Budget de-esser frequency mod / ext sc

[vitopower]

I want to hardware duck 100-300hz via ext sidechain. Fast attack only would be ok, a variable release and q control would be ideal.

Is there a de-esser that would be suitable for this type of mod, or a cheap compressor?

I've looked at the dbx902 which has hp, lp sections but it gets too complex for me to to tell if it would be suitable. The manual and schem are in tech docs but I don't know if it is OK to post here.

 

[Script]

Just an EQ in a compressor side chain for isolating the offensive frequency band before the detector? Or too crude cos full-band attenuation?

Or, if this is a "Lab" question and quality of hardware is not an issue, any old thru-hole PCB Behringer compressor might do for hacking into a dedicated "100-300hz ducker". Variable Q control means active filter tho.

 

[vitopower]

ありがとうございます！日本語を勉強しています。 I would like to only duck the 100-300hz range of the output, as though I was using a multiband compressor with an external sidechain input. There is a great post here on making a 3 way mulitband gssl, but the band splitting and parts involved looked cost prohibitive. I thought maybe because a de-esser is only removing a specified range, perhaps that frequency range could be shifted and this could work, but I am way over my head.

 

[Script]

Then you probably also read that multi-band processing not only requires a lot of components and meticulous matching but that splitting bands and summing them again can result in phase issues.

Just as an idea, maybe use a parallel subtractive approach? Needs three channels on a mixer:
- (1) material to mixer (mute 'on' at first)
- (2) material into EQ into comp into mixer
- (3) output from EQ also straight into mixer, but polarity flipped and level-matched with (2)

Send 'material' into an EQ and 'isolate' (boost, HP, LP) the offensive frequency band. Take that and send it thru a compressor at unity gain. Then 'sum' the output of the compressor with a signal straight from the EQ output but flip the polarity of the EQ line in the summing. Thus, EQ output and comp output are in parallel. If levels are matched and everything else is perfect, the two signals should cancel out. Then start attenuation on the comp. You should start hearing the 'difference' between the two signals, namely the part that gets attenuated down by the compressor (if it was sibilance, then just the isolated 'sss' sound). However, that 'difference' signal is polarity flipped, which is the basic idea, because if you finally 'sum' that with the (now unmuted) 'material', it will subtract or cancel out in the final sum.

I guess there will be phase issues too, but should work somewhat nicely in a DAW with plug-in latency compensation.

But don't take my word for anything, the above might be wrong -- it's Tokyo and we had degrees of 35C indoors today, now down to 32C---

頑張ってね

 

[vitopower]

Cool idea, never tried this, thanks!

 

[Script]

I think it's called dynamic EQing.

Other units:
BSS DPR402 is maybe a candidate. A split-band de-esser, but freq is not that low on that unit -- either wideband or high freq.

 

[kags]

I want to hardware duck 100-300hz via ext sidechain. Fast attack only would be ok, a variable release and q control would be ideal

A dynamic EQ with a side chain seems like a good solution. That would be digital, though. IZotope, Waves, FabFilter, and prob a few others provide these features.

The BSS 402 mentioned above is a powerful analog box. Possibly the TubeTech multi band comp would work- although the crossover might bother you.

 

[abbey road d enfer]

DPR 901 is the dynamic EQ in the BSS range. They don't come cheap though.
It's the only commercially available box that does it. No one has tried to produce a different version. This product came at a time when processing was becoming more and more digital/plugins.
Considering the high cost of manufacturing, nobody gave a try at copying it.

 

[Script]

Yes, the DPR 901 even features the frequency band OP asked about and F.P. says Bell Width.

Attack and release are not controllable (only fast release switch).

Build one from scratch? -- DIY nightmare.

As for maintenance, well, the VCAs are obsolete by now (would need adapter board) and replacement pots are not easily available any more (if at all).