Hypex versus ColdAmp

[fdeck]

Sorry if this is a FAQ. I would like to get opinions on the choice between Hypex and ColdAmp modules (or any other brand that I should consider). No holds barred. Anything that I should know from a technical, musical, practical, or other standpoint.

I decided that for various reasons, I am not ready to try rolling my own Class-D module. My application is to build a powered speaker for musical instrument use. Right now I play string bass and some electric bass, and a roughly 150 Watt amp is more than enough for the work that I do. But I am trying to lighten the load by replacing a lead sled with a nice slick Class-D module.

[BWRX]

Why don't you get one of each and tell use what you think?

[tinitus]

A new one from 41hz, looks nice and solid

http://www.41hz.com/

[raintalk]

Coldamp has an SMPS. ColdAmp is also creating a 800w module to be released soon.

NewClassd.com is another option. Take a look at their Quality procedures at their site. Amazing torture tests before shipping a module.

Hypex claimed to be creating an SMPS at one time. I don't know where this went.

Coldamp will make you an SMPS for any module.

Seeing as the power supply is a key link to the quality and reliability of module, I'd just stick with coldamp. I hope to buy some coldamp modules soon.

[ackcheng]

I have tried coldamp PSU - rock solid. But I have not tried Coldamp class D module

[doublestop]

I also play upright and electric bass. I recently assembled a simple mono UCD400 prototype with a 500VA toroidal xformer, Hypex softstart and 15K uf of capacitance per rail. I've used it with the upright (Realist and Underwood) on jazz gigs around Seattle through both an 8 ohm Acme B1 and a 4 ohm Acme B2 (separately, not together!). I felt it sounded more solid than the Acoustic Image Clarus, which I found easy to overload with the Realist. Next step is to spring for the Coldamp SMPS and make a really lightweight rig. Then, on to the UCD700! Reliability has been my priority throughout.

fdeck - I used the UCD400 with a modified version of your BBBB (single channel, delete Baxandall, add HP filter and 2 band para eq). Thanks for making the circuit and construction details available to all.

[Pierre]

Hello all.

I am also a happy user of Coldamp modules (first, BP4078 with LPS30 linear supply, and recently I moved to their SPS80 switching supply).
Sound is transparent, with tight and deep bass. Noise floor is extremely low. The modules are rudged, full of features and very convenient to install, with very nice documentation and application notes. For me, excellent value for the money as compared to others.

I must say that Coldamp stuff are also extremely helpful and nice to treat. They can even provide custom-voltage versions of their switching power supplies, even with single-output, making them useful for our old "Gainclones", other Class-D products, etc.

BTW, I eventually found this...

http://www.oslo-audio-society.com/coldamp.html

Unfortunately, it is in Norwegian. May anyone translate it, please (not with an automatic translator, please, I already tried with awful results :-) ?

[fdeck]

Originally posted by doublestop
I also play upright and electric bass. I recently assembled a simple mono UCD400 prototype with a 500VA toroidal xformer, Hypex softstart and 15K uf of capacitance per rail. I've used it with the upright (Realist and Underwood) on jazz gigs around Seattle through both an 8 ohm Acme B1 and a 4 ohm Acme B2 (separately, not together!). I felt it sounded more solid than the Acoustic Image Clarus, which I found easy to overload with the Realist. Next step is to spring for the Coldamp SMPS and make a really lightweight rig. Then, on to the UCD700! Reliability has been my priority throughout.

fdeck - I used the UCD400 with a modified version of your BBBB (single channel, delete Baxandall, add HP filter and 2 band para eq). Thanks for making the circuit and construction details available to all.

Thanks for the kind words! Did you adapt the printed circuit pattern? Choose different op amps, or other mods?

[doublestop]

I assembled it on perfboard using lowly TL072s (no offense!) I had lying around. Power comes from an 18V wallwart LM317-regulated to 15V. Overkill, yes, but I have an irrational fear of battery-powered gear. And, I have a box full of scrounged wallwarts begging to be used. I'd love to get your pcb from ExpressPCB and wire it up right. Someday...

Ted Enderle

[sek]

Hi,

BTW, I eventually found this...

http://www.oslo-audio-society.com/coldamp.html

Unfortunately, it is in Norwegian.

Yes, and unfortunately they did it wrong!

While going for the professional-grade PowerCon (Neutrik) mains plug, they preferred the more beautiful one over the correct one...

They placed an output on the unit and used an output jack to deliver mains input!

Whatever the build quality, they likely didn't go for safety and sound quality in this project.

Just my ,
Sebastian.

PS:
The correct PowerCon input plug would be blue, which doesn't seem to match the brushed metal surface.
The way they built it, the unit is still safe from touching mains contacts, but the wire isn't. It can be made touch-proof, but only if you build the mains wire yourself (or buy theirs) and never go through any agency test and certification...