Looking for understanding and making sure I'm doing this correctly. I've got a Pioneer GM-D9601 and 2 Pioneer TS-SW3002S4 Bass speakers, that I took out of my truck before selling it to a dealership. I will be hooking them up to my pc at home and powering it with an extra atx 500w power supply I had laying around. The speakers are 400w nominal power and nominal impedance is 4 ohms each. The speakers are in a closed box so I cant see how they are connected, but I believe they are connected in parallels because I get a 2 ohm reading when using my voltmeter on the two speaker wires coming out of the box, is this correct in how I figured this? and does this mean I treat it like 1 800w 2 ohm speaker? Or do I treat it like 1 400w 2 ohm speaker?
According to the amp manual the amp can output 800w at 2 ohms.
So following the formula I multiplied 800x2=1600
then the square root of 1600=40v, is this right?
Next, with speaker wire disconnected I will be rotating the gain dial clockwise until my voltmeter reads 40v. Is this right?
I will be testing with a 50Hz 0dB audio file from my computer and routing a rca cable from the 3.5 speaker out jack on the pc to the rca in on the mentioned amplifier. Let me know if there is a reason I shouldn't do this.
Also, I wasn't sure if I will need it, as I'm not sure how the amp will respond to the signal coming from the pc. But I have a LC2i that came out of the truck as well. Would it be better to put this in between the pc and the mono amp?
Thanks for anyone's help on this. Would hate to blow anything up. this bass sounded amazing in the truck, just want to put these to use until I have a vehicle to put them in (wont fit in the car).
According to the amp manual the amp can output 800w at 2 ohms.
So following the formula I multiplied 800x2=1600
then the square root of 1600=40v, is this right?
Next, with speaker wire disconnected I will be rotating the gain dial clockwise until my voltmeter reads 40v. Is this right?
I will be testing with a 50Hz 0dB audio file from my computer and routing a rca cable from the 3.5 speaker out jack on the pc to the rca in on the mentioned amplifier. Let me know if there is a reason I shouldn't do this.
Also, I wasn't sure if I will need it, as I'm not sure how the amp will respond to the signal coming from the pc. But I have a LC2i that came out of the truck as well. Would it be better to put this in between the pc and the mono amp?
Thanks for anyone's help on this. Would hate to blow anything up. this bass sounded amazing in the truck, just want to put these to use until I have a vehicle to put them in (wont fit in the car).
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With only 500w of 12v power supply, you're not going to get more than about 350w out of the amp.
If you read 2 ohms for two 4 ohm speakers, they are in parallel.
Most amps work perfectly fine from a desktop computer's sound card output.
You don't need a line converter. The output of the computer is preamp level.
If you read 2 ohms for two 4 ohm speakers, they are in parallel.
Most amps work perfectly fine from a desktop computer's sound card output.
You don't need a line converter. The output of the computer is preamp level.
Perry Babin, Thank you for your response. What size Atx power supply would be needed? I have several laying around from old pc's I think I have a larger one somewhere around here. Alternatively I can combine two. Or is the Voltage the problem?
According to the amp manual the current consumption is:
14.4v DC (10.8v to 15.1v) and current consumption is 39 A (at continuous power, 4 ohms)
average current drawn is:
5.2 A (2 ohm for one channel)
According to the amp manual the current consumption is:
14.4v DC (10.8v to 15.1v) and current consumption is 39 A (at continuous power, 4 ohms)
average current drawn is:
5.2 A (2 ohm for one channel)
A computer power supply is going to be at or just below 12v, in most instances. Does this amp have regulation for the rail voltage or does the power output drop when the 12v supply voltage drops from 14.4v to 12v?
You're not at 4 ohms, you're at 2 ohms.
The current consumption at 2 ohms is likely a bit more than 2x what's given for 4 ohms.
'At continuous power' isn't very specific. Is that right at the onset of clipping? The current draw depends on the output level. Below clipping, the current draw will be less.
