mid level console semi-parametric EQ redesign
- Thread starter danielle
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Hey Butta
I'm wondering what to do EQ wise for that MC2404 desk i picked up and mebbe this design could be good?...what do u rek?
I've striped the whole thing (was pretty messy n tatty neways - was only 80 quid afterall ;p) and looking at the brds they are chok fulla carbon resistors, ceramic caps and moody opamps - i dont think modding the brds themselves is feasible anymore as I'm already gonna be using the panels/frame for a completly redesigned console (housing midibox stuff, ad/da shiz and a reworked mixer config) so the original brds will no longer be able to fit within the new design anyways...
Props!
D
I'm wondering what to do EQ wise for that MC2404 desk i picked up and mebbe this design could be good?...what do u rek?
I've striped the whole thing (was pretty messy n tatty neways - was only 80 quid afterall ;p) and looking at the brds they are chok fulla carbon resistors, ceramic caps and moody opamps - i dont think modding the brds themselves is feasible anymore as I'm already gonna be using the panels/frame for a completly redesigned console (housing midibox stuff, ad/da shiz and a reworked mixer config) so the original brds will no longer be able to fit within the new design anyways...
Props!
D
Svart
Well-known member
have you tried anything else besides the LM833? if i'm not mistaken that is considered a comparator, which is usually less than audio quality right?
I swear by the opa404 now, and i like the MC3309( i think that's the right part#) in the EQ too.
:guinness:
I swear by the opa404 now, and i like the MC3309( i think that's the right part#) in the EQ too.
:guinness:
NewYorkDave
Well-known member
Would this "relatively common portable mixer" be a Soundcraft?
The schematic fragment you posted looks like their style.
The schematic fragment you posted looks like their style.
y0!
yup, thought about this too - Peter P mentioned it in a cpl threads with some additional mods - just waiting to see how he gets on widit... I'll do the same to see how goes with this one n all then... soz for not bringin any 'know-how' to the table tho :grin:
Cheers!
yup, thought about this too - Peter P mentioned it in a cpl threads with some additional mods - just waiting to see how he gets on widit... I'll do the same to see how goes with this one n all then... soz for not bringin any 'know-how' to the table tho :grin:
Cheers!
There's an interesting blurb on that site about simulated inductors using an opamp. I haven't seen that before. Is this something that's commonly done?
You'll have to forgive me, my DIY delving has primarly consisted of mic pre and compressor work. I'm nearing completion on the compressor rack, and also the mic pre rack, so am starting to look into EQ's =)
Regards
ju
You'll have to forgive me, my DIY delving has primarly consisted of mic pre and compressor work. I'm nearing completion on the compressor rack, and also the mic pre rack, so am starting to look into EQ's =)
Regards
ju
NewYorkDave
Well-known member
Yep. Such simulated inductors are known as "gyrators."
ok, so that turns on some light bulbs. :idea:
How do these gyrators compare to passive inductors? Say I were to build the pulteq eqp design, only with a gyrator and stepped attenuator providing the inductor values.
comparable, or a different beastie altogether?
Regards
ju
PS. Sorry to take this on a tangent, but we haven't started talking about food yet :grin:
How do these gyrators compare to passive inductors? Say I were to build the pulteq eqp design, only with a gyrator and stepped attenuator providing the inductor values.
comparable, or a different beastie altogether?
Regards
ju
PS. Sorry to take this on a tangent, but we haven't started talking about food yet :grin:
> the LM833? if i'm not mistaken that is considered a comparator
No, LM833 is National's reinterpretation of the 5532, and is a prefectly good audio amp. Maybe not quite up to the 5532, or maybe just never caught-on the same way.
You may be thinking of LM339, which is a cheap comparator, won't even work in most opamp circuits.
> the LM833 is the dual version of the LM837 IIRC.
They are not quite the same. Not different enough to matter.
> redesign the EQ enough that it is usable
I'm unenthused because what you have is a hell of a lot more EQ than I ever needed in live performance, and I don't get how it can be not "usable". Yes, I have used some "magic" EQs, but I don't think you get there by random mods of an ordinary EQ.
And I've often found that bypassing (not just centering) the EQ stage works wonders.
Have you run response sweeps? I'm too analytical, but when random mods fail, some analysis may show you what you are not hearing.
No, LM833 is National's reinterpretation of the 5532, and is a prefectly good audio amp. Maybe not quite up to the 5532, or maybe just never caught-on the same way.
You may be thinking of LM339, which is a cheap comparator, won't even work in most opamp circuits.
> the LM833 is the dual version of the LM837 IIRC.
They are not quite the same. Not different enough to matter.
> redesign the EQ enough that it is usable
I'm unenthused because what you have is a hell of a lot more EQ than I ever needed in live performance, and I don't get how it can be not "usable". Yes, I have used some "magic" EQs, but I don't think you get there by random mods of an ordinary EQ.
And I've often found that bypassing (not just centering) the EQ stage works wonders.
Have you run response sweeps? I'm too analytical, but when random mods fail, some analysis may show you what you are not hearing.
Hey Butta....
