Gain matching+filter setting

[KyleBrown 121]

So on this next run I plan on running my amps not strapped.

I know how to gain set with a DMM. Xovers I typically do by ear.

My plan of attack is to DD-1 both amps, check output voltage of both amps and match to the one with less output.

Now I'm not worried about setting the LPF on the amps since I can do that via the HU. My only area of concern is the SSF. I'm a little fuzzy on gain matching with the SSF.

Do you play your selected tone of choice (lets use 30hz in this example) continue to turn the filter up until you see a dip in output voltage? Then repeat on the second amp.

I'll most likely use Y-splitters for the RCAs to ensure proper distribution of pre out voltage instead of the output on the amps. Eventually I'll use some sort of Bass eq to bring the voltage back up.

[Impious 1,476]

Skip the DD-1. Gain match via DMM.

SSF setting is pretty simple. The SSF is nothing more than a highpass filter, which means the frequency that the SSF is set to is the -3db point of the signal (presuming they use a basic Butterworth type filter for the SSF).

Using your example; Play the 30hz test tone with the SSF knob turned all the way down (lowest frequency setting) or off. Measure the output voltage of the amplifier. The amount of voltage doesn't matter, literally doesn't matter, you just need to know what voltage you are starting at. Multiply the voltage you just measured by .707 and record your answer, this is your target voltage. Turn the SSF knob up until the voltage decreases to the target voltage. This means you've set the SSF so that 30hz is -3db, which means the SSF is set to 30hz.

So, let's say you play your test tone and measure voltage at 2V.

2 * .707 = 1.414V

Turn the SSF knob up until the voltage output from the amplifier decreases to 1.414V

Your SSF is now set to 30hz.

Repeat for 2nd amp. You don't have to start with the same initial voltage, just multiple the initial voltage by .707 and then set the SSF knob to that new target voltage. Now they are both set to the same frequency.

Last, I don't know what you mean by "Eventually I'll use some sort of Bass eq to bring the voltage back up." There will be very minimal loss of preamp voltage using a y-splitter, very possibly there will be no measurable loss. No need for a "bass eq to bring the voltage back up".

[///M5 2,833]

The DD-1 is a TERRIBLE marketing gimic that ONLY puts money into Steve's pockets. Completely useless in ANY application. You really don't want to waste any money on it, nor do I understand the desire to even have it.

[KyleBrown 121]

Skip the DD-1. Gain match via DMM.

SSF setting is pretty simple. The SSF is nothing more than a highpass filter, which means the frequency that the SSF is set to is the -3db point of the signal (presuming they use a basic Butterworth type filter for the SSF).

Using your example; Play the 30hz test tone with the SSF knob turned all the way down (lowest frequency setting) or off. Measure the output voltage of the amplifier. The amount of voltage doesn't matter, literally doesn't matter, you just need to know what voltage you are starting at. Multiply the voltage you just measured by .707 and record your answer, this is your target voltage. Turn the SSF knob up until the voltage decreases to the target voltage. This means you've set the SSF so that 30hz is -3db, which means the SSF is set to 30hz.

So, let's say you play your test tone and measure voltage at 2V.

2 * .707 = 1.414V

Turn the SSF knob up until the voltage output from the amplifier decreases to 1.414V

Your SSF is now set to 30hz.

Repeat for 2nd amp. You don't have to start with the same initial voltage, just multiple the initial voltage by .707 and then set the SSF knob to that new target voltage. Now they are both set to the same frequency.

Last, I don't know what you mean by "Eventually I'll use some sort of Bass eq to bring the voltage back up." There will be very minimal loss of preamp voltage using a y-splitter, very possibly there will be no measurable loss. No need for a "bass eq to bring the voltage back up".

Ok, that's what I was more or less looking for on the SSF setting. I assume it uses the type of filter, but I have no idea how to tell the difference lol.

Where does the .707 come from? Just curious so I can educate myself. Thank you for your input.

The DD-1 is a TERRIBLE marketing gimic that ONLY puts money into Steve's pockets. Completely useless in ANY application. You really don't want to waste any money on it, nor do I understand the desire to even have it.

I've had it for some time. I previously had a pocket o-scope which was very inconsistent and died in about two weeks. It works fine for what it is.

[///M5 2,833]

Not really. All it is is a device that doesn't do what is offered and does so at a dubious setting that isn't worthwhile. It has no value and benefit. Sell it while it still has value.

[pimpdaddy1787 1]

Not really. All it is is a device that doesn't do what is offered and does so at a dubious setting that isn't worthwhile. It has no value and benefit. Sell it while it still has value.

