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I’m in the process of building a PA for DJ use that will largely have analogue signals sources played through it. Given that our crew really only plays vinyl with the occasional digital effect unit, the purist in me wants to maintain an analogue signal path from source to ear. The plan for the system is to start with a pair of Tuba 30s for the subs and some Nady cabs (PTS 515 – single piezo horn + 12 woofer) and then replace the Nady set with OmniTop 12s and an additional set of Tubas.
I know you guys seems to be hot on the DBX driverack pa2 and other all-in-one speaker management systems but if you were to go analogue, what would recommend for the compressor/limiter, the crossover, and the Eq? Is there anything else that the PA2 does that strikes you as critical that I should consider?
Best,
Jacob

Going full-analog signal path makes no sense anymore. Use AD converters right after the turntables, and never look back. Gives you the touch of vinyl with the control, clarity and manipulation of digital.

So what you're trying to do is add distortion at every turn?

Here's the deal. If you're using any tops other than high end studio monitors, you are already coloring the sound beyond the point where it matters. Analog processing will just add unwanted noise and color to that. Use a driverack, and get a small digital console if you can. As much of a Behringer hater as I am, I have an X18 for small gigs, and it sounds great. The XR12 is smaller and has the same processing. Spend your money on a good Pre for the turntables.

I appreciate the advantages of an all digital setup and I'll take a look at the XR18 but we've already got a small board and there's a lot of the analogue gear on the used market cheap which I must admit, is also coloring my thinking/signal path (ha). Any advice on which pieces of analogue gear, current or older models, I should be looking out for?

As for getting a separate phono pre, the Apt Holman pre I have for my stereo is excellent - perhaps I'll swap that into the signal path before my mixer and see what difference it makes...

Many thanks,
j

tactix wrote: there's a lot of the analogue gear on the used market cheap

There's a reason for that. Not only does digital work better, you need a lot less of it when all the effects you might need are on the board, and a loudspeaker management system can do crossover, EQ and limiting all in one package.

DBX PA2 also has a RTA function which does a pretty good job, but most of times I adjust the automatic made setting by hand to get a nicer curve. I use a Behringer EMC8000 rta mic with it, which was even cheaper in earlier days.
I love this device and it's easy setup and adjustments, by app via laptop, phone or tablet over wifi or a network cable.

Very much agreed about the XR18 and the PA2.

I can't sing the X-Air line's praises enough. They sound phenomenal when in good hands, and are incredibly versatile.

For your needs, I'd suggest an XR12 ($250 new) or an MR12 ($450 new. Same device but with upgraded preamps, ADCs, and DACs). If you need more than 4 mic inputs, move to the XR18 ($600), X18($450), or MR18($880). Skip the 16. It isn't worth it. If you ever need to play from or record into a PC, go straight to the 18. It has a USB input that bypasses the crappy DACs in most laptops. Highly recommended.

The Behringer X series has a 3 year warranty iirc. The Midas versions just implemented a 10 year warranty (stuff in the retail channel won't say it on the box, but it's been applied retroactively)

The mic/line preamps are digitally controlled, but are analog. After that, it goes straight into the ADCs, and from there all processing is done in 24 bit 48 KHz floating point. No additional analog stages, no spots for extra hiss to creep in, no generation losses. Then it goes to a DAC and back into the analog world. So, the only spots hiss can creep in are the preamp, ADC, and DAC. With analog gear, everything is a hiss possibility, plus every device can add distortion.

Each channel has its own 100 band RTA and 6 band parametric EQ overlay. Each channel has its own compressor and gate, too. Each output has its own 100 band RTA and selectable 31 band graphic EQ or 6 band parametric. There are also 4 effects busses (many stereo effects can be used as dual mono), including a huge selection of really awesome effects plugins. I've found the reverb, subsynth, and amp modeling to be very useful. Many swear by the multispectral compressor.

The X-Air's built in wifi is a joke. Make sure to get a good dual-band router. Password your wifi, use ethernet whenever possible, and if you must use wifi, try for 5GHz over 2.4 GHz.

The X-Air Edit software for PC and Mac are absolutely awesome. The Android and iOS software isn't as awesome but is still quite good.

From there, go out to a DBX DriveRack. I've been using a PA2 ($400 new, but you need an RTA mic for $60 to $100) and adore it, though it does add a bit to the noise floor. I've got a Venu360 ($800 new) ready to go, but I haven't had the opportunity to test the noise floor yet. The PA2 software is a lot more complicated, but it has 3 inputs, so you can use the 3rd for monitors or sub on aux if you need it.

The DriveRack is critical for a bunch of reasons:

• The Auto EQ using the RTA mic is a fantastic tool for getting the venue sounding decent. Tone it out, then EQ to ear.
• Crossover. 'nuff said
• HPF. Use it to limit the low bass going to your subs. No point in reproducing super low frequencies if it isn't musical content. Especially if you're using vinyl - lots of rumble artifacts there.
• Brickwall limiter. Invaluable for protecting your subs.
• Automatic Feedback Control - very useful for the unexpected, but you'll sound better with someone at FOH listening and adjusting without it.
• Subsynth - I've found it useful for adding some texture to pre-recorded music. If you like it, play with the subsynth built into the X-Air. A lot of people (especially purists) hate this one, and its easy to get into trouble.
• Time alignment - make your bass and your treble arrive at the same time. Very important.

The PA2 and Venu360 also have awesome PC control software. The Android software is unreliable, alas. I've not tried the Mac/iOS software, but I'd expect it to mirror PC/Android.

