Solo X Question

[jsmoke222000]

So WTF would you do if you had an Eclipse Cd7200 with 8 volt preouts?

[Crump]

This is how I have always set the gain on my amps without a oscope:

Most audio equipment dies for one simple reason. Most people push their equipment beyond its limits. Whether it is the amplifier, subwoofer or full range speakers, clipping is the number one cause of failure. To prevent clipping, use this tutorial.

To figure out what voltage you should set the gains to, multiply the RMS power of the amplifiers output by the impedance of the speaker, then find the square root of that number. If you are using an amplifier that has an RMS rating of more than your speaker(s) can handle/rated for, then use the RMS rating of the speaker (instead of the RMS of the amplifier) to determine the voltage to set your amp to. This is also referred to as gaining down.

Gain Setting Equation

Voltage of the output = sqrt(RMS Power X impedance of the speaker)

Example

Say the amp provides 2700WRMS into a 2 ohm speaker: (zx2500.1 & solo x 2 ohm load)

Voltage = sqrt(2700W X 2 ohms)

Voltage = sqrt(5400W)

Voltage = 73.5V

Again, that was only an example for this zx 2500.1, use the ratings of your amp to figure that out.

Setting the Gain(s)

To set the gain(s), you need two things:

1. A DMM (digital multi-meter) that is capable of measuring AC voltage (needs to be able to measure up to a range of 200V).

2. A test tone CD to use to set the gains at the correct setting.

Now, to set the gain(s):

1. Start the vehicle, and pop the test tone CD in the head unit.

2. DO NOT hook up the sub(s) or speaker(s) to the amplifier while doing this, just leave the outputs unused (unhook your speaker wires) at this time.

3. Now, time to set up the head unit.

a. Turn your radio up to the loudest setting that you will be playing it @, set your bass boost, loudness, ect. on your radio, use those settings. NEVER turn the headunit above 3/4 of the maximum volume.

b. Remember to have the car turned on.

c. If you want to use bass boost on a sub amp, set it prior to setting the gains on the amp and use the center frequency of the bass boost (45 Hz for most amps) as your test tone.

d. Please remember that if you have a subwoofer volume control on the headunit and/or a bass knob for the amplifier, set it to the maximum before you set the gains on the sub amp.

4. Take the leads from the DMM and but them on the speaker outputs from the amp.

5. Set the gain so that the outputs of the amplifier equal the voltage you found above. This is pretty important. If you set your gain higher than the voltage you calculated, you will be sending a clipped signal to your speakers.

This should get you very close to your clipping point of your amp. If you have access to an oscope you can get it perfect because you will be able to see the sine wave of the test tone note.

I thought it was square root of rms power x 0hm load at the amp. and then set your gain at that voltage?

i got this from here

http://mobile.jlaudio.com/support_pages.php?page_id=143

[jsmoke222000]

I thought it was square root of rms power x 0hm load at the amp. and then set your gain at that voltage?

that is correct. 73.485 x 73.485 = 5400 I just rounded up to 73.5 volts.

[Guest]

So WTF would you do if you had an Eclipse Cd7200 with 8 volt preouts?

put the gain down all the way on the amp. and turn the headunit volume up to where you get as much preout voltage as your amp can handle.

[Crump]

that is correct. 73.485 x 73.485 = 5400 I just rounded up to 73.5 volts.

So 1000 rms x 1 ohm load= 1000 sqrt of 1000 = 31.6 so my gain should be set at 31.6 Ac volts?

[audiofanaticz]

So WTF would you do if you had an Eclipse Cd7200 with 8 volt preouts?

You go into your headunit settings for subwoofer preout level and turn it down til your getting ruffly the maxium voltage your amp will take.

[GIMNICK]

damn 1/16 how low should i turn my gain?

[jsmoke222000]

set your gain with a volt meter. Probably gonna have to wait until I get back to do it though. You will need a test tone cd. I added a Gain Settings calculator to my audio calculations spreadsheet. You will need to have microsoft office installed on your computer to use it because it is in microsoft Excel. http://www.3rdcoastcustoms.net/files/3rd_C...Spreadsheet.xls

[jsmoke222000]

Here are some free test tones you can download & burn to cd. http://www.ronelmm.com/tones/

[Darksideofsound]

damn 1/16 how low should i turn my gain?

ya, that was when i didn't know how to set it properly, and that was the suggested amount to turn my gain up....primitive i know......