KABD-4100 amplifier noise floor

[illcrx]

Hey everyone! First time posting in the amp forum!

I have a Dayton KABD-4100 and the thing just hisses, I don't know how to measure it exactly but its very evident and more than I have heard in the past from other amps. I have this powered by a Meanwell Power Supply and when I unplug the input and the control board it just hisses. I have it running on a PC right now and that itself induces additional noise but just sitting there wondering what its doing with its life it just hisses.

Any recommendations on how to effectively lower the hissing on this thing?

 

[rayma]

Try it with a non-switching power supply (or batteries), and shorted inputs.
If there is still hissing, send it back for a refund.

 

[illcrx]

You want me to literally short the inputs left +/- and right +/- together? I guess that should cancel everything? I don't have another power supply for it, I can try to rig some batteries I guess. I don't have another power supply, I guess I can order one...

 

[rayma]

Short EACH of the inputs to ground. So any source of noise is guaranteed to be internal.

What kind of power supply are you using?

 

[illcrx]

Short EACH of the inputs to ground. So any source of noise is guaranteed to be internal.

What kind of power supply are you using?

The link is in the post to the PS

 

[rayma]

First try with shorted inputs.

Some switching power supplies can cause noise in the amplifier output.
Try with a different switching supply, or a linear supply.

 

[illcrx]

Grounding the inputs didnt' change anything, really though I just found a ground on the board and shorted all the input leads together, not sure if this is what you meant but I didn't hear a difference.

 

[rayma]

Then try a different power supply, or battery. Some switching power supplies are not intended
for low noise use. You may need a different one.

 

[ernperkins]

This board has 4 headers to connect pots to control different functions. It comes with a SigmaStudio project pre-loaded and according to the user manual "Out of the box, each KABD amplifier is pre-programmed for the potentiometers to have some basic functions,". The user manual shows the function of each pot and two are related to volume control. If you're not using the volume control pots the board may well be set to maximum gain. That would explain the constant hiss.

I should also mention the Dayton board is just a rebranded Sure (aka Wondom) Electronics JAB5 board. Wondom has several youtube videos on the JAB5, here's a LINK to one. Wondom also has JAB5 documents you can download from their website HERE. I suggest you download the JAB5 datasheet, it has the most information on the pre-loaded SigmaStudio project and what the pots control (it depends on the 4.0/2.0/2.1 configuration).

 

[illcrx]

This board has 4 headers to connect pots to control different functions. It comes with a SigmaStudio project pre-loaded and according to the user manual "Out of the box, each KABD amplifier is pre-programmed for the potentiometers to have some basic functions,". The user manual shows the function of each pot and two are related to volume control. If you're not using the volume control pots the board may well be set to maximum gain. That would explain the constant hiss.

I should also mention the Dayton board is just a rebranded Sure (aka Wondom) Electronics JAB5 board. Wondom has several youtube videos on the JAB5, here's a LINK to one. Wondom also has JAB5 documents you can download from their website HERE. I suggest you download the JAB5 datasheet, it has the most information on the pre-loaded SigmaStudio project and what the pots control (it depends on the 4.0/2.0/2.1 configuration)

Oh thanks, I am not using the pots! I'll take a look at that manual as well.

 

[jdubya]

Hello illcrx,

I'm considering the same amp for a project, and wondered if you ever solved this issue? Any advice on these amps?

Thanks!

 

[CameronDubs]

Having the same issue with an eminence f110m compression driver. Power supply is the one recommended by parts express. I am using the 3 way mono template for sigma studio which has master and treble control. Nothing would lower or change the amount of hiss coming from the speaker.