Both the X-Air and Driverack series retain their settings when powered down, so setting up the same or similar gigs is a breeze. Just pick up where you left off.

Once you've gotten used to the ability to walk around and control from anywhere, there's no going back. =)

Great to read that Alexk, XR18 was allready on my list.


I only paid €220/$250 (2nd hand) for the PA2 and €38/$44 for the mic (new). Best buy ever! But the Behringer X Air XR18 is €689/$792 over here, hopefully we get a price drop soon.

Even 700 euros is a steal for an XR18 (or X18). 10 years ago, that would have been over 10,000, taken up a couple of racks, and not sounded nearly as good.

alexk wrote:Even 700 euros is a steal for an XR18 (or X18). 10 years ago, that would have been over 10,000, taken up a couple of racks, and not sounded nearly as good.

It sure is!
But I don't need it right now and the X18's price is allready down to €515/$592, still quite a difference in price, so I will wait at least some months. If I would need one now, I would ask a friend om mine to buy it in the USA and take it back in her suitcase or mail it.

// and other little behringer gem is the Xenyx302USB USB powered, usb soundcard/dac and mixer with mic in. Used it for years outdoors (no need for AC was the feature why I bought it) and it is used 24/7 for years now at my pc in my living room otherwise.
It is very versatile and compact (4"x6") and keeps on going like the day I bought it.

Thank you all for your insights and suggestions. You've given me a good sense of what the advantages are of a digital system. A tablet only driven system is not going to work for my crew - the immediacy of being able to see the leds peaking and being able to make adjustments with pots and slide faders is important. The noise and distortion question is well taken but I can live with a bit of that if it means everybody being able to see what's going on and be able to make adjustments. It may very well be that the feature set in the driverack will outweigh all other considerations and maybe there is one is in my future. It will depend on what I can find used. I already have a mixer though the X18 does look pretty great. The question I'm asking myself is what it will it cost for a decent crossover + limiter + eq vs driverack.

tactix wrote: I'm asking myself is what it will it cost for a decent crossover + limiter + eq vs driverack.

I just saw a used Driverack PA+ on CL for $100......I almost picked it up myself, but I already have 3 in use and 1 spare..... yeah, I like 'em.

And you can use the original PA, PX, or PA+. They are pretty cheap on the used market.

tactix wrote:... The question I'm asking myself is what it will it cost for a decent crossover + limiter + eq vs driverack.

More and you won't have RTA or the usability of the DBX PA2; setting it up by pc or tablet is great and MUCH easier and makes your settings visual.
The day I decided I wanted to have the PA2, I found one for €220/$250 2nd hand but as new, so it was a no brainer for me. Even €400 for a new one over here is still the best buy by far.

The older DriveRack PA+ is also fine and misses mainly the easy setup and control by pc or tablet.

tactix wrote: Is there anything else that the PA2 does that strikes you as critical that I should consider?

It's a little late into the discussion, but yes there is something critical the units like the driverack series, the DCX2496 from Berry, and the other players in the market for DSP do.

It's the "brick wall" limiting capability.
Brick wall limiting allows you to set a value that prevents your amplifier giving your (in your case T30's) subs to much voltage, which leads to blown drivers.

And, because it does that, such units are mandatory, not desirable, when using Bill's sub designs.

Why do you need that? Look at "protecting your drivers" in your plans.

Brick wall limiting is somewhat different to a standard compressor/limiter (such as may be used as an insert over vocals, kick drum, overall mix), so those types of units shouldn't be used to try to brick wall limit. Compressor/limiters obviously have a limiting function, so this tutorial is one way to explain the difference:
https://music.tutsplus.com/tutorials/a- ... audio-1071

If it makes you feel more comfortable with the idea of using DSP's like those listed above, the only place the signal is digital is within the unit itself. Straight from the input side, the signal is passed through an ADC (analogue/digital converter) and after all the magic is done, just before the output side, the digital signal is converted back to analogue via a DAC.
So, for all intents and purposes, the signal path remains analogue...

Grant Bunter wrote:

tactix wrote: Is there anything else that the PA2 does that strikes you as critical that I should consider?

It's a little late into the discussion, but yes there is something critical the units like the driverack series, the DCX2496 from Berry, and the other players in the market for DSP do.

It's the "brick wall" limiting capability.
Brick wall limiting allows you to set a value that prevents your amplifier giving your (in your case T30's) subs to much voltage, which leads to blown drivers.

And, because it does that, such units are mandatory, not desirable, when using Bill's sub designs.

Why do you need that? Look at "protecting your drivers" in your plans.

Brick wall limiting is somewhat different to a standard compressor/limiter (such as may be used as an insert over vocals, kick drum, overall mix), so those types of units shouldn't be used to try to brick wall limit. Compressor/limiters obviously have a limiting function, so this tutorial is one way to explain the difference:
https://music.tutsplus.com/tutorials/a- ... audio-1071

Thanks for your thoughts on this and the link Grant. So yeah there are analog peak/brickwall limiters out there from the likes the Aphex or dbx but they're another piece of specialty gear to track down (the Aphex Dominator II 722 looks decent) and aren't that cheap. I don't think it's possible, used or new, to put together an analogue solution with the same functionality as the driverack units for a comparable price but it seems like an analogue only solution is to be had if you want it. At any rate your comments have made it clear that I'm not going to be able to use just any old limiter here. I appreciate the input.