THAT 4301.. anybody try it?

I think this was discussed over at RO but nothing comes up in the search here.. Has anyone designed something with the thatcorp 4301 (analog engine)?

Done the 4301 one knob squeezer PCB layout a while back, still have not had the chance to test it out yet...... :sad:





Please let me know if there is any mistakes within the layout, I'll go ahead and fix fit. :thumb:

:guinness:

Funny, I came across my samples (that I've had for a while and haven't done a thing with) of this while cleaning at work today.

What about DN125? It shows the One Knob Squeezer and some other more expanded ideas. I've got a pair of samples that I'd give ya if you want to try the layout.

Peace!
Charlie

Hey Charlie,
That would be AWSOME!!! :green: :thumb:

The layout I have done is the very last one on the data sheet, Fig.11.
The reason that I haven't had the chance to test it is that I don't have an etching set up at home, so I have to try to get it done at college just never had the opportunity to do so......... :sad:

If you would like to try it out, PM me for the PDF version of it.

:thumb: :guinness:

I may have time to dig out my old etching supplies soon and give this a try, along with the PWM limiter of course..
but not for a few weeks though..

what is R1? it shows a 100k resistor but looks like it has three through holes under it.. ?

[quote author="Svart"]I may have time to dig out my old etching supplies soon and give this a try, along with the PWM limiter of course..
but not for a few weeks though.. [/quote]

Alright!!!! :thumb:

what is R1? it shows a 100k resistor but looks like it has three through holes under it.. ?

Click to expand...

R1 is actually VR1, the stupid PCB123 didn't allow me to put the V in there.

:guinness:

Are these 2 pcbs in sync? They don't seem to match up.

[quote author="Learner"]Done the 4301 one knob squeezer PCB layout a while back, still have not had the chance to test it out yet...... :sad:





Please let me know if there is any mistakes within the layout, I'll go ahead and fix fit. :thumb:

:guinness:[/quote]

[quote author="owel"]Are these 2 pcbs in sync? They don't seem to match up.[/quote]

Oh, my! R3/C6/R14 are moved about in the 2nd one. Looks like R14 was originally omiited from the tracks but is in place on the stuffing guide. Glad to know I'm not the only one who makes embarrasing mistakes! :razz:

Peace!
Charlie

Hey guys,
Good spoting!!! :thumb:

just thought I'll test you guys to see if anyone was paying any attention :wink: :green:

anyway, I went ahead and uploaded the new version for the PCB.

Cheers!

:guinness:

Uploaded where? Please post links.

hey, thanks for the work you're doing here and posting of the PCB layouts!

Hi owel,
I meant I've replaced the image file on this thread, if you want the layout in PDF please PM me your email address.

If anyone does a layout and wants a 4301 or wants to trade a 4301 for a PCB, send me a PM. I don't have to have a PCB for the chip, btw...they need a good home :grin:

Peace!
Charlie

The That's 4301 is a great little chip. Only drawback is that you are forced to use the internal opamp for audio duties. Otherwise, it really simplifies feedforward type processor design, espcially in multichannel or multiband topologies.

I've built several custom multiband boxes for broadcast stations using this chip, and they've all worked great.

JD, what do you mean you are forced to use the internal opamp... can't you just reroute it to go to your own opamp circuit?

The output of the VCA is internally strapped to the inverting input of the internal opamp. I called That's to find out if it could be bypassed, and they replied - negative.

This chip is fine for most designs for processors. If you're looking for a mastering type unit, or one with a more transparent audio chain, you'll have to find another chip (2150 series, 2181 series That or maybe an AD SSM2018T, or Aphex VAA).

would your impressions be more like the ssl or more like a standard dbx266 or something along those lines?

In it's basic form, setup as a FF compressor, it sounds similar to offerings from dbx, and other units that are FF with RMS detection. However, it is just a basic building block, and you can add additional timing circuits to create any sound you'd like.

In my multiband boxes, I added soft-knee thresholds with a dual time constant section that tracks the average level, and has an adjustable release time.

You could also set up the 4301 as a FB compressor. I've played with it a little, but not enough to comment on it's sound.