evilcat
Well-known member
Congratulations for your work!!! Definetly a very interesring thread.
etheory - a bunch of projects in progress
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etheory
Well-known member
I get distracted too easily....
Class A make-up gain design I whipped together and did a board design for that I would love to pair with Ian's REDDEQ design.
Probably will also offer these for sale assuming they work of course ;-)
The simulator says performance is absolutely outstanding, promising some truly ridiculous clean signal swings up to and beyond +-12V at about 3W, but reality is often different, will let you all know....
Class A make-up gain design I whipped together and did a board design for that I would love to pair with Ian's REDDEQ design.
Probably will also offer these for sale assuming they work of course ;-)
The simulator says performance is absolutely outstanding, promising some truly ridiculous clean signal swings up to and beyond +-12V at about 3W, but reality is often different, will let you all know....
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etheory
Well-known member
Yessss! The trailer for the LEGO Movie is finally out.
This is what I've been working on and the reason these projects aren't progressing as fast as they could be:
http://www.youtube.com/watch?feature=player_embedded&v=lPnY2NjSjrg
This is what I've been working on and the reason these projects aren't progressing as fast as they could be:
http://www.youtube.com/watch?feature=player_embedded&v=lPnY2NjSjrg
evilcat
Well-known member
At what level are you involved in this Lego Movie project? The graphic quality is awesome!!! And the trailer is really fun, well done!
etheory
Well-known member
I'm a software engineer at Animal Logic (the CGI vendor) and I write rendering-related software and work on image generation algorithms and tools.
I work in the lighting department and my primary job is making sure everything software-based works so that we can render the images fast enough and deliver on schedule.
Some of this is designing and writing new software, other times it's working with existing tools to fix them or make them faster.
I work in the lighting department and my primary job is making sure everything software-based works so that we can render the images fast enough and deliver on schedule.
Some of this is designing and writing new software, other times it's working with existing tools to fix them or make them faster.
Dammit! You're good at making me want projects I didn't know I needed....
... Do you secretly work for Apple Inc.?
;D ;D ;D
I'm now thinking I need to build a REDDEQ in a 500-unit with one of those make-up boards... and there I was thinking I'd managed to control the DIY bug!
CHEERS!
8)
... Do you secretly work for Apple Inc.?
;D ;D ;D
I'm now thinking I need to build a REDDEQ in a 500-unit with one of those make-up boards... and there I was thinking I'd managed to control the DIY bug!
CHEERS!
8)
etheory
Well-known member
OK, so, after countless hours of toying around, I'm finally satisfied with the frequency response of the e274 amplifier section.
The biggest embarrasment was measuring at what I thought was 96kHz, and getting a strange wobbling and huge dip just before 20kHz.
After changing pretty much all the analog sections in order to hunt down this issue, stupid me realizes that my sound card was overriding the RMAA settings to 44.1kHz and the pre-sampling filter was ruining the high end (faceslap).
ANYWAY! Now we are finally getting there.
I'm just tuning some basic things like the values of caps to give me good performance for different settings.
I know it's taking ages but I hope it'll be worth it ;-) I'm spending an hour or two each weekend to finish it off.
The biggest embarrasment was measuring at what I thought was 96kHz, and getting a strange wobbling and huge dip just before 20kHz.
After changing pretty much all the analog sections in order to hunt down this issue, stupid me realizes that my sound card was overriding the RMAA settings to 44.1kHz and the pre-sampling filter was ruining the high end (faceslap).
ANYWAY! Now we are finally getting there.
I'm just tuning some basic things like the values of caps to give me good performance for different settings.
I know it's taking ages but I hope it'll be worth it ;-) I'm spending an hour or two each weekend to finish it off.
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etheory
Well-known member
ramshackles
Well-known member
Hey, just a quick off topic question - I presume you are using a software 'scope? What is it?
I have a couple of freeware ones but find them to be largely unhelpful.
Keep up the good work! I am quite interested in your make up gain card..
I have a couple of freeware ones but find them to be largely unhelpful.
Keep up the good work! I am quite interested in your make up gain card..
etheory
Well-known member
Hi Ramshackles!
I use RMAA: http://audio.rightmark.org/download.shtml with an RME Fireface 800 sound card.
