tips about which capacitors to replace in case of a dud or for enhancing the stock quality. But if ordered from a US retailer you should have a fairly easy returns process.
There are loads of threads on this forum dedicated to them and often with tips about which capacitors to replace in case of a dud or for enhancing the stock quality. But if ordered from a US retailer you should have a fairly easy returns process.
Oh yea. Trust me to fail at first grade maths problems!
The sort of things I pull up Windows Calc for you wouldn't believe... "50 x 10", "1 / 3", that sort of thing. I **** you not, it's muscle reflex. A forum asked me to solve an incredibly basic "find x" algebra problem the other day in order to sign up.. gave it a shot for a few minutes, then guessed until it wouldn't let me guess again, then gave up and refreshed until it gave me an easy question.
The sort of things I pull up Windows Calc for you wouldn't believe... "50 x 10", "1 / 3", that sort of thing. I **** you not, it's muscle reflex. A forum asked me to solve an incredibly basic "find x" algebra problem the other day in order to sign up.. gave it a shot for a few minutes, then guessed until it wouldn't let me guess again, then gave up and refreshed until it gave me an easy question.
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Ok. I know this is a bit of a stupid question. Seeing as how my speaker is loud as hell from 200hz up much more spl than I will ever need, and seeing as how distortion below 200 hz is pretty dang hard to hear in a PA environment, Seeing as how Bose got away with a few 5.5 in woofers in their "Acoustmess" "woofers" Would it be possible for me to use 1 or 2 of these units? Remember that I do not need any "Ultra Low" bass, just some basic "warmth" and enough "oomph" to drive my left hand "guitar type" keyboard bass in clubs? Can I make up the difference in spl with raw amp power, an acceptance of some distortion and the extremely long throw of these units? Hemi? Anyone? Dayton Audio UM8-22 8" Ultimax DVC Subwoofer 2 Ohms Per Coil
As an update. Just for the hell of it. I hooked up a little Kenwood 100w 8" home theater sub and set it at 200 hz.
Imagine my surprise that is almost kept up with the 9x 3fe25 "array" . In fact, I could see a lot of power getting wasted in excess cone movement, like a dc pulse before it settled down to "normal" movement. I am not talking about the transient of the bass guitar sound, I am talking of a "one direction" flop but the speaker still did not reach "X self destuct" It more or less held.
I will now plug the port and see of it still gets low enough. This should stop the "flopping" All of this is just a test to see what I can get away with. How small, how low, how loud is really needed for my personal situation. Will report.
Imagine my surprise that is almost kept up with the 9x 3fe25 "array" . In fact, I could see a lot of power getting wasted in excess cone movement, like a dc pulse before it settled down to "normal" movement. I am not talking about the transient of the bass guitar sound, I am talking of a "one direction" flop but the speaker still did not reach "X self destuct" It more or less held.
I will now plug the port and see of it still gets low enough. This should stop the "flopping" All of this is just a test to see what I can get away with. How small, how low, how loud is really needed for my personal situation. Will report.
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