Digital amp kits

[willawake]

theres a lot of noise on various forums about these digital amp parts http://www.hypex.nl/

looks really interesting
http://www.gweep.net/~rocko/UcD400/
and not that difficult
http://www.tnt-audio.com/ampli/udc180_e.html
http://home.wanadoo.nl/dezaire/UcD180AD/UcD180AD.htm

[Logistics]

Re: Digital amp kits

You mean Class D amplifiers? They became a popular item because of their simplicity and ability to create lots of power for cheap, but they also make more distortion so they are commonly used for subwoofer amplifiers where that is not such a big deal. (to some people, anyway) If you're looking for something HiFi, you don't want Class D.

[zandrax]

Re: Digital amp kits

You mean Class D amplifiers? They became a popular item because of their simplicity and ability to create lots of power for cheap, but they also make more distortion so they are commonly used for subwoofer amplifiers where that is not such a big deal. (to some people, anyway) If you're looking for something HiFi, you don't want Class D.

There are some class D hi-fi amplifiers: mine is the old Sonic impact T-Amp employing a Tripath chip, but they're manifactured from Nuforce, Pioneer, Marantz and others (there is even B&O, but I would consider it a "life style equipment" producer more than a hi-fi manifacturer). Most chips are cheap, are reliable, deliver a lot of power and are employed in "professional" gear (discos, live concertos and such) but they're like diesel engines: adopted by trucks and even by cars (at least in Europe).
Anyway I'm not mad at you, only a bit curious:
1) which class D amp did you listen in order to detect such a distortion?
2) tubes amps are known for their analog sound: isn't analog sound a distortion of odd-order harmonics?

Zandrax

[zandrax]

Re: Digital amp kits

isn't analog sound a distortion of odd-order harmonics?

Sorry, I wanted to write even-order harmonics, which are more pleasant for the ear than odd-order ones.

Zandrax

[i4004]

Re: Digital amp kits

logistics i think you didn't read all links willa provided...

zandrax: one of willa's links is comparing this to tube amp sound.

[zandrax]

Re: Digital amp kits

zandrax: one of willa's links is comparing this to tube amp sound.

I know and you got my points: the UcD goal is to sound analog, tube-like, which means coloring the sound with even-order harmonics.
Since Logistic is pointing out distortion as a weakness for class D amps (I think he's referring to odd-order harmonics distortion, which is unpleasant to listen to: sound become quite harsh) and suggested looking for other amps, I wanted to know which amp did Logistic listen to and to discuss my thoughts:
- if distortion is something to be minimized in an hi-fi amp, then tube amps aren't strictly speaking hi-fi gears because of even-order harmonics distortion;
- if tube amps are hi-fi, then the UcD is hi-fi too because it sounds like a tube amp; furthermore, this means that class D equipments sound so different from each other you can't draw general conclusions, only per-case ones.
At least these are my 2 cents.

Zandrax

[Logistics]

Re: Digital amp kits

I'm not comparing tubes to solid-state, I'm comparing Class D design to typical Class AB and A. You can make an exotic sounding Class D amplifier, but Class D is not accepted by most as HiFi; probably because of the more complex design and the required integrated circuitry involved. In my experience, when dealing with Solid State, HiFi usually comes in the form of a large (due to necessity) amplifier using a linear PSU (non-regulated) with huge heat-sinking and, typically, toroidal transformers.

In any case, there are high-end examples of each. Take sound-cards for example! Usually, they are class AB at best, and they rely on the PC's PSU which is all Pulse Modulation. Many people consider that to be HiFi. I suppose the term is relative.

[willawake]

Re: Digital amp kits

You mean Class D amplifiers? They became a popular item because of their simplicity

Class D is not accepted by most as HiFi; probably because of the more complex design and the required integrated circuitry involved.

[gonzo0815]

Re: Digital amp kits

Well, HIFI was an standard set by the German DIN 45500. It specified a bandwidth of 20 Hz to 12,5 kHz at nominal RMS power with not more then 1% THD.

Today HIFI does mean nothing, as the new standard defined in the EN 61305 does not bother with minimal requirements.
So i think most class D amps will certainly comply with the older HIFI requirements, but i think we all know, that those are noting compared with what even a cheap solid state amp could archive.
Any sure, most sound cards can archive those minimal specs easily too.

[arneson]

Re: Digital amp kits

Gonzo 0815,
I don't meen anything by this except to correct the word you used.
To archive means to store away safely, I think you meant to say achieve.
Which means to meat a goal or specification.
FYI.

[i4004]

Re: Digital amp kits

so logistics, what's wrong with this amp's sound?

[zandrax]

Re: Digital amp kits

@ Logistic: I acknowledge I missed your point comparing tube to class D amps instead of solid state to class D ones, but you could have stated your thoughts explicitly: I didn't know the classes you were comparing to.
Anyway I don't want to be the devil's advocate: if you have any good reason to warn Willa about the UcD kit, then write it. Previous claims of distortion and design issues (too simple or too complex one?) without any supporting proof aren't good reasons, that's all.
In i4004's words, what's wrong with it?

Zandrax

[Krankshaft]

Re: Digital amp kits

Here is yet another single channel Class D amp.

This one is a kit constructed of SMT parts.

http://www.ramseyelectronics.com/cgi...ction&key=UAM2

[Logistics]

Re: Digital amp kits

I'm sorry, in the popular form I was speaking about, it was easier to achieve good results in a subwoofer amplifier because you didn't have to worry about the distortion as much. Implementation was simpler, unless you wanted to make the amplifier sound more exotic; which is the case with great sounding T-amps. Technically, as you'll read on Wiki, they are not digital, but then, what amplifier is digital? Speakers don't run off digital.

They are cheaper and simpler to implement, unless you want really good sound; then Class A is much simpler, but MUCH more expensive if you want to reach the same power levels.

There is no way I could know what that amplifier sounds like without actually listening to it. If it's not expensive, give it a whirl. Just don't expect to power anything big with it. You can just look at it and tell that there's no significant amperage running through it.

[Krankshaft]

Re: Digital amp kits

I honestly can say in this digital age no matter how fancy your setup is it all comes down to old fashioned analog speakers.

It makes me think that we will eventually hit into a brick wall when we've maxed out what our ears can percieve.

What's next do we need digital ear upgrades to get better sound ?

[zandrax]

Re: Digital amp kits

I'm sorry, in the popular form I was speaking about, it was easier to achieve good results in a subwoofer amplifier because you didn't have to worry about the distortion as much. Implementation was simpler, unless you wanted to make the amplifier sound more exotic; which is the case with great sounding T-amps. Technically, as you'll read on Wiki, they are not digital, but then, what amplifier is digital? Speakers don't run off digital.

Right: class D doesn't mean Digital though most amp are wrongly dubbed this way. There are a few manifacturers claiming their amp are fully digital (e.g. Tact audio, Lyngdorf Millennium) but I never got into details.

There is no way I could know what that amplifier sounds like without actually listening to it.

True: only Chuck Norris can judge a book by its cover

If it's not expensive, give it a whirl. Just don't expect to power anything big with it. You can just look at it and tell that there's no significant amperage running through it.

I wish I was as confident as you.
The smallest is 180W at 4 Ohm (say around 90 at 8 ohm), I think the speakers it'd have hard time in driving are low efficiency ones such as some electrostatic speakers. There are 400 and 700W modules if you need beefier amplifiers.

What's next do we need digital ear upgrades to get better sound ?

Nope: mine are still on warranty so I won't touch them

Zandrax