[Holmz]

A cap across the tweeter pod and neg won’t reduce high freqs, it will load the radio down more as in theory at some freqs it could be a dead short, but it certainly won’t reduce voltage at the tweeter or the current through the tweeter, sorry but that is a waste of time
…

yeah it would require a resistor in front of it, otherwise the amp would just keep adding more high freq.

 

[Raiz]

in this instance i would consider a helix dsp with a dedicated dap or phone digital input so you can then set the vw hu as a main input and have it switch over for a set time if it senses signal on the main in, but you will get high quality digital audio from the dap

So the fix is to completely bypass the OEM head unit... 😕

 

[Holmz]

So the fix is to completely bypass the OEM head unit... 😕

If you are completely bypassing the HU then you could do that kid you have an amplifier.
But I lost track of whether or not you have an amplifier between the HU and the speakers???

If you do, then just get an iPhone to RCA and plug it in and see how that sounds.
That 8 to $15 should probably come before shipping for DSPs.

If not then you probably need the amp at some point anyhow and it will let you have some way to determine if the speakers are OK or not.

 

[dumdum]

So the fix is to completely bypass the OEM head unit... 😕

That’s not what I said… for music yes, but connect it so you keep your sensors, beeps etc

it comes down to if you can cope with the hiss, the answer is yes or no… no then an external dap is a good solution, if yes then just use it as it is

 

[dumdum]

yeah it would require a resistor in front of it, otherwise the amp would just keep adding more high freq.

But what does a cap do across the speaker terminals? A resistor will reduce levels regardless of a cap being present, I don’t get what the cap even does apart from present a potential short circuit at some freqs?

in a first order circuit when the cap is playing well above the crossover point it is effectively not there, ie a short… so the speaker plays whatever it does. So for example a 4 ohm tweeter with a crossover point of 3.5khz at 6khz the cap will add no resistance to the circuit and therefore the driver can play 6khz as loud as it coul were the cap not there

Now put that same cap over the + and negative terminals and at some freq it will become a dead short, how does that achieve anything? Do anything functional?

 

[Holmz]

But what does a cap do across the speaker terminals? A resistor will reduce levels regardless of a cap being present, I don’t get what the cap even does apart from present a potential short circuit at some freqs?

in a first order circuit when the cap is playing well above the crossover point it is effectively not there, ie a short… so the speaker plays whatever it does. So for example a 4 ohm tweeter with a crossover point of 3.5khz at 6khz the cap will add no resistance to the circuit and therefore the driver can play 6khz as loud as it coul were the cap not there

Now put that same cap over the + and negative terminals and at some freq it will become a dead short, how does that achieve anything? Do anything functional?

The OP wanted to try resistors, etc.

The cap across the +/- should short the high freqs, but only if there is a resistor before it, otherwise the amp will just drive it harder.

But yes an inductor is probably better.

 

[dumdum]

The OP wanted to try resistors, etc.

The cap across the +/- should short the high freqs, but only if there is a resistor before it, otherwise the amp will just drive it harder.

But yes an inductor is probably better.

I can only see that parallel load increasing load and distortion from the amp if I’m honest and don’t see how it would help at all as per my previous post

 

[Thomasluke7899]

I can only see that parallel load increasing load and distortion from the amp if I’m honest and don’t see how it would help at all as per my previous post

Bro...I tried like a week ago to explain.

 

[Holmz]

You guys are probably right.
(Because I think that OP still had it hissing.)

 

[Fish Chris 2]

In case I missed it, in a quick scroll....
I'm just curious how high you are having to turn your gains up ??? I had a Kenwood HU, that had issues, and I had to really crank up my gains, especially with my mono subwoofer amp, and that led to a lot of ugly hiss.
Ended up getting a sweet new Pioneer and immediately I was able to turn my gains down to less than half. Hiss immediately went away 🙂👍

 

[Raiz]

In case I missed it, in a quick scroll....
I'm just curious how high you are having to turn your gains up ??? I had a Kenwood HU, that had issues, and I had to really crank up my gains, especially with my mono subwoofer amp, and that led to a lot of ugly hiss.
Ended up getting a sweet new Pioneer and immediately I was able to turn my gains down to less than half. Hiss immediately went away 🙂👍

I'm not. I'm using direct replacement speakers on a factory head unit. No amp is installed. The hiss is present on both the factor tweeters and the aftermarket tweeter, but it is more pronounced on the aftermarket tweeter because it is more sensitive. This is all because the signal coming from the factory head unit is crap and needs to be corrected somehow.

 

[Holmz]

I'm not. I'm using direct replacement speakers on a factory head unit. No amp is installed. The hiss is present on both the factor tweeters and the aftermarket tweeter, but it is more pronounces on the aftermarket tweeter because it is more sensitive. This is all because the signal coming from the factory head unit is crap and needs to be corrected somehow.

You cannot remove the noise without removing the signal along with it.
So without a lower noise amplifier, and using the existing HU, there is not a lot of options left.

The only thing I believe that you could do is put something like 4 or 8 ohm resistor in series, and then a 4 ohm in parallel with the speaker +/-.

• That will attenuate the new speakers by 1/3rd using 2x 4 ohm resistors… so ~4-5 dB.
• And using the 8 ohm, in series, and the 4-ohm in parallel, will attenuate it by 1/5th or ~7dB.
• Using a single 4 ohm in series, with no parallel resistor, will give 1/2 or 3dB of attenuation.

You could probably get by with maybe using 1W resistors if you are not cranking it up too much… it should still get into the 95-100dB range which is usually enough for many people.

It may not sound great, but it should hiss less.