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Does BTL mode change the input sensitivity?

Trdat

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Essentially I have a Hypex NC502MP and two NC122MP and an NC252MP.

My 3 way standard system is doing okay with the NC252MP but when I push it hard it clips and I have been lazy to drop in the NC502 to see if I get more power, but I am wondering what the limits of the actual speakers is and hazarding a guess that although the 252MP clips the speakers itself might not be able to handle more power.

If I do switch them around(adding NC502 for the 3 way and the BTL NC122 for the DSP system) that means my DSP system with the amp feeding the Deltalite 2 2515 15 inch directly(8 OHM lowest impedance 6 OHM) will need the same power as the NC502 which delivers 200/220watts and the NC122MP in BTL mode according to the Hypex Spec sheet should deliver 200 watts into 8 ohms.

1. Does the input sensitivity change? I ask this because I push my horn/15inch very hard and would not want my SMSL SU-8 to clip the NC122MP.

2. Does switching amps change anything such as impulse response or group delay or any other factor in speaker design from software DSP? I ask this becasue I do not want to remeasure my system with Audiolense as everything is pristine in terms of tuning.
 

mdsimon2

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Assuming power doubles between 8 ohm stereo and 4 ohm stereo, input sensitivity between 8 ohm stereo and 8 ohm BTL will be the same. However, gain increases by 6 dB for BTL compared to stereo. Here are some example calculations showing this -> #121 and #564.

Michael
 
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Trdat

Trdat

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Assuming power doubles between 8 ohm stereo and 4 ohm stereo, input sensitivity between 8 ohm stereo and 8 ohm BTL will be the same. However, gain increases by 6 dB for BTL compared to stereo. Here are some example calculations showing this -> #121 and #564.

Michael
So does an increase in the gain mean that it will take longer to reach max power by 6db in this case? Did I get this right...?

I will check the two threads they look interesting. Thank you.
 
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Trdat

Trdat

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Actually the question that I should have asked is does the 6db in gain in the BTL mode match the gain of the NC502? I think that would give me what I am looking for right?
 

mdsimon2

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So does an increase in the gain mean that it will take longer to reach max power by 6db in this case?

I do not know what "take longer" means. 6 dB more gain means that you will get double the voltage out of the amp for the same input level.

Actually the question that I should have asked is does the 6db in gain in the BTL mode match the gain of the NC502? I think that would give me what I am looking for right?

The NC122MP, NC252MP and NC502MP all have a nominal gain of 25.5 dB when used in stereo. I do not fully understand your setup, but if you currently have multiple NCXX2MP amplifiers and are using them in stereo, and switch out one stereo amplifier with two BTL amplifiers, the BTL amplifiers will have 6 dB more gain. If you want to maintain the same balance between amplifiers, you will want to attenuate the signal going to the BTL amplifiers by 6 dB. If you are using a BTL NC122MP or NC252MP you will still be able to drive the amplifier to full power with 6 dB attenuation if you are starting with a DAC that has 4 V output.

Michael
 
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