Hypex Class-D

[michaD]

Salut everybody,

I am playing a SansAmp TRI-A.C. through an elder QSC-PA amplifier (USA 360, bridged).
To get rid of the very heavy (but very powerful and reliable) QSC I would like to use one of these modules

http://www.hypex.nl/product/ucd-amplifier-modules/ucd400hg.html

together with the recommended switchmode power supply.
Does anybody ever used an UCD400 or UCD180 as a guitar power stage?

Are there any commercial guitar-amps in class-d? Like Crate's PowerBlock with the TDA8920B? On the datasheet of the successor TDA8950 no pro-audio applicatons are recommended. Do they have reliability issues?

Greetings,

Michael

[J M Fahey]

The bass guys are using tons of 500W class amps, where complexity and price are compensated by weight and heat loss.

Now on guitars where 100W is usually way too much they are not that attractive.

But of course they must be usable.

By the way, don't much understand the use of a Bridged QSC360  :loco for guitar.  :cheesy:

[teemuk]

Are there any commercial guitar-amps in class-d?

Yes.

They have seemed to gain a lot of popularity within last five years. Powerblock for a while was almost only "compact" class-D guitar amp out there but now plenty of products have flooded the market: Bad Cat Unleash is class-D, Quilter amps are class-D, some DV Mark amps are class-D, Matrix just released a Marshall clone with tube preamp and class-D power amp.... Plenty of them now. Of course they've been a mainstay in bass amps for almost a decade by now. Guitar scene is always at least a few years behind of everything, if not few decades. ;-)

That said, few years ago it would have been customary to loathe the idea of a class-D power in a guitar amp, and (gulp) a switchmode supply. Now everyone seems to be raving how great they are.

It's funny how things change.

Do they have reliability issues?

Everything does, especially when not implemented right. I think many of these modules still have a lot to work on generating their rated output power continuously. The TDA8950 is probably aimed for "domestic" duties because it couldn't achieve that rated output power reliably when operating at different crest factors associated with pro audio. ...Not to say that similar issues wouldn't apply to even generic linear integrated chips like TDA7294, LM3886, TDA2050, etc.

[michaD]

I bridged the QSC (I meant USA370) just to keep both channels (110W @ 8Ohms each) busy and evenly loaded. Not that I ever would need the power.

And it's great fun to startle the horn section from time to time ...

[michaD]

Hi Teemu,

thanks a lot for mentioning QuilterLabs. I didn't know those amplifiers yet. Funny enough, one won't find the term "class-d" anywhere in their product descriptions. As if that must be kept a secret.

The Quilter Tone Block is exactly what I had in mind. So if I was reasonable (I am not), I should give up the Hypex-plan ...

Guitar scene is always at least a few years behind of everything, if not few decades. ;-)

Maybe a PWM-amp with RF-Power-Tubes would be the way to go?

Regards,

michael

[greenm01]

That said, few years ago it would have been customary to loathe the idea of a class-D power in a guitar amp, and (gulp) a switchmode supply. Now everyone seems to be raving how great they are.

Until an unobtainium proprietary component/chip fails in the PSU or Class-D board, and you have to throw the entire amp into the trash bin. If the warranty is expired, one will be out of luck.

Go with a linear power supply and toroidal power transformer; easy to maintain and the transformer will last forever.

[Roly]

Unless you do a lot of gigs in aircraft ( ), weight is generally of less concern than MTTR - Mean Time To Repair - for the working musician (and a switch mode amp isn't going to make the speaker cabs any lighter either).

Class-D audio has been around since the 1960's and largely ignored by everybody except people doing mega PA, and both with their own good reasons.

Speaking as someone who used to service thyristor Variable Speed drives up to 100HP running on 3 phase 415VAC, I wouldn't be keen to take on a faulty Class-D amp.

"The pioneers catch the arrows."

"Dipped over the bleeding edge."