Calrec PQ1549 Equalizer - is it good for a DJ mixer?

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

cheater

Member
Joined
Oct 6, 2005
Messages
11
Hi guys,
I'm looking to DIY a DJ mixer, since nothing I know can really satisfy me :)

To start off I'm looking for an EQ with 3 or (prefferably) 4 bands, which could totally (totally! -36dB :) ) cut out the bands.
Something like the Pioneer DJM600 EQs, or the Vestax DCR-1200 Pro.

I've been pointed to this EQ, and this EQ's "website" (as it's, of course, not the official website) - http://gyraf.dk/gy_pd/calreq/calrec.htm - points to this forum in case of questions.

So,

can anyone tell me if this EQ can cut out bands like that?
If not, can someone recommend any EQs I might be able to build on my own? :)

cheers,
Damian
 
...Do you know what "Bands" are? -You don't write like you do. -Actually, can someone tell me what 'bands' are?

-Sorry if this is an obtuse reply, but the post sounds like you don't know what you want. It also sounds like you've never used this type of equipment before. -There are planty of EQs that can be cascaded on the same frequency if that's what you mean. It's just about the last thing they'd ever get used for.

Will it make you happy? -build it and see.

Keith
 
With "bands" i mean each of the ranges represented by each of the gain knobs, shelf/band-pass filters, etc.

No reason to get upset at me.

As said, it's going to be put in a dj mixer, in a live setup situation. I'm totally not going to cascade EQs there. The mixer would end up being bigger than a mellotron for a five-track stereo set up, and also, it'd be unstable, especially since temperatures in clubs range from +8 celsius at winter (don't ask) to +40 celsius mid summer.

Judging from your post,
perhaps you've never used one of the EQs I've listed.

They're not your usual run of the mill mastering equalizers.

They have steep cut-off while maintaining little to no resonances/ringing/oscillation at even the biggest gain increases/decreases. Can't say this happens with typical filters.

Sorry to be welcomed like this :? I'm sure others here don't newb-bash random people, though :roll:
 
I would call the Calrec a typical mastering type EQ. The cutoffs are not particularly sharp and the cut/boost is only +/-15 dB IIRC. It sounds like you need something with higher order filters and more range than the Calrec.

-Chris
 
Sorry to be welcomed like this :? I'm sure others here don't newb-bash random people, though :roll:
Possibly not, but then your post's phrasing does imply a lack of experience. -I could be wrong, of course.

What ones have I used? -Well, plenty. I used to build SSL retrofit equalisers, I've used pretty much every EQ that is respected or talked about... possible exceptions I can immediately think of being the Sontec and the Klein & Hummel. This morning I was working with a pair of Massenburgs, a LaFont and a BSS DPR-901. On my bench at home I have a pair of UREIs and I have a cupboard full of UREI graphics... ( :roll: ) I've got some AMEK 2500s at home, several different SSL EQs and some Neve clones which I knocked together...

I started work on a PCB layout for a "Ne-MEK" (part Neve/Part AMEK) but I've not had the time to finish it.. the only intention with that is to share freely with everyone, I'm not into trying to sell it. That's actually interesting because the High and low bands when in shelving mode have a variable entry slope, with the knob which forms the 'bandwidth' control changing function. (all 'shelving' is infinite bandwidth after all!)

We've got a couple of hundred channels of 9098i EQ here. The mid bands on those are switchable to notch, with either a ± up to18dB or a -90dB setting. The uses are specific, but limited. Nicely designed system though.

The Calrec is a project I recommend for many people. Try it. You might even like it.

Adjusting the value of the four 5k1 resistors (along the summing chain at the top of the schematic... one from the output of each filter, feeding the signal into the summing chain, each is near to the cut/boost pots , IIRC) will allow you a ±range of pretty much whatever you choose. Reduce value for more range, increase for less range. Background filter band noise will increase with range.

Keith
 
Emperor-TK: Thanks! Any pointers to nice EQs fit for my purpose, then?