'Average current drawn' is meaningless. For the people who I dealt with, about 60-70 amps would be average. 5.2 amps is with the amp producing very little power.
An average 800w class D amp producing 800w RMS will likely need about 90-100 amps. A computer power supply would have to be capable of producing 90-100 amps from its 12v output. That would be a supply rated of about 1200w.
A 500w power supply may be good enough unless you are not willing to get less than 100% of the power that the amp can produce.
You're not at 4 ohms, you're at 2 ohms.
The current consumption at 2 ohms is likely a bit more than 2x what's given for 4 ohms.
'At continuous power' isn't very specific. Is that right at the onset of clipping? The current draw depends on the output level. Below clipping, the current draw will be less.
'Average current drawn' is meaningless. For the people who I dealt with, about 60-70 amps would be average. 5.2 amps is with the amp producing very little power.
An average 800w class D amp producing 800w RMS will likely need about 90-100 amps. A computer power supply would have to be capable of producing 90-100 amps from its 12v output. That would be a supply rated of about 1200w.
A 500w power supply may be good enough unless you are not willing to get less than 100% of the power that the amp can produce.
Thanks again for your response. Since I don't have anything laying around rated at that high of power, do you or anyone else know of a good cheap solution? It doesn't have to be atx, that's just what I had laying around. 1200w atx power supplies are pretty high in price. I was looking around on the web and found the HP DPS-1200, but open to other options. I of course wont be running the bass at full power all the time. Maybe only once in a while to show off to friends, but I like my hearing, and wouldn't want to disturb the neighbors too often either, lol.
In the home, you can expect FER less bass than in the vehicle due to the loss of cabin gain. You can put the woofers in a corner or closet which may help.
Why not try it with your 500w supply? If you're satisfied with it but you're friends aren't, let them buy the larger supply. As a side note, don't expect a huge difference from 350w to 800w. There will be some increase in bass but not much.
I don't have any suggestions for a supply. Maybe others will.
Why not try it with your 500w supply? If you're satisfied with it but you're friends aren't, let them buy the larger supply. As a side note, don't expect a huge difference from 350w to 800w. There will be some increase in bass but not much.
I don't have any suggestions for a supply. Maybe others will.
I'll go ahead and try it with the 500w atx. looking at the psu the 12v rail will only push out 26a/ 312w. So if I use the same formula as before but with the limitation of my power supply, then:
312watts x 2ohm = 624
square root of 624 = 24.97v
So ill give this a try and set the gain to push out 24.97v and see how it sounds. Having it so underpowered wont hurt it or sound bad? Or is it no different then just having the volume turned down, and wont be able to reach its full potential? I will have to wait until the morning to give it a try. Thanks again, I really appreciate having another opinion. Also is there anyone else out there who wants to chime in?
312watts x 2ohm = 624
square root of 624 = 24.97v
So ill give this a try and set the gain to push out 24.97v and see how it sounds. Having it so underpowered wont hurt it or sound bad? Or is it no different then just having the volume turned down, and wont be able to reach its full potential? I will have to wait until the morning to give it a try. Thanks again, I really appreciate having another opinion. Also is there anyone else out there who wants to chime in?
I don't understand what you're calculating. If the supply can produce only 26 amps, the power is 12x26 or 312w.
The amp isn't 100% efficient. It's likely about 85%. That means that the amp will produce 265w (approximately).
Setting the gain to a specific voltage is only good for a very limited number of amplifiers (mainly JL) and even then, most people are not satisfied with that setting.
What are you using for highs?
The amp isn't 100% efficient. It's likely about 85%. That means that the amp will produce 265w (approximately).
Setting the gain to a specific voltage is only good for a very limited number of amplifiers (mainly JL) and even then, most people are not satisfied with that setting.
What are you using for highs?
Sounds like he's trying to set the gains based on available amperage.
My advice would be to get a pro audio amp or plate amp and not monkey around with 12v amps in home, unless just testing.
My advice would be to get a pro audio amp or plate amp and not monkey around with 12v amps in home, unless just testing.
