Hey guys, I thought I'd share this. I did a looped-back response of the Dayton Audio SA100. The feed to the amp was crossed over at 90Hz (lowpass).
I drove the amp to 1 watt into a dummy load/voltage divider. A calibration file was loaded to take the low rolloff of the AVR out of the equation.
Anyone considering this amp should be aware that at 20Hz, it's response will be down a little more than 10dB not counting the rolloff of your signal chain and driver's response.
I drove the amp to 1 watt into a dummy load/voltage divider. A calibration file was loaded to take the low rolloff of the AVR out of the equation.
Anyone considering this amp should be aware that at 20Hz, it's response will be down a little more than 10dB not counting the rolloff of your signal chain and driver's response.
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That's (not) good, considering those newbies wanting response of the system & driver to F3@20Hz.
It would make using boosting an obligation for all speaker designs.😀
It would make using boosting an obligation for all speaker designs.😀
Can you elaborate? I don't really get it.
Is it not true that an ideal speaker/amplifier system has a frequency response that is essentially flat between 20Hz and 20kHz? With such a system any flaws in energy distribution across the frequency spectrum are room-related, not the fault of the system.
It's true that room gain helps in (acoustically) boosting the low-end, but that also involves exciting room modes; and it's behaviour is, for most people, quite unpredictable.
Am I talking out of my a** now? Please tell me if I do. I'm trying to get a grip on what room gain actually does in relation to a systems' specifications.
Haha, I love you guys from the Netherlands because you are straight up. What my point is:
Basically that an amplifier that cuts off a significant part of low end frequencies is not ideal. Same with a receiver or an EQ for your sub. All of these pieces of equipment will have some rolloff. Once it adds up and you combine it with the natural rolloff of your subwoofer you can easily loose octaves worth of content.
This amp is 11dB down at 20Hz. That is like hitting a brickwall of rolloff. Room gain is not going to help you out if an amp has rolloff down low like this. I have even tried to counter amps that rolloff like this one with EQ and it only makes a small difference. Some things are not designed to be full bandwidth and you can not make them be no matter what you do.
It is a good example of how one thing in the system can ruin your response.
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Designed that way to protect the driver, perhaps? That sucks, if you buy a large subwoofer system and you can't get anything below 27Hz from it...
Commercial subwoofers have limiters to flatten response and to protect against low frequency transients, or highpass filters to totally stop low information from damaging components. Some preamp or EQ manufacturers highpass filter so that their equipment has a lower noise floor. On the other hand there are some great designs that have more than enough headroom and don't have any rolloff at all down low.
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