Buying power amp- do I need DSP or no?

[SeayBass]

So I'm buying a power amp. Can yall help me to understand DSP and why it would benefit me enough to consider only amps with integrated DSP technology?
I will be using this primarily for a bass rig. I will require crossover feature, which is available on some analog, non-DSP amps.

Advice? Thanks in advance.

[bongomania]

DSP means "digital signal processing", and it just means your signal will be converted to data, have EQ, limiting, and possibly other processing done on it, and then be converted back to analog. It's like having a digital multi-fx pedal dedicated to EQ, compression, crossover, and that sort of thing.

You don't "need" it, and some people won't even want it; but if you do want a "full set" of EQ, compression, crossover, and other processing built into the power amp, then you are looking at DSP for sure.

If you don't care about anything but the crossover, then you don't need DSP. Also, all of these features can be found together in the form of a 1-rack-space preamp, if you wanted to stay in the analog domain.

[Calaverasgrande]

I've dealt with DSP amps before. If you dont grasp setting up a PA system with an EQ, crossover, and dynamics control in the drive rack, than I would not go out of my way to get a DSP amp. It has the potential to give you serious headaches. I'm actually saying this not as a bass player or former sound guy, but as an IT guy that supports users. Quite often my users end up with software/hardware that surpasses their needs. If they dont have the time to learn the features than it's just wasted money. Better off getting a good simple amp and save the processing for the preamp.

[T-Bird]

Hi.

DSP is only a short for Digital Signal Processing, by itself it doesn't tell a thing.

Manufacturers will (and do) use the term DSP to sell more units to uninformed customers.

Whether You need DSP in your amp or not, depends mainly on what are the features that you require. For example, cross-over that You mentioned, can be much more versatile if the manufacturer has chosen to design it that way, but not necessarily.

Regards
Sam

[MVE]

I understand that DSP is largely required in Class D amps (peavey IPR, Bergantino IP, etc...) because Class D amps have a horribly unmusical clip and DSP is the only way to get an absolute hard knee limiter to prevent the amp from ever clipping.

Can anyone confirm or refute this or discuss it further? Do all of the new micro bass amps have A/D/A converters in the signal path?

Purists would argue that an analog path is always better, but I have not yet A/B a Peavey IPR against a similar non-D amp.

[chucko58]

DSP is not required in any power amp. It is just a means to an end. Depending on what the DSP implements, it may be worth having, or not.

Some kind of high-pass filter and a clip limiter are good ideas, but also not strictly necessary.

[MVE]

Are there any Class D amps that do NOT have integrated A/D/A converters?

[SeayBass]

this is very helpful. Thank you. After looking at some manuals of units in my price/power range, I have found that the most extensive feature set is crossover & EQ & limiter settings. So far I am not compelled to search exclusively for the DSP amps.

I am grateful and glad to have your input. thanks

[fdeck]

Originally Posted by MVE

I understand that DSP is largely required in Class D amps (peavey IPR, Bergantino IP, etc...) because Class D amps have a horribly unmusical clip and DSP is the only way to get an absolute hard knee limiter to prevent the amp from ever clipping.

Can anyone confirm or refute this or discuss it further? Do all of the new micro bass amps have A/D/A converters in the signal path?

Purists would argue that an analog path is always better, but I have not yet A/B a Peavey IPR against a similar non-D amp.

I don't think this is true. Clipping behavior is something that amp designers have taken seriously for a long time -- especially for amps that are destined for portable or musical use where occasional clipping is likely. I have measured the clipping waveforms on the Class-D amps that I have owned, and they actually seem to exhibit a "soft" clipping behavior. In fact, I punished my EA Micro300 head while watching the output on a scope, and wasn't able to make it do anything untoward.

The micro bass amps don't have an A/D/A arrangement. They are essentially analog from the input jack to the Speakon. Some may have a microprocessor "supervisory" circuit that looks for conditions such as over-temperature or DC offset, and that manages functions such as channel switching. I suspect that even the ones with true digital preamps (Yamaha, TC Electronics?) still have an analog Class-D power amp -- solely based on what I think probably makes sense from the standpoint of cost and design complexity.

The real amp experts may have more info. I'm more of a spectator than a player in modern power amp design. It's just that I have a neurotic compulsion to understand how things work.

I measured one Class-D amp that exhibited nasty crossover distortion when driven to clipping, but that distortion didn't go away when the signal was dropped back to a normal level, and the amp went back to the dealer an hour later. But that amp isn't on the market any more.

It's interesting that on the DIYaudio forum, folks building their own Class-D amps will usually show a scope trace of a clipping waveform, because clipping response is known to be a merit of a well designed amp.

[Passinwind]

Originally Posted by MVE

Are there any Class D amps that do NOT have integrated A/D/A converters?

Yes, many (probably most), going back to the Crown K series and beyond. The new amps Peavey have actually been selling do not either, so far.

They sound just fine that way, in my experience. I have the same plate amp the Berg IP uses, and bypassing the DSP functions as much as possible still sounds fine. The DSP based limiting function is great for protecting speakers, but the separate limiting scheme in the power amp proper still sounds OK. OTOH, I nearly always prefer staying off the limiter with any amp of any topology.

[bongomania]

Originally Posted by MVE

Are there any Class D amps that do NOT have integrated A/D/A converters?

You've fallen victim to the marketing term "digital amp". So-called digital amps are almost never digital, they just use a switch-mode power section that can be described as having a "binary" or "digital-like" quality in the way it handles current. In other words, your audio signal stays completely analog in almost all cases. There are a few Class D amps that do use A/D/A, namely the ones that have DSP processing. But again, most Class D amps do not have DSP.

[MVE]

Thanks for help and info everyone.

[fdeck]

Originally Posted by bongomania

You've fallen victim to the marketing term "digital amp". So-called digital amps are almost never digital, they just use a switch-mode power section that can be described as having a "binary" or "digital-like" quality in the way it handles current. In other words, your audio signal stays completely analog in almost all cases. There are a few Class D amps that do use A/D/A, namely the ones that have DSP processing. But again, most Class D amps do not have DSP.

I suspect that even the Class-D amps with DSP still have a basically analog power amp circuit. They may monitor output voltage and current, and apply corrections to the signal being fed to the power amp.

I remember when CD players came out, and high-end speakers were labeled as "digital ready."

[BassmanPaul]

Originally Posted by MVE

Are there any Class D amps that do NOT have integrated A/D/A converters?

I'd say most of them.

[seamonkey]

Peavey IPR with DSP have to be the best deal in DSP
They have built in "Waves" plugins like Maxxbass that you'd pay big bucks for yourself.

It's not going to be as versatile as a Waves MaxxBCL - but it's going to be a heck of a lot cheaper!

[Calaverasgrande]

Originally Posted by fdeck

I suspect that even the Class-D amps with DSP still have a basically analog power amp circuit. They may monitor output voltage and current, and apply corrections to the signal being fed to the power amp.

I remember when CD players came out, and high-end speakers were labeled as "digital ready."

add to that Sony's good hadphones! the 7506 V6 etc.
About SMPS class D. From what I gather it basically "samples" the AC and turns it into DC.

[Passinwind]

Originally Posted by Calaverasgrande

About SMPS class D. From what I gather it basically "samples" the AC and turns it into DC.

There are plenty of Class D amps that don't use an SMPS, and plenty of SMPS equipped amps that are not Class D. So the terms are not joined at the hip, allsimsayin'.

[will33]

I see nothing.

Sorry but that's funny./=

[Passinwind]

Originally Posted by will33

I see nothing.

Sorry but that's funny./=

"Give me back my gun, or I'll SHOOT!"