Manning filters with inductor...

[TroyBoy]

Hi All,

New to posting on the forum.

I was looking at an SSS UL build thread on here with the Manning filter, and it sounded great.

I was wondering if anyone has looked at incorporating the inductor into this design?

I’m only asking as I have an inductor coming with my parts order.

Thanks in advance.

[martin manning]

I left the inductor out because it doesn't do anything.
See: https://ampgarage.com/forum/viewtopic.p ... 34#p410934

[TroyBoy]

Are we thinking about the design intent correctly though?

Could HAD have been using the inductor to reduce/filter noise prior to the signal hitting the filter?

Coils like this also offer saturation at an important part of the the signal chain (good noise). This type of saturation is the sought after sound in all those gorgeous old Neve consoles, which I think may be the intent here, and we could be missing something by not including it.

It has to do something in a circuit like this, as an inductor will have an impact on the impedance in relation to the frequencies hitting it.

So my thoughts are that whilst it will offer something “musical” to the circuit in terms of saturation, I also think it will impact the phase relationship with the signals bypassing the circuit, offering more harmonic complexity, it will also have a varying effect on the Q value of the eq based on its relationship to frequency, so I think this inductor will also be one the most “reactive” components of the filter section dependent on what’s being played.

I think we should experiment with including the inductor with your very well thought out filter design and check for difference.

Perhaps I could build this into my design, with the inductor being switchable.

Could be a worthy experiment...

Peace

[martin manning]

Several people have already tried shorting it out, and didn't hear any difference. Feel free to experiment, and by all means report back!