SSLtech: OK, cool, but your dozens of EQs are probably useless for me, since, again, this is a DJ environment we're talking about. Remember that -18 dB of cut is nothing when people are standing 2 meters in front of 2000W of power.

This is why the DJM600 and the Vestax mixers are so popular among DJs.

I will definitely try the calrec down the line. But enhancing my studio isn't my focal point right now, and probably won't be for a year or two...

cheers,
D. 8)
 
[quote author="cheater"]Remember that -18 dB of cut is nothing when people are standing 2 meters in front of 2000W of power.[/quote]
...Boy... -Is THAT ever flawed thinking!

18dB is a multiplication (if positive, or division if negative) by a linear voltage factor of 8, at any power... a division of linear power by a factor of 64. 2000 Fully driven watts becomes 31-point something Watts when you take away 18dB.

I definately get the impression that you THINK that you understand more than you actually do...

Keith
 
[quote author="cheater"]Emperor-TK: Thanks! Any pointers to nice EQs fit for my purpose, then?[/quote]

I'm not really too up on that kind of stuff, but have you looked at any of the discontinued Electrix stuff, filter factory, filter queen, etc? I seem to remember some of this stuff having "band cancel" type filters.

-Chris
 
Perhaps.


But I have the advantage of hands-on experience in that field.

Do you?

I'm not talking about sitting in a studio.

Please, stop attacking what I say, as I know what I'm doing, I've done it a few times with success.
 
[quote author="Emperor-TK"][quote author="cheater"]Emperor-TK: Thanks! Any pointers to nice EQs fit for my purpose, then?[/quote]

I'm not really too up on that kind of stuff, but have you looked at any of the discontinued Electrix stuff, filter factory, filter queen, etc? I seem to remember some of this stuff having "band cancel" type filters.

-Chris[/quote]

Ahhhh yes! Very good ones indeed. :thumb:
I tried to find schematics for so long. But failed miserably ;)
 
Hey cheater,

A cheap rackmount Benrhinger x-over can filter at -24db per octave slopes... It probably can reach those resonance FX frequencies you talk about... might be worth experimenting with.
 
Hi Damian,

This forum is a special place with a lot of well respected members from the pro-audio world. I myself am a mere leecher on this forum who loves to build and use good sounding equipment with a vintage flavour and are very grateful for the work of these guys.
To give you an idea to how crazy some people get:
right now I don't have any money, am in desparate need of a new pair of shoes, but I would also like to get some discrete Forsell opamps to build his compressor.. No suprise where the cash is gonna go... who needs shoes anyway.:green:

So if people act a bit weird and grumpy don't take it to seriously, check out the posters other posts and discover he's a smart and ok guy!:cool:

About the Calrec, I've built one and like it very much. You could use it for live DJ-ing because it is capable of radically altering the sound and pretty extreme cutting and boosting but it's probably not what you're looking for.

First of all, the mixers you mention use fixed frequencies for each band and have only one knob for boosting or cutting.
The Calrec uses two knobs per band, one for boosting and cutting and one for setting the frequency. This means that you can sweep the cut or boost frequency by twisting this knob.. this creates a very nice wha-wha kind of effect but is probably not the effect you want.

Secondly, because the bands on the Calrec don't have a fixed frequency, the band-range is probably not wide enough for the kind of stuff you're looking for. You can't cut all of the lower or higher mids for instance.. Only a certain area centered around the chosen frequency. There is even a knob to narrow the bandwidth some more (high q setting).

If you're going to use your eq for producing music as well as DJ-ing I would definitely recommend you build the Calrec, because it sounds great and is pretty easy to build..
For DJ-ing only I would recommend you try something else..

Adios,
Corneel
 
Yes I do. On systems much bigger than that.

I'm not really 'attacking', my primary aim is to make sure that you understand what these things do. -You did come here looking for information and advice, right? -Here's some first-rate, reasonably well technically qualified, reasonably well experienced advice.

It matters not how loud or powerful a signal is, any given number of dB gain change is still the same sonic change.. no matter how much you turn it up or down.

I'd say that Vestax sell well because of the price. Most modern EQs can be modified to do do any amount of boost and cut; That's not what makes it good.

