Peavy IPR DSP amp and the MaxxBass effect

[Jeff]

My current setup:

2 - JBL JRX115i’s tops
1 - JBL PRX418S sub
1 - DBX Driverack PX
1 - Crown XLS2500

I use this system for both my band and DJ work. I have been wanting a more authoritative low end for quite a while and have been browsing this forum looking for subwoofer ideas. I was leaning toward some Tuba45’s when I heard another DJ's system at a wedding last weekend that I was really impressed with.

His speakers were also JBL’s - not sure of the model numbers but very similar in size to my setup. I went to ask him about it and he said his secret was his amp. He was using a Peavy IPR DSP 3000 and it’s BassMaxx feature. He said it simulates low frequencies psychoacoustically. He had dance club type low end coming out of that setup and I was really impressed.

In the past I have seen discussions of the Peavy IPR amps, but never a mention of the MaxxBass effect. Does this work effectively with the BFM subs? Does anyone have any opinions or experiences with this effect?

[BrentEvans]

Waves Maxxbass adds a series of harmonic overtones to the bass signal making it seem "bigger" or "fatter." It is a form of controlled distortion, and it does alter the perception of bass. IMHO it's far more useful as a mastering effect than as an output process on your sub signal, though, as most of the harmonics it generates are not in the sub bandpass, and would get filtered right back out by the crossover (unless of course you use an external crossover, then the effect would sound like crap as it's not in the recommended bandpass of the subs).

I think Peavey put that effect in the IPRs to make them appeal to the MI and DJ markets, not becasue it improves the sound of anything.

That said... the IPR amps themselves are solid. I have eight... they work great.

[Frederic Gelinas]

I don't know how it is integrated in the Peavey amp, but I know the Waves MaxxBass effect. I use it in my home studio setup.

From Peavey's website:
"The revolutionary Peavey IPR Series DSP power amplifiers are the first to integrate Waves technology, in particular MaxxBass, which uses psycho-acoustics to create precise harmonic overtones that give the perceived effect of adding low frequencies to the mix."

The keyword is "perceived effect". What it does exactly in the Peavey amp is unknown, but my guess is that it removes the very low frequencies and add harmonics instead. The subwoofers that can't reproduce the original very low frequencies is now able to deliver the harmonics instead. The untrained ear will just ear some punching bass and won't notice the lack of low bass.

[Radian]

... most of the harmonics it generates are not in the sub bandpass, and would get filtered right back out by the crossover...

I was just going to say the same thing.

If anything, the effect would be of most benefit with a system employing very good tops (like DR's) and would involve the subs very little, to not at all.

*edit* For grammar

[CoronaOperator]

My current setup:

2 - JBL JRX115i’s tops
1 - JBL PRX418S sub
1 - DBX Driverack PX
1 - Crown XLS2500

You are really lacking in the subwoofer department. Your subs should be twice the size of your tops (ie: you need another one, for authentic club sound 3 more). For now, make sure you are familiar with wall and corner loading to get the most out of what you have. If your not putting your sub in a corner or next to a wall, you are missing out on 6-12 dB's of bass.

I was leaning toward some Tuba45’s ....... it’s BassMaxx feature .... He said it simulates low frequencies psychoacoustically ....... Does this work effectively with the BFM subs?

With Bfm subs and proper deployment of your system (wall loaded), you won't have to simulate anything, the real deal will be there.

[Jeff]

What is strange is that I can't find the user's manual for any of the Peavy IPR amps online at all - even the links to if from Peavy's own website are dead????

Using google search I stumbled upon this thread with people using the Waves MaxxBass (hardware version) with professional PA systems.

http://forums.prosoundweb.com/index.php?topic=105320.0

Particularly interesting was a comment in that thread about someone using it at a party at a museum and it gave the sound of massive low end response without making things in the room shake.

I also saw a comment that MaxxxBass on the Peavy IPR allows you to adjust it from "0 to 100%." The version of MaxxBass included with the IPR series amps doesn't seem to have all the adjustments available on the software or hardware versions available from Waves.

I have used the BBE and Aphex type "enhancers" before and they sound too synthetic for me. But the Peavy IPR MaxxBass I heard last weekend sure sounded good to me. I will have to try to contact that guy and see if I can get some more information out of him.

If anyone has one of the Peavy IPR DPS amps and some BFM subs, please give it a try and let us know what it sounds like.

[kkip]

Not a fan. I have done quite a bit of testing with the this feature on my IPR1600DSP which I have driving a pair of T-39s. To me it makes the clean clear bass notes sound muddy. In addition it adds a noticeable rise around 100-125 Hz making the system sound boomy. Another serious problem, is that the MaxxBass algorithm adds additional signal content. If you are relying on a limiter upstream from the amp, the output voltage is not going to be as well controlled since the amp no longer has predicable gain.

I've had similar issues with a Bag End Infra-mxb processor in my church. They had a sound company sell them a $35,000 system shortly before I started running sound there regularly. They installed a single compact sealed dual 18 sub for gymnasium sized hall and put a Bag End processor and a Crown XTI-4000 to drive it. Other than being too small for the room, it took me a long time to figure out why it was sounded so poor. Finally I realized that the sealed sub rolls off at 50 Hz and the Bag End processor adds a measurable rise at 125, just like MaxxBass. In comparison a national act, Building 429, played a concert in the same room. They used our flown array tops but brought in a sound company with 5 dual 18 sub cabinets for bass.