The make-up gain Class-A transistor-based amplifier is something that I will be prototyping very shortly, hopefully within the next month.
I'll be sure to keep this thread posted about that and the final stages of the e274 including the first prints and when I have successfully constructed and verified one of them before offering them for sale.
regards.
I use RMAA: http://audio.rightmark.org/download.shtml with an RME Fireface 800 sound card.
The make-up gain Class-A transistor-based amplifier is something that I will be prototyping very shortly, hopefully within the next month.
I'll be sure to keep this thread posted about that and the final stages of the e274 including the first prints and when I have successfully constructed and verified one of them before offering them for sale.
regards.
etheory
Well-known member
mig27 said:
Sorry, yes, all of these projects are still alive.
I just have a very slow time scale at the moment ;-)
I just got back from a two week holiday to Perth/WA/Margaret River for some well-deserved R&R/Wine/Food. So nothing happened then.
Since being back and just before I left, my work (day job) has been pretty busy as we work towards delivering the film at the end of the year.
I am currently doing my tax, which is a downright nightmare and always takes me ages and ages.
I'm also starting a software company.
Basically I'm doing too many things at once, and progress is pretty slow.
So everyone will have to have a lot of patience but I'll get there eventually ;-)
I have a reasonable working prototype of the e274 but I'm not happy with the output section and have been toying with a possible variable threshold. So I'd like to resolve those design issues first.
Thanks for checking in!
etheory
Well-known member
mig27 said:Sounds great!
Hope I didn't come off impatient, but your sound samples just keep ringing in my head and I can't wait to build a couple of e274's
No, no, not at all. It's all good!
I am as keen to get back to this as you are to hear it ;-)
Won't be too long, hoping to get back to it within the next 2 weeks.
etheory
Well-known member
I couldn't resist snapping up one of these Texas Instruments PCM4222EVM evaluation boards for a rainy-day project to add some even nicer ADC's to my RME Fireface 800, and for recording my analog synths with as much clarity as I possibly can.
Of course, in the distant future when I actually get time to turn this into a 1U racked ADC, I'll write it up for people to check out:
Of course, in the distant future when I actually get time to turn this into a 1U racked ADC, I'll write it up for people to check out:
shot
Well-known member
Oh... I wish you released pcb's of those compressors you were working on few pages ago...
etheory said:
etheory
Well-known member
I will, I promise, I have been absolutely swamped at work lately, so haven't had much time for anything else.
I have some time approaching, I haven't disappeared I promise!
I have some time approaching, I haven't disappeared I promise!
etheory
Well-known member
I'm back!
I started with a quick little project to get me back into the swing of things before completing the compressor projects, and it was an outrageous success.
It's the class A 24dB makeup gain stage (which I previously mentioned) that I modified from the basic JLH amplifier design to perform make up gain for passive EQs.
Worked first turn on perfectly.
Can use AC or DC coupling at the output (can be trimmed to output a signal with no DC offset).
Next step is the passive EQ to pair it with of course ;-), but that'll come later.
Will take some measurements soon.
This will be one of the first PCB's I'll make available in small quantities when I get my web-store up and running. A nice version of course, not a CNC'ed one ;-)
All that space to the right is for 3 large axial caps that will go on the production version. I left them out of the test version as my PSU has plenty of filtering. The crappy cheap electro caps are placeholders for experimentation, but they work just fine. I've specced out axial polys for the final version, should you want to use them.
I started with a quick little project to get me back into the swing of things before completing the compressor projects, and it was an outrageous success.
It's the class A 24dB makeup gain stage (which I previously mentioned) that I modified from the basic JLH amplifier design to perform make up gain for passive EQs.
Worked first turn on perfectly.
Can use AC or DC coupling at the output (can be trimmed to output a signal with no DC offset).
Next step is the passive EQ to pair it with of course ;-), but that'll come later.
Will take some measurements soon.
This will be one of the first PCB's I'll make available in small quantities when I get my web-store up and running. A nice version of course, not a CNC'ed one ;-)
All that space to the right is for 3 large axial caps that will go on the production version. I left them out of the test version as my PSU has plenty of filtering. The crappy cheap electro caps are placeholders for experimentation, but they work just fine. I've specced out axial polys for the final version, should you want to use them.
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