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Re: Next SINUS project??

Posted: Mon Feb 27, 2023 7:14 am
by radium98
Sinus pdf of single side is possible to me ? and i will wire the links missed,thanks?.

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 12:29 am
by LeeCavanagh
Is this mono or have I missed it on the drawing.
If you need two, do they link up?
Are you going to play with multi and next?

I remember Stephen’s com/lim on the super station in Manchester when I was on air, it did sound more expensive than it actually was (a bargain). So I guess that actually a good endorsement.

I’ve got one of motulous limiter pub boards. I could not source the components cheap enough (tried Cpc/farnell/rs , it’s just because I would only want 1 component , anyway I don’t want it so if anyone wants a pcb it should post for a 2nd class stamp which I have. (Also got the encoder board too which I also don’t need , I love his shiny blu boards, they look very expensive to make.

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 1:21 am
by sinus trouble
radium98 wrote: Mon Feb 27, 2023 7:14 am Sinus pdf of single side is possible to me ? and i will wire the links missed,thanks?.
No problem! :)

I will post them soon!

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 1:36 am
by sinus trouble
LeeCavanagh wrote: Tue Feb 28, 2023 12:29 am Is this mono or have I missed it on the drawing.
If you need two, do they link up?
Are you going to play with multi and next?

I remember Stephen’s com/lim on the super station in Manchester when I was on air, it did sound more expensive than it actually was (a bargain). So I guess that actually a good endorsement.

I’ve got one of motulous limiter pub boards. I could not source the components cheap enough (tried Cpc/farnell/rs , it’s just because I would only want 1 component , anyway I don’t want it so if anyone wants a pcb it should post for a 2nd class stamp which I have. (Also got the encoder board too which I also don’t need , I love his shiny blu boards, they look very expensive to make.
Yes you are correct! This a mono PCB and you will need two for stereo! :)

Albert kindly contributed some ideas for stereo which i will be looking into soon!

I am guessing the the "motulous" version is based on the "Pira" design? I have never tried it?

Sourcing components for a project can be time consuming? However, they are cheap and available!

I have done all the hard work for you! You can simply upload the Gerber that i posted to JLC PCB and they will make the PCB for you!! In any colour you want?

The PCBs are less than a quid each! The cost is mainly shipping from China!

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 6:33 am
by radium98
Thank you , for the hard work , to our hobie . Much appreciated.

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 9:48 pm
by LeeCavanagh
Yes thanks for the work, absolutely, but it’s postage for the odd component that bothers me, even eBay , yes not too bad if you can find all in one place.

Re: Next SINUS project??

Posted: Tue Feb 28, 2023 10:08 pm
by LeeCavanagh
2A7D704D-07C8-4CB5-B046-9A4EC5972810.jpeg

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 12:29 am
by Albert H
That's the "Pira" limiter / clipper. It works, but suffers from the problems common to all single-band limiters: a big bass thump will "dip" ALL the audio, causing nasty "pumping" effects. Also, the attenuator circuit (around the FET) isn't done properly, and will have large amounts of second harmonic distortion (particularly at around 6dB gain reduction). It's also mono....

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 12:51 am
by sinus trouble
LeeCavanagh wrote: Tue Feb 28, 2023 9:48 pm Yes thanks for the work, absolutely, but it’s postage for the odd component that bothers me, even eBay , yes not too bad if you can find all in one place.
No problem! :)

I completely understand how frustrating part sourcing can be! However, if you are interested in doing your own repairs or projects?

You can make things a bit easier with preparation! Whenever i am on a project, I have 90% of the parts in my stock already! :)

My advice would be to look out for Resistor, Capacitor (ceramic and electrolytic) bundle packs!

Especially ones that come packaged in a compartmental plastic case! These are ideal for keeping all components tidy and easy to find!

You can then top up on components that run low! :)

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 1:52 am
by sinus trouble
Anyways, Back to subject! :)

I wanted to give my findings on the Trimmer Pot on this design! As Albert confirmed, This setting is NOT a limiting control!!

This sets up the JFET operating conditions in conjunction with the output OP AMP stage known as "Pinch off"

Now its hard to explain to those who have never experienced this Limiter? But i would say the closest comparison is like "bias" in other circuits??

So! The original setup stated by Stephen works great! (apply 0Db signal and adjust accordingly)

Also if the Trim Pot is set centre by default? Everything still seems normal! Especially with just music!

However, With just speech? I noticed a tiny "crackle" on the peaks?