I'm gonna reuse the exsisting faceplates - luckily my alps motorfaders fit the slots and drill holes, and I'm reusing the switches for midibox controls (just had to remove a lil mechanism thingy inside so they work with momentary action), other then that everything else more or less fits to a standard 2.54mm grid so I can make new brds pretty swiftly
Will have to get some drilling/dremel action goin tho for the master/monitor/transport section...
I need start takin pics and chronicle the project along the way!
Thanks for the edz'up on the Amek at jakobs site - more eq'age to ponder on! :thumb:
Peesh!
D
I'm gonna reuse the exsisting faceplates - luckily my alps motorfaders fit the slots and drill holes, and I'm reusing the switches for midibox controls (just had to remove a lil mechanism thingy inside so they work with momentary action), other then that everything else more or less fits to a standard 2.54mm grid so I can make new brds pretty swiftly
Will have to get some drilling/dremel action goin tho for the master/monitor/transport section... I need start takin pics and chronicle the project along the way!
Thanks for the edz'up on the Amek at jakobs site - more eq'age to ponder on! :thumb:
Peesh!
D
sorry to throw sticks in the henhouse... but how does a 2500 eq compares to something like an analog Mackie eq?
I'm also considering some upgrades for my daughters studio
the 2500 doesn't look to expensive in components.
Would a Calrec eat the 2500 for breaky or is it just another type of beast?
Thanks for feeding back
Buttachunk, do you ever sleep? :shock:
:guinness: :sam:
Tony
I'm also considering some upgrades for my daughters studio
the 2500 doesn't look to expensive in components.
Would a Calrec eat the 2500 for breaky or is it just another type of beast?
Thanks for feeding back
Buttachunk, do you ever sleep? :shock:
:guinness: :sam:
Tony
[quote author="buttachunk"]
ha ! i'm powered by Red Bull at the moment-- been going through a 4 pack per day recently :thumb:[/quote]
Been there, done that :green:
you've got my 2500-lust awoken,
Take care my man and don't forget to party tonight, maybe a Sixpack RB?
ha ! i'm powered by Red Bull at the moment-- been going through a 4 pack per day recently :thumb:[/quote]
Been there, done that :green:
you've got my 2500-lust awoken,
Take care my man and don't forget to party tonight, maybe a Sixpack RB?
Svart
Well-known member
Thanks PRR you were correct, I WAS thinking of the lm339, not the 833. Sorry, I've been on too much cold medicine as of late.
:guinness:
:guinness:
NewYorkDave
Well-known member
Another good gyrator-based EQ is the Orban 622. I have one, and it's a great all-around tool.
Manual w/schematic and theory of operation available here
Manual w/schematic and theory of operation available here
> gyrator-based EQ ...the Orban 622
Oh, what a sweet classic.
Non-reciprocal.
One special function is near infinite nulls. Not musical, but helps save flawed recordings.
Wait a sec: it must be garbage. Look at all the 4558 chips!
And (to be strict) it isn't a gyrator. It is two allpass phase shift networks with positive and negative feedback. Real brain-twister.
And a major pain to duplicate. Lots-o-parts, and some fussy trims.
Oh, what a sweet classic.
Non-reciprocal.
One special function is near infinite nulls. Not musical, but helps save flawed recordings.
Wait a sec: it must be garbage. Look at all the 4558 chips!
And (to be strict) it isn't a gyrator. It is two allpass phase shift networks with positive and negative feedback. Real brain-twister.
And a major pain to duplicate. Lots-o-parts, and some fussy trims.
Damn it Butt Chunk,
Just when it was getting interesting :sad:
Okay___I'm going to spill the beans.
I want to build a small format inline console utilising a modded "green" front end followed by a basic 4 band para or maybe semi para or maybe shelving & hi/low & semi par mids of which the design would be created from a stripped down version of the Calrec & now Chunk you've introduced me to the MCI & the Amek 2500! Decisions, decisions!
Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaagh!
Mmm! That feels better!
So this thread was right on track for me.
Butta & everyone please don't let this thread slide off into obscurity?
Regards,
Danielle
Just when it was getting interesting :sad:
Okay___I'm going to spill the beans.
I want to build a small format inline console utilising a modded "green" front end followed by a basic 4 band para or maybe semi para or maybe shelving & hi/low & semi par mids of which the design would be created from a stripped down version of the Calrec & now Chunk you've introduced me to the MCI & the Amek 2500! Decisions, decisions!
Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaagh!
Mmm! That feels better!
So this thread was right on track for me.
Butta & everyone please don't let this thread slide off into obscurity?
Regards,
Danielle
Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaagh!
Now the NEMEK :shock:
Well I 'spose you have to put Rupe first Keef___ MEKNEV doesn't have quite the same ring to it.
You changed the thread title butta! Sneaky!
Sorry to hear about your blowup. Bloody ribbon cable
It's a cost efficient way to wire up a console but___I think you get my drift?
Regards,
Danielle
BTW: What software are you drawing your schems up with?
Now the NEMEK :shock:
Well I 'spose you have to put Rupe first Keef___ MEKNEV doesn't have quite the same ring to it.
You changed the thread title butta! Sneaky!
Sorry to hear about your blowup. Bloody ribbon cable
It's a cost efficient way to wire up a console but___I think you get my drift?
Regards,
Danielle
BTW: What software are you drawing your schems up with?
