UCD180 questions

[jam]

Jan-Peter,

...back to the subject. Could you tell us more about the high powered units that will be coming out. Will they be bridged units and will they be stable into two ohms? I have really inefficient speakers.

Regards,
Jam

[Jan-Peter]

Jam,

I hope the moderators don't see this answer as any form of an advertisement. But the answer is as follows;

The UcD400 is put in production, we have to wait for around 4 weeks til we receive the first batch.

The level for the shortcircuit protection is not yet fixed, will be test next 2/3 weeks. Mine target will be 15A rms, so this will be a +/-450W in 2 Ohm.

In a way it is not a problem at all to connect a 2 Ohm loudspeaker on the UcD400, when you ask to much current the amps goes in protection.

Cheers,

Jan-Peter

www.hypex.nl

[peranders]

Jan-Peter, my personal view is that answering techincal questions is not advertizing but if the answers is positive it's sort of advertizing but hardly over the limit and as you mentioned, you didn't start this thread.

.... I'm also very tempted to try one of your modules, can't deside though if it's going to be UCD180 or UCD400...you can't offer a promotional price for the first 100 modules or so?

[jam]

Jan-Peter,

I am sorry I was not too clear with my question. I ment what comes after the UCD400? What higher power units are on the drawing board?

Regards,
Jam

[Jan-Peter]

Jam,

At the "drawing board", I have a 700W at 4 Ohm and 1kW at 2 Ohm (1.2kW?) version available....

Did not yet started with a prototype. We are going to move to a new building at the end of this months. Quite busy at the moment.

When we are all settled and everything is running up again, this will be my next project.


Will these be sufficient for your "hungry" speakers


Regards,

Jan-Peter

www.hypex.nl

[mhelin]

Could you briefly tell how UcD180 compares to Tripath evaluation modules and what are the main differences? I'm considering UcD's for active monitors (though may first build GC amps as they are almost free, unfortunately the transformers are not compatible with class-D/T amps).

OT: About the forums, I see Lumenlab (brainchild's diy projector business) everywhere, still you ask for donations, what's this all about?

[mhelin]

Another qustion: As the UcD bandwith is limited to 20 kHz, so is the DAC filter needed at all, could I just use the DAC's differential output directly to UcD (or will I start hearing some strange noises)?

Edit: The volume control will be problem though.

[UrSv]

Originally posted by mhelin
Another qustion: As the UcD bandwith is limited to 20 kHz, so is the DAC filter needed at all, could I just use the DAC's differential output directly to UcD (or will I start hearing some strange noises)?

Edit: The volume control will be problem though.

Is it limited to 20 kHz? Why would that be?

[peranders]

Originally posted by mhelin
OT: About the forums, I see Lumenlab (brainchild's diy projector business) everywhere, still you ask for donations, what's this all about?

The donations are for diyaudio.com Lumenlab has a paid add.

Raising money to diyaudio.com goes pretty well but some more is needed if I'm not mistaken.

Push the button below and donate 20, 50 or 100 dollars or whatever you can afford. If Paypal isn't OK for some reason just talk to Audiofreak or some of the moderators.

[rha61]

Hi

after a lot of experimentations ( and some incidents )
i think that the UCD stage is VERY transparent and neutral so you can easily sculpt its sound , depending on your taste :

For filtering the power supply I tried standard Philips caps (10000/63) and Elna Audio (12000/71 ) , the result was completly different , the sound was smooth , untight bass and deep stage with the Philips and a lot faster presentation with the Elna , less deep stage because of the very tight bass , incisive midrange and treble because of speed

It's the same story about the input buffer :
the 5532 with standard or BG-N interstage caps has a smooth sound , fluid and airy , it's an "easy listening" even with bad records
The OPA2134 with no interstage caps is faster , nice sound too , between the 5532 and AD8620
The AD8620 with no interstage caps is very transparent , very fast , needs a few days for burnin , the consequence is that it has an amazing presentation with good records but doesnt forgive with bad ones . If you add BGN caps with the 8620 , you hear it , transparent and neutral capacitors dont exist and i think that having one with the tweeter is enough
With a 15mv offset source , there is no problem with the 8620 with no caps , at 100mv there is power supply pumping effect (i've seen my +50v going to +60v ) .

In all these experimentations , the UCD was always sounding nice (with right response on transcient sounds compared to other classD amps) , it is remarkable that there was never harshness...
I'm very pleased with the 8620 but i think the best way for the buffer stage is a discrete one with not much components , maybe powered by battery , this will be the next step

Alain