Would using an o-scope be better if I know how to use one?

What do you think would be a good price to sell a dd1 at? I'm going to sell mine

[ssh 924]

Skip the DD-1. Gain match via DMM.

SSF setting is pretty simple. The SSF is nothing more than a highpass filter, which means the frequency that the SSF is set to is the -3db point of the signal (presuming they use a basic Butterworth type filter for the SSF).

Using your example; Play the 30hz test tone with the SSF knob turned all the way down (lowest frequency setting) or off. Measure the output voltage of the amplifier. The amount of voltage doesn't matter, literally doesn't matter, you just need to know what voltage you are starting at. Multiply the voltage you just measured by .707 and record your answer, this is your target voltage. Turn the SSF knob up until the voltage decreases to the target voltage. This means you've set the SSF so that 30hz is -3db, which means the SSF is set to 30hz.

So, let's say you play your test tone and measure voltage at 2V.

2 * .707 = 1.414V

Turn the SSF knob up until the voltage output from the amplifier decreases to 1.414V

Your SSF is now set to 30hz.

Repeat for 2nd amp. You don't have to start with the same initial voltage, just multiple the initial voltage by .707 and then set the SSF knob to that new target voltage. Now they are both set to the same frequency.

Last, I don't know what you mean by "Eventually I'll use some sort of Bass eq to bring the voltage back up." There will be very minimal loss of preamp voltage using a y-splitter, very possibly there will be no measurable loss. No need for a "bass eq to bring the voltage back up".

Ok, that's what I was more or less looking for on the SSF setting. I assume it uses the type of filter, but I have no idea how to tell the difference lol.

Where does the .707 come from? Just curious so I can educate myself. Thank you for your input.

The DD-1 is a TERRIBLE marketing gimic that ONLY puts money into Steve's pockets. Completely useless in ANY application. You really don't want to waste any money on it, nor do I understand the desire to even have it.

I've had it for some time. I previously had a pocket o-scope which was very inconsistent and died in about two weeks. It works fine for what it is.

-3dB change = half power.

If you have 100watts from 10v*10a, then a -3db change would be 100watts / 2, so 50watts.

In order to drop from 100watts to 50watts from a change in both voltage & current, you end up with 0.707

0.707*10v = 7.07v

0.707*10a = 7.07a

7.07amps*7.07volts = 49.9849watts.

[KyleBrown 121]

Skip the DD-1. Gain match via DMM.

SSF setting is pretty simple. The SSF is nothing more than a highpass filter, which means the frequency that the SSF is set to is the -3db point of the signal (presuming they use a basic Butterworth type filter for the SSF).

Using your example; Play the 30hz test tone with the SSF knob turned all the way down (lowest frequency setting) or off. Measure the output voltage of the amplifier. The amount of voltage doesn't matter, literally doesn't matter, you just need to know what voltage you are starting at. Multiply the voltage you just measured by .707 and record your answer, this is your target voltage. Turn the SSF knob up until the voltage decreases to the target voltage. This means you've set the SSF so that 30hz is -3db, which means the SSF is set to 30hz.

So, let's say you play your test tone and measure voltage at 2V.

2 * .707 = 1.414V

Turn the SSF knob up until the voltage output from the amplifier decreases to 1.414V

Your SSF is now set to 30hz.

Repeat for 2nd amp. You don't have to start with the same initial voltage, just multiple the initial voltage by .707 and then set the SSF knob to that new target voltage. Now they are both set to the same frequency.

Last, I don't know what you mean by "Eventually I'll use some sort of Bass eq to bring the voltage back up." There will be very minimal loss of preamp voltage using a y-splitter, very possibly there will be no measurable loss. No need for a "bass eq to bring the voltage back up".

Ok, that's what I was more or less looking for on the SSF setting. I assume it uses the type of filter, but I have no idea how to tell the difference lol.

Where does the .707 come from? Just curious so I can educate myself. Thank you for your input.

The DD-1 is a TERRIBLE marketing gimic that ONLY puts money into Steve's pockets. Completely useless in ANY application. You really don't want to waste any money on it, nor do I understand the desire to even have it.

I've had it for some time. I previously had a pocket o-scope which was very inconsistent and died in about two weeks. It works fine for what it is.

-3dB change = half power.

If you have 100watts from 10v*10a, then a -3db change would be 100watts / 2, so 50watts.

In order to drop from 100watts to 50watts from a change in both voltage & current, you end up with 0.707

0.707*10v = 7.07v

0.707*10a = 7.07a

7.07amps*7.07volts = 49.9849watts.

thanks man