Should I?

[[silent:arts]]

[quote author="no-fi"]one more bump for audio.[/quote]
why ?
audio is subjective :roll:

 

[no-fi]

yes..... it is... well... aspects of it can be.

but what's that got to do with me wanting to hear some audio samples of instruments before and after processing?

....especially if there are some existing already, and there's web hosting space ready to go?

 

[DerEber]

[quote author="no-fi"]yes..... it is... well... aspects of it can be.

but what's that got to do with me wanting to hear some audio samples of instruments before and after processing?

....especially if there are some existing already, and there's web hosting space ready to go?[/quote]

Then its less fun to build it. :green:
Everyone can DIY his own samples soon. :thumb:

 

[analag]

I sent a before and after file to Volker to host. When you look at the processed file you will see the difference in volume and dynamics. I did not normalize it so the effect of the compressor on the audio is more apparent.

analag

 

[analag]

Here is a little thingy I put together as a quick demonstration fer ya peeps.
Before:
http://groupdiy.silentarts.net/pm660/PM660-1.wav
After:
http://groupdiy.silentarts.net/pm660/PM660-02.wav

analag

 

[tommypiper]

Mmm. Well I've only listened on the computer with crap headphones through the crummy converters... haven't looked at the waveforms. But very hard to tell... I'm not hearing the same effects as in Bernd's samples. Probably because the settings are milder?

Seems to add a sense of urgency, without any pumping or compression artifacts.

This poor little man has a big bottom.

:guinness:

 

[analag]

Actually I was driving her pretty hard. The sidechain and cathode bias voltage determine the input dynamic range. I will post my voltages in the help thread, when the builds get going.

analag

 

[Viitalahde]

Hey, I like the sound! :thumb:

Inspires me in the journey of designing my own Moo. I'm thinking of 4x PCC189's in parallel, but a push-pull Mosfet amp with a similar biasing scheme to Fairchild for ratio adjustment.

The Fairchild type compressor is a nice base for experimenting, and supports my "keep it modular" approach. I'm building a passive EQ right now, and it's going to be a thing where every portion of the circuit can be easily changed later on if I feel like improving it.

Same thing with the Fairchildish compressor.. For a mono prototype I can start with 4x PCC189's and 600/10k & 10k/600 Edcors. Build a PSU, hook the grids to a variable supply (or perhaps a simple square-wave LFO), and when you've made it linear for a given amount of GR, add a SC amp, rectifier.. All I need is a big piece of wood and time.

 

[no-fi]

thankyou!! I really like what it does to the solo piano at the start.

 

[Moby]

Thanks Analag. I like the character but there is no huge difference in the RMS. If I counted well something around 1.6db. Did you tried to squeeze it more?

 

[analag]

If I could I would post the waveform, the processed one is almost devoid of peaks. Setting was 3dB reduction at medium attack, and yes I could've squashed it more but decided against it.

analag

 

[Moby]

I analyzed (and listened) the files again and I'm confused.. :? How is possible that processed file has "more" dynamics? Well, listening and comparing without normalizing sounds confusing to me so I normalized the files. Btw, "before" file is a bit clipped :wink:

 

[tommypiper]

Yes, it might be helpful to hear it with an original file which has more dynamics to start with. Anyway, we're all going to be building it anyway, so it's somewhat a moot point now, more for curiosity and discussion.

 

[Moby]

[quote author="tommypiper"]Yes, it might be helpful to hear it with an original file which has more dynamics to start with. Anyway, we're all going to be building it anyway, so it's somewhat a moot point now, more for curiosity and discussion.[/quote]
yes I'm inpatient because I'm waiting for my pcb's but curious too as well . I'm sure that I'm not the only one ;-)

 

[ognam2]

thanx for the sound files...
Sounds good.
But I would also like to hear something with more GR....

Jonas

 

[Moby]

Yes, it might be helpful to hear it with an original file which has more dynamics to start with

Now I'm confused again :? Isn't the "before" file (PM660-1.wav) original file? Or to be more precise, file without PM660 processing?

 

[seavote]

moby you are correct: pm1 has no compression
pm 2 has the pm660 applied to it.
tommypiper was saying a file with greater dynamic range, would allow us to more easily hear the pm660s effect. the piano has the greatest dynamic range. that piano hit in the intro is compressed quite a bit.

 

[Moby]

I was confused because when you normalize the processed file and measure the RMS is lower. Must be because PM is sensitive to low end energy...or whatever :?


PM660/1 RMS level (dB) L/-15,611 R/-15,828

PM660/2 RMS level (dB) L/-17,210 R/-17,432

 

[zebra50]

I haven't seen the waveforms for these but...

... of course the compressor is not infinitely quick, so there will be a transient before the compression kicks in.

Normalising will simply peg the loudest transient to 100% in each case. So in this case one would expect the compressed signal to have a lower RMS.

 

[Moby]

Does PM660 has variable attack? maybe Analag adjusted to few100ms?