Sub amps with DSP (digital signal processing)

[Orbison]

Some current sub mfrs like Power Sound advertise that they have amps with DSP. Does anyone know if this actually improves a sub's performance? From PSA: "DSP amplifier is specifically programmed to produce an unsurpassed transient response to minimize ringing and one note bass"

Also, have the drivers themselves improved significantly in the last few years?

Very few test reviews available yet, so I'm curious....

I have an SVS PB12-NSD I got about 5 years ago. Chose that model for budget reasons at the time and it does quite well, but I'm not sure it's output is sufficient for the size of my room. However, aside from that limitation, Ikka's test review at that time indicated it would be hard to beat if compared to many of the newer models below $1K.

p.s. anyone want to contribute to my Triax fund? ray:

 

[Zing]

I'll be happy to contribute to your used SVS PB-12 NSD/2 fund by selling you the aforementioned sub (whose output will be more than sufficient for your room).

 

[Orbison]

Very kind of you Mr Zingster.

If you don't mind me asking why are you replacing it? Not enough oomph or just a bad case of upgrade-itus?

Why 2 subs? To balance out the response in your room?

 

[heeman]

Some current sub mfrs like Power Sound advertise that they have amps with DSP. Does anyone know if this actually improves a sub's performance? From PSA: "DSP amplifier is specifically programmed to produce an unsurpassed transient response to minimize ringing and one note bass"

Also, have the drivers themselves improved significantly in the last few years?

Very few test reviews available yet, so I'm curious....

I have an SVS PB12-NSD I got about 5 years ago. Chose that model for budget reasons at the time and it does quite well, but I'm not sure it's output is sufficient for the size of my room. However, aside from that limitation, Ikka's test review at that time indicated it would be hard to beat if compared to many of the newer models below $1K.

p.s. anyone want to contribute to my Triax fund? ray:

I am not answering you DSP question, however I bought my first sub in 2006; SVS PB12-NSD for the same reason you did, budget. I recently had multiple conversations with Tom from PSA, and decided to buy a XV15. Incredible increase in performance. Tom also indicated that, the PB12-NSD is no slouch at all. Not sure what I am going to do with it, however, recent conversations with Tom about running it with the XV15 may produce good results........ Good project for a rainy day, which never happens down here!!

My room is 12.5 w x 17.5 l x 8 h

 

[Orbison]

My room is about 14.5' wide by 21' long, avg ceiling ht about 10'. The back of the room has one large opening to the dining room, another to the entryway, and another to a hallway. The size of the room seems to be a good fit for my sub according to articles I've read, but the openings I mentioned (as well as the sub's performance) seem to indicate a bigger sub might be better. A little more oomph, ya know...

 

[Zing]

If you don't mind me asking why are you replacing it? Not enough oomph or just a bad case of upgrade-itus?

Why 2 subs? To balance out the response in your room?

I'm not the least bit dissatisfied with my sub's performance. It's upgrade-itis, plain and simple.

If I can get a smoother response, that'll be icing on the cake but, frankly, I'm going with two subs more so because of aesthetic symmetry.

 

[Orbison]

Zing - you might be interested in reading this article I found - pretty comprehensive info, 3 pages on sub setup. Much of it supports what we already know, but it goes into a more detail than what I've read before.

http://www.hifizine.com/2011/06/bass-integration-guide-part-1/

Too bad Soundhound's not around anymore. I'd like his input on my question about the newer sub amps & drivers.

p.s. Does your old sub come with hernia insurance?

 

[Flint]

DSP can be a hundred different things. It can be an EQ, a limiter, a frequency dependent limiter, a notch filter, a phase EQ,... hell, it can be almost anyhing.

 

[Zing]

Zing - you might be interested in reading this article I found - pretty comprehensive info...

That was a great read, Orb. Thank you. I will definitely refer back to it next week when my duals arrive. I found one thing odd though. It suggested "overlapping" frequencies to correct for dips/nulls. I've always been under the impression that if you have a null at, say, 90Hz, the last thing you should do is throw more 90Hz signal at it. :think:

p.s. Does your old sub come with hernia insurance?

No need. I have a hand truck. Plus it slides quite easily across carpet.

 

[Orbison]

Yeah, I wasn't clear on "overlapping" either. Not sure how you'd configure eqpt to do that anyway unless you set receiver to send bass to both the spkrs & the sub and then set the sub's XO higher than the spkrs..........

Anyway, my understanding is that (like you said) it wouldn't fix a null due to acoustics.

 

[Deleted member 133]

Two comments:

1. Heavy objects slide easily downhill (like from main floor down to basement) and fairly easily across level floors; but going up stairs really sucks!

2. Here's my wild guess for overlapping curves in that article: it introduces another controllable variable in the troublesome overlapped area. In other words you can now fiddle with two speakers (treating the sub and mains as one speaker each) instead of just one (the sub or the mains) at any given point where they're are both active. To a certain extent, that's one of the benefits of having multiple subs, and in my case, different types of multiple subs. (See my other postings about that.)

Jeff

 

[jamhead]

I'll be happy to contribute to your used SVS PB-12 NSD/2 fund by selling you the aforementioned sub (whose output will be more than sufficient for your room).

What color is the sub Zing?

 

[Batman]

I'll be happy to contribute to your used SVS PB-12 NSD/2 fund by selling you the aforementioned sub (whose output will be more than sufficient for your room).

What color is the sub Zing?

Black

 

[Tom V.]

Hi all,

For us, having a DSP frontend on an amplifier is a very good thing. First, all of your typical subwoofer filtering is handled in the digital domain. Compressors, (some)thermal feedback, EQing, attack, release, there's really dozen's of ways the signal is manipulated. When you do this in the analog domain you will often see issues because of signal saturation. An analog circuit reacting to 0.1v will give you a different result than an analog circuit reacting to several volts. Well, in this context it does.. When you have all of this processed in the digital domain the only real limitation is the sample size(your processor can handle).

Another key benefit is development time. During the initial proto-type stage instead of working with some sort of clunky analog board with resistors, diodes, mosfets(or whatever) all being soldered in/out in a very time consuming process of trial and error...you walk over to your laptop and work up any change you can imagine...all done in real time on the PC. What used to take days(or even weeks----depending on the weather is now done in minutes or hours. And there is a level of accuracy in the digital domain that you'll never approach in analog.

Lastly, you can spend a *lot* of time coming up with a driver improvement. With an all analog frontend, it may take quite a while to get everything back to *0* and you may find yourself so stuck in different areas that you start to compromise the driver improvements themselves just to get the design back to "bullet proof". With DSP, you are talking minutes and with an infinite amount of adjustability...you can always(ime) get maximum performance from the driver(s).

Also, if you can program the amps at the "shop" like we can....you can reduce inventory costing substantially as you can often use the same amp in two closely related products(like the XS15 and XV15 for example). Same amp, just a different DSP program..

The downside? Well, there is a learning curve to all of it. This isn't like setting the DSP on a consumer grade piece like a Behringer amp. Some of it is intuitive, some is anything but. Cost is probably the biggest hurdle for many OEMs. I can't get into specific pricing per amp but a DSP version will generally cost you 50-75% more depending on the amplifier manufacturer and the DSP capabilities.

Tom V.
Power Sound Audio

 

[Orbison]

Thank you Tom