I asked about the high-end part of the system so that I might be able to make suggestions on the gains. I didn't get an answer.
Sorry for the late response, I spent to much time working on it (and enjoying it) and didn't have time to respond the other day. objext is correct, of the 10 or so videos I watched on this subject, this is the one that is probably the most straight forward and on point for what I was trying to do:
How To Set Amp Gain to Match Lower RMS Subwoofers? | Car Audio Q & A - YouTube
But, because my power supply isn't sufficient enough, I've done the math based on it rather than the speakers.
For the highs I'm using a 5.1 soundbar via toslink. I am using a converter/decoder for the toslink, one is passthrough toslink to maintain the 5.1 audio going to the soundbar and the other is decoded going to the mono amp via stereo rca.
Here is a link to my Speakers and amp in case you wanted to look at the specs:
https://www.pioneerelectronics.com/PUSA/Car/Subwoofers/Shallow+Mount/TS-SW3002S4?tab=manuals#specs
https://www.pioneerelectronics.com/PUSA/Car/Amplifiers/GM+Digital+Series/GM-D9601#specs
One thing I'm not sure if I have set correctly is the frequency, as I cant find much info on it for this unit, so I just turned the knob so that it lines up with the numbers. In this case the speaker specs say they go up to 125Hz so that's where I put it before setting the gain, hoping I did that right. Any insight on this would be great.
Compared to when it was in the truck, it definitely isn't as powerful, but then again I'm only giving it about 1/3rd the power that it can do, and like you said before about the cabin gain. But for now I think I'm happy with the results until I pickup the server PSU I mentioned above. Currently it sounds clean and a lot stronger than the bass that came with the soundbar.
How To Set Amp Gain to Match Lower RMS Subwoofers? | Car Audio Q & A - YouTube
But, because my power supply isn't sufficient enough, I've done the math based on it rather than the speakers.
For the highs I'm using a 5.1 soundbar via toslink. I am using a converter/decoder for the toslink, one is passthrough toslink to maintain the 5.1 audio going to the soundbar and the other is decoded going to the mono amp via stereo rca.
Here is a link to my Speakers and amp in case you wanted to look at the specs:
https://www.pioneerelectronics.com/PUSA/Car/Subwoofers/Shallow+Mount/TS-SW3002S4?tab=manuals#specs
https://www.pioneerelectronics.com/PUSA/Car/Amplifiers/GM+Digital+Series/GM-D9601#specs
One thing I'm not sure if I have set correctly is the frequency, as I cant find much info on it for this unit, so I just turned the knob so that it lines up with the numbers. In this case the speaker specs say they go up to 125Hz so that's where I put it before setting the gain, hoping I did that right. Any insight on this would be great.
An externally hosted image should be here but it was not working when we last tested it.
Compared to when it was in the truck, it definitely isn't as powerful, but then again I'm only giving it about 1/3rd the power that it can do, and like you said before about the cabin gain. But for now I think I'm happy with the results until I pickup the server PSU I mentioned above. Currently it sounds clean and a lot stronger than the bass that came with the soundbar.
There isn't much to calculate with the gains. You have to set the gains so that the highs and lows have the levels you want while being able to use about 75% of the volume control range.
What happens if the calculations have the bass too high or too low with respect to the high's output.
The frequency in the car I generally started with was 90Hz on the bass and about 125Hz on the highs. This left the midbass the cleanest and kept the voice/mids out of the subs. The thing is... tune it by ear, for the most part.
Going too high on the bass generally sounds bad and uses more power for no reason. Going too low on the high-end causes distortion due to the limitations of the highs amp and the small speakers.
What happens if the calculations have the bass too high or too low with respect to the high's output.
The frequency in the car I generally started with was 90Hz on the bass and about 125Hz on the highs. This left the midbass the cleanest and kept the voice/mids out of the subs. The thing is... tune it by ear, for the most part.
Going too high on the bass generally sounds bad and uses more power for no reason. Going too low on the high-end causes distortion due to the limitations of the highs amp and the small speakers.