I am still experimenting? But i found that if i perform the setup proceedure, then retard the Trim Pot a touch extra? The results are much better! :)

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 3:19 am
by sinus trouble
Albert H wrote: Wed Mar 01, 2023 12:29 am That's the "Pira" limiter / clipper. It works, but suffers from the problems common to all single-band limiters: a big bass thump will "dip" ALL the audio, causing nasty "pumping" effects. Also, the attenuator circuit (around the FET) isn't done properly, and will have large amounts of second harmonic distortion (particularly at around 6dB gain reduction). It's also mono....
Albert is correct! Rev also mentioned this configuration too! :)

Lets be clear on the concept of this system! The particular limiter you use is not really relevant!

Some kind of "Active crossover" is the key here! I have used the same thing on past PA systems!

The premise of the "Active Crossover" is to split the audio band into 3 sections! (Or more) You would then process each band separately via multiple Limiters!

Whilst the performance is superb!! How practical is it to the average Pirate??

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 6:11 am
by radium98
thanks a lot , i still been waiting , when you have time for pdf or .lay

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 8:53 pm
by rigmo
LeeCavanagh wrote: Tue Feb 28, 2023 10:08 pm 2A7D704D-07C8-4CB5-B046-9A4EC5972810.jpeg
stereo pcb i have few if you interested

Re: Next SINUS project??

Posted: Wed Mar 01, 2023 11:25 pm
by Albert H
sinus trouble wrote: Wed Mar 01, 2023 3:19 am The premise of the "Active Crossover" is to split the audio band into 3 sections! (Or more) You would then process each band separately via multiple Limiters!
Whilst the performance is superb!! How practical is it to the average Pirate??
As a quick fix, I did a few 2-band limiters - bass up to 250 Hz on one limiter and everything from 250Hz to 15 kHz through the other. This largely overcomes the "pumping" problem, and doesn't cost too much to implement.

My basic limiter "engine" that I've been using has a quad op-amp for the sidechain and a dual op-amp for the attenuator stage and for the "make-up" gain stage. The attenuating element is a linearised FET (or rather two FETs!) and the time constants can be adjusted for the different parts of the audio spectrum. The separation filter at the beginning of the limiter is a "phase-linear" type, and gives a smooth transition from one band to the other. After the limiters, the audio is recombined with a simple active mixer stage. Subjectively, it sounds really good, and isn't too expensive for pirates.

I didn't bother with gain reduction meters - just LEDs to indicate that the stage is in limiting - but adding the meters wouldn't be difficult (I'd use either LM339 comparators or LM324 op-amps for cheap LED meters).

If you want to go a stage further, I also came up with a 3-channel version, with crossovers at 250Hz, 250Hz - 1600Hz and the rest up to 15 kHz. After some experimentation and extended listening tests, I found that the 3-band version was slightly better than the 2-band, but I'm not sure that the additional complexity and expense can be justified.....

I'll put the circuit and suggested PCB layouts up here over the next couple of days.

Re: Next SINUS project??

Posted: Sun Mar 05, 2023 12:32 am
by sinus trouble
Cheers Albert! :)

I would be great to see your ideas! :)

Audio spans such a broad range of frequencies and listening preferences! A single limiter will struggle!

I dont wanna sound like a eccentric "Audiophile" here! But i am not a big fan of Graphic EQs either!

My reasoning for this is that a "Sound Engineer" has spent hours or even days perfecting a particular sound!

So my conclusion is? How do we preserve the beautiful clarity whilst preventing over modulation?

Re: Next SINUS project??

Posted: Fri Mar 10, 2023 10:48 pm
by LeeCavanagh
Sounds like you just want a leveller with a slow release and virtually no compression. You can pick them up from some good brands at low 2nd hand ebay prices.

Re: Next SINUS project??

Posted: Sun Jul 23, 2023 9:50 pm
by hailstorm
I've just finished building the Sinus Limiter (well a pair of them for stereo) and they sound amazing.
Sounds just as good as the Veronica ones I had in 1997. Thank you Sinus and everyone who helped!

Re: Next SINUS project??

Posted: Mon Jul 24, 2023 8:54 pm
by radium98
Wonderful .can you please give us a visual video to get inspired by the art with different
Level inputs and showing how to output behave constant .thanks for you and sinus

Re: Next SINUS project??

Posted: Tue Jul 25, 2023 2:17 am
by hailstorm
I'll work on getting a video done, meantime this is what the processor does.
audio input.png
audio output.png
This is a recording of the output, although Soundcloud have reduced the bit rate of my wav file so it sounds much better in real life.



Even the Cola Boy track survives without being mangled - surprising for a single band processor.

Re: Next SINUS project??

Posted: Tue Jul 25, 2023 3:29 am
by Albert H
The reason that it sounds pretty good is that Stephen Moss spent a lot of time getting the time constants right. The attack isn't too fast, and the dual release time constants work well. For a single band limiter it works pretty well.