Hello! Finally my Threshold is back totally fresh. I use this amp to drive my horn drivers and tweeters of my JBL 4560 speaker system and a Crown PSA2 just for the woofers. I know that 250w just to drive a pair of horn drivers and tweeters are many but i don't think that could cause any issue. Although i got a problem with the high input sensitivity of this amp. Because of that i got extended hiss on my horns and also is not easy to match from the electronic crossover the sensitivity of the 2 amps. A small move on thw volume of my preamp and the gain of the threshold goes to the sky 😛 Is there any way to reduce the input sensitivity of this amplifier? Best regards !!!
I think I understand what you want to accomplish.
I don't think you want to change/lower the input sensitivity of the amp. That's just the voltage to drive the amp to clipping. Lowering that won't accomplish what you want.
I think what you're describing is that you want to change the gain of either your pre-amp or amp. Depending on your pre-amp, another/additional solution could be also to use a stepped attenuator with with very fine steps, particularly at higher attenuation.
I don't think you want to change/lower the input sensitivity of the amp. That's just the voltage to drive the amp to clipping. Lowering that won't accomplish what you want.
I think what you're describing is that you want to change the gain of either your pre-amp or amp. Depending on your pre-amp, another/additional solution could be also to use a stepped attenuator with with very fine steps, particularly at higher attenuation.
Yeap the attenuator is what i was thinking. But im considering 2 thinks. One is its affect in sound, the second one is that the hiss remain even with the crossover and preamp off. Is there any way to low the sensitivity of the threshold?
Let's first determine what the issue may be.
If you have the amplifier hooked to your speakers with the inputs shorted (not connected to your pre-amplifier) - do you get a hiss? If you are not comfortable shorting the inputs, then just disconnect the pre-amp. If you still get a hiss, then you may need to have an experienced person take a look at options for the Threshold amp and/or potentially choose an amplifier more suited to your highly-sensitive horns. Hiss can be from many things, and chasing it and removing it particularly in very high power amplifiers with big transformers etc., could be a challenge. Dare I say, it may just not be the right tool for the job. However, if there is no hiss with the amp inputs shorted, then you can potentially have other options with the pre-amp. At least you will know where to focus your effort.
Then, if you connect the pre-amp does the hiss get louder? Does the hiss get louder / softer when you change the volume with no source connected?
Personally, I'd wait to determine what to do about the attenuation until after you determine the root cause / source of the hiss and see if you can get it to a level that is acceptable to you.
If you have the amplifier hooked to your speakers with the inputs shorted (not connected to your pre-amplifier) - do you get a hiss? If you are not comfortable shorting the inputs, then just disconnect the pre-amp. If you still get a hiss, then you may need to have an experienced person take a look at options for the Threshold amp and/or potentially choose an amplifier more suited to your highly-sensitive horns. Hiss can be from many things, and chasing it and removing it particularly in very high power amplifiers with big transformers etc., could be a challenge. Dare I say, it may just not be the right tool for the job. However, if there is no hiss with the amp inputs shorted, then you can potentially have other options with the pre-amp. At least you will know where to focus your effort.
Then, if you connect the pre-amp does the hiss get louder? Does the hiss get louder / softer when you change the volume with no source connected?
Personally, I'd wait to determine what to do about the attenuation until after you determine the root cause / source of the hiss and see if you can get it to a level that is acceptable to you.