It's really the way you qualify or explain your reasoning behind your thought process and/or decisions which keeps triggering my urge to correct you. If you want to make decisions based on hype, it's easy to read promo material. If you want to make decisions based on understanding, you need to understand. I'm assuming you want to understand, or I won't bother correcting any other misconceptions.

No biggie.

Keith
 
Emperor-TK:
Thanks a lot! I didn't know they resumed building those boxes.

Still, $150 seems too much for something I may or may not be able to reverse-engineer... and $150x5 isn't an option for me :wink:

jetboatguy:
interesting. I never thought about looking at crossovers. I should give it some research time :)

Nele:

the shoes... oh tell me about it :) still remember balancing 12-hour night-time recording/mixing/mastering sessions with studying maths and wearing those (those are my fingers in there) :)

I do know how forums like these work... but you'd need a lobotomy to always be able to bear all that stuff.

Indeed the added crossover frequency is a plus, but that's not really *totally* necessary. However, it's still very good for isolating instrument lines etc.



SSLtech:

of course it's the same sonic change.
However, it's the same sonic change.. in respect to what?

The problem I see is:
at -18 dB, if I turn everything down, after 2-3 seconds people will get accustomed to the low level and will start hearing what's supposed to be "cut out". (this is why I assumed at once that you didn't know much about DJ performances - as this is a typical technique/problem which every DJ should know)

If the sound is cut out more, it'll take them more time. Enough time for me to follow up with some action.

Also, we're talking about cutting out the whole band. Not just the frequency centers.
That's what Emperor-TK pointed out to me - that we're talking about steep cut-off characteristics (and that the Calrec has a much too high filter quality factor for this).
Having said that, I think (?) you can assume that a fixed-Q-factor equalizer which can go to -40 dB can have a much steeper cut-off curve than one that goes only to -18 dB.
Sure, I could go full-on and make an EQ out of several 48 dB/oct filters. But it'd be like re-designing the wheel.
Besides, making it work flawlessly would probably be too hard for me, as I'm definitely not an electronics god :)

Still, thanks for your willingness to help. Skin of stone heart of gold, as they say ;)

With all of that I've written, bear with me, and do correct my mistakes. Constructively, please!
 
Hey Keith,

Get busy and finish up your 'Ne-MEK' project. I had forgotten about that one. I had thought that one to be especially interesting when you spoke of it before. So finish it up, please??
 
[quote author="cheater"]
The problem I see is:
at -18 dB, if I turn everything down, after 2-3 seconds people will get accustomed to the low level and will start hearing what's supposed to be "cut out". (this is why I assumed at once that you didn't know much about DJ performances - as this is a typical technique/problem which every DJ should know)

If the sound is cut out more, it'll take them more time. Enough time for me to follow up with some action.

[/quote]

Kieth, I think is the root of the disconect here. I think I am correct in assuming that he will be riding the EQ in real time for effect. Drop the mids, put them back, drop the bass, put it back, do a filter sweep of a drum loop....and on into the night. Cheater, I think that you needed to clarify that point. This is EQ being used as a DJ effect. What Cheater is saying above is that if you don't get rid of ALL of the midrange when you drop the mids, the audience's ears will compensate too quickly and the effect won't be intense for very long. That's why he wants such a drastic EQ, and thats why Electrix made one.

-Chris
 
Sure...

I'm packing for AES at the moment and I'm a bit grumpy... forgive me all!

Cheater, there's some truth in the math behind my grumpiness, so at least it's not all negative! :wink:

Yes, all the EQs using band-pass filters of this type (amek 2500/Neve V and 'formant' types/Calrec amongst others) i.e. all the ones using state-variable filters, and sould exhibit similar bell shapes and phase response behaviour. if you want band-reject or bandstop, they all have a drawback: they only have a narrow center frequency where it's at full dip.

The Electrix pro ones generally tend to use state variable also, but just not in bandpass, from those I've seen; they use HPF and LPF state-variable also, and these in combination can be used to mimic wide and deep bandstop.

I suppose I'd suggest that you try some of their stuff if you're after wide and deep band-rejection. They tend to make things rugged, lightweight and staggeringly affordably. their "Filter Factory" can also do a randomised sample & hold to drive a Voltage-controlled state-variable filter, and this can do the effect best remembered at the start of Emerson, Lake & Palmers "Carneval #9" (you know, the sound that fades in before the line "Welcome back my friends to the show that never ends..."etc.)

For that money, I'd say don't even attempt DIY. -I don't know for sure ifthey can be linked for stereo use (should be possible, -they're voltage controlled after all. -If there's no such facility, buy two and modify the second to be a slave to the voltage control of the first... that'd give you something nobody else would have!)

You can pre-set a filter, switch it out & in, tap tempos, MIDI control... hell, I couldn't build you a decent single channel calrec for what those things can do.

Seriously... -try it! Money back guarantee! :wink:

Okay, Welcome properly now... :green:

Keef
 
[quote author="Emperor-TK"]
Kieth, I think is the root of the disconect here. I think I am correct in assuming that he will be riding the EQ in real time for effect. Drop the mids, put them back, drop the bass, put it back, do a filter sweep of a drum loop....and on into the night. Cheater, I think that you needed to clarify that point. This is EQ being used as a DJ effect. What Cheater is saying above is that if you don't get rid of ALL of the midrange when you drop the mids, the audience's ears will compensate too quickly and the effect won't be intense for very long. That's why he wants such a drastic EQ, and thats why Electrix made one.
-Chris[/quote]

YESS!!

[quote author="SSLtech"]
Sure...

I'm packing for AES at the moment and I'm a bit grumpy... forgive me all!

Cheater, there's some truth in the math behind my grumpiness, so at least it's not all negative! :wink:
[/quote]
A maths student will always fish out the good tidbits. You're right :grin:

Yes, all the EQs using band-pass filters of this type (amek 2500/Neve V and 'formant' types/Calrec amongst others) i.e. all the ones using state-variable filters, and sould exhibit similar bell shapes and phase response behaviour. if you want band-reject or bandstop, they all have a drawback: they only have a narrow center frequency where it's at full dip.
I guess that's what I should have been asking in the first place :roll: :grin:
The Electrix pro ones generally tend to use state variable also, but just not in bandpass, from those I've seen; they use HPF and LPF state-variable also, and these in combination can be used to mimic wide and deep bandstop.

I suppose I'd suggest that you try some of their stuff if you're after wide and deep band-rejection. They tend to make things rugged, lightweight and staggeringly affordably. their "Filter Factory" can also do a randomised sample & hold to drive a Voltage-controlled state-variable filter, and this can do the effect best remembered at the start of Emerson, Lake & Palmers "Carneval #9" (you know, the sound that fades in before the line "Welcome back my friends to the show that never ends..."etc.)

For that money, I'd say don't even attempt DIY. -I don't know for sure ifthey can be linked for stereo use (should be possible, -they're voltage controlled after all. -If there's no such facility, buy two and modify the second to be a slave to the voltage control of the first... that'd give you something nobody else would have!)

You can pre-set a filter, switch it out & in, tap tempos, MIDI control... hell, I couldn't build you a decent single channel calrec for what those things can do.

Seriously... -try it! Money back guarantee! :wink:

That's the thing...
I'd want 10 of them in a mixer..
Not only would they be cumbersome (big cases, and warranty void if I take them out), they would be very bad to implement (hacking them like that isn't giving me the best feelings about it!)

Alternatively, IF I learn how to make those, I'll end up throwing these in everything I have/I will build/etc

As for the midi stuff: check out http://www.ucapps.de - they're real good!

the S&H - I've never heard (of) the song you mean, but I guess you just mean a low-frequency S&H routed to the cutoff and/or resonance of a LPF?

BTW the electrix filter sounds just like a normal moog filter, albeit the mp3s on their website are too lo-fi to tell exactly :wink:

Okay, Welcome properly now... :green:

Keef

Thanks, thanks a lot :) :thumb:
 
Back
Top