computer audiophile on the cheap Class D amplifiers, can a chip sound as good as a regular amplifier?

[Ajax]

On 15/04/2017 at 8:38 PM, Jud said:

 

Only "side" I might join is the one with the good music.

 

Couple decades ago in Canada, law firm ski trip:

 

Lisa: Why are we getting on the smoking bus?  You don't smoke.

 

Me: They have a better party.

 

Very funny Jud - and also very true.

 

[GUTB]

Well....the manufacturer said the only difference between the nc1200 and nc500 was power output yet the nc1200 is ridiculously expensive and people report it is much better?

 

On the lower end of the nc1200 scale I can afford it. But...if Iceedge is coming out will it just be a sucker move to get ANY class D as of now?

[Ajax]

9 hours ago, rikard said:

As an actual owner of a Hypex NCore NC500 based Nord One dual mono amplifier I can chime in that it's probably one of the most cost efficient things I've ever bought. I was looking at upgrading to a quite expensive integrated amp costing many times more, but then I was hooked by the 100+ pages Nord thread in another forum (starting with audio and ends with a sharp toothed fish), I read it with excitement from start to finish and just couldn't resist doing an "experiment".

 

 

+1

I also read that thread and purchased the Nord One Up NC500 in Stereo format with Sonic Imagery 994 op amp (about US$2k including shipping) and have been very happy with it driving my ATC SCM19 speakers. FYI Colin believes there is no difference in sound quality between the stereo and mono versions and it saves you around US$120 with one less box.

 

Like bigbob (and most at CA) I enjoy experimenting with what's available for the least amount of money and although the Nord is outside his budget IMO it delivers a very neutral sound with great transparency and amazing specs and power for the price.

 

As a total contradiction I have also just purchased a 20 year old re-capped Parasound HCA-1206 power amplifier (US$700 secondhand), which is a 6 channel bridgeable John Curl design. Weighing a massive 71ibs (32kg) I'm having trouble working out how to get it from Perth to Sydney, a distance of 2500miles (4000kms). I plan to incorporate it into a home theatre system with an Emotive UMC200 as the processor (US$300 also second hand). Not sure what I was thinking buying this beast instead of a new multichannel lightweight D class amp, which would have been much more practical, but I saw it on eBay and read up on Mr Curl and decided it would be fun to have a classic "vintage" amp.

 

[jabbr]

7 minutes ago, Ajax said:

 

+1

I also read that thread and purchased the Nord One Up NC500 in Stereo format with Sonic Imagery 994 op amp (about US$2k including shipping) and have been very happy with it driving my ATC SCM19 speakers. FYI Colin believes there is no difference in sound quality between the stereo and mono versions and it saves you around US$120 with one less box.

 

Like bigbob (and most at CA) I enjoy experimenting with what's available for the least amount of money and although the Nord is outside his budget IMO it delivers a very neutral sound with great transparency and amazing specs and power for the price.

 

As a total contradiction I have also just purchased a 20 year old re-capped Parasound HCA-1206 power amplifier (US$700 secondhand), which is a 6 channel bridgeable John Curl design. Weighing a massive 71ibs (32kg) I'm having trouble working out how to get it from Perth to Sydney, a distance of 2500miles (4000kms). I plan to incorporate it into a home theatre system with an Emotive UMC200 as the processor (US$300 also second hand). Not sure what I was thinking buying this beast instead of a new multichannel lightweight D class amp, which would have been much more practical, but I saw it on eBay and read up on Mr Curl and decided it would be fun to have a classic "vintage" amp.

 

Nice.

 

The power transformer is likely a big component of the weight.  Class D really really really needs clean power because that awesome power efficiency means that the power supply is essentially hooked up directly to the speakers so I trust that in that $2k you got at least $100 of power transformer  

[VoicesInMyHead]

9 minutes ago, jabbr said:

Nice.

 

The power transformer is likely a big component of the weight.  Class D really really really needs clean power because that awesome power efficiency means that the power supply is essentially hooked up directly to the speakers so I trust that in that $2k you got at least $100 of power transformer  

 

The Nord One amp contains two Hypex SMPS1200A700 PSU’s according to specs.... it's a true dual mono configuration with double of everything, even in the one-box stereo version.

 

I definitely can attest that it benefits from good power though, I have an Ansuz Diamond power cable to my Nord, costing several times more than the amp itself, which might not make sense, and especially not in this thread, but it sure did make an improvement over a less powerful cable I tried first (same brand, lower level).

[GUTB]

I read about the Theta Digital Prometheus which uses the NC1200 where they said giving them a gigantic 1.4kv linear power supply was the best option....only 110lbs for the pair lol. But then they a discontinued it for some reason. Does class D really want to have a linear power supply?

[bigbob]

9 minutes ago, rikard said:

I definitely can attest that it benefits from good power though, I have an Ansuz Diamond power cable to my Nord, costing several times more than the amp itself, which might not make sense, and especially not in this thread, but it sure did make an improvement over a less powerful cable I tried first (same brand, lower level).

 

[bigbob]

It always ends up back to the power. The recent introduction of power conditioning as an essential part of any system was brought home to me when I was given a Chang Lightspeed Encounter. I live in a post WWII apartment, built before anyone thought it a good idea to ground the outlets. Two circuits, with everything from two air conditioners, a refrigerator, and common household appliances plus the stereo--so much for a dedicated circuit from the power meter... The combination of the HFC MC-0.5 and the Chang means my stereo system is being properly fed with clean, conditioned and magnetically affected power.

Would I have ever spent $999  on a Chang Lightspeed as part of a "CAOTC" system? ... probably never, but it sure made a difference in the sound floor. And part of being cheap, means having friends who give nice gifts.

[Jud]

58 minutes ago, Ajax said:

Not sure what I was thinking

 

59 minutes ago, Ajax said:

decided it would be fun

 

Answered your own question there, didn't you?

[unbalanced output]

On the signals. When you convert a digital into an analog signal (assume the conversion is perfect), you'll be left with a serrated modulation since the conversion has a certain resolution. If you want to measure this signal, you'll need a much higher resolution (rule of thumb is one order of magnitude greater). With a standard oscilloscope (say 16 bits / 100 kHz), one will not be able to see the quantization errors (eg. jitter) created by the amp which has a carrier frequency of the same order. This way, a cheapo amp will measure good and a good quality amp will measure... just equally good. You'll need some better measurement tools in order to get meaningful information. 

 

I think the same idea applies to PWM in class D, PCM and DSD. However, the output stage has quite an impact in minimising these quantisation errors in a DAC. Also note that the DSD frequencies and resolutions are much higher which also minimises these problems. However, a simple class D amp will not have an additional stage at the output, therefore afecting the sound. I'm sure that the good amps mentioned here take good care of this in their design!

[unbalanced output]

8 hours ago, rikard said:

 

Golden Atlantic, tube rectifier, balanced, volume control. It's difficult to describe how it sounds in words, but as I already said I'm very happy with the combination and don't really miss anything. I honestly think any Lampi model would be a good match.

 

Next week I'll hopefully get a passive preamp from Music First to try and see if it makes any difference. Not that I feel that I need it, but I'm curious to try it...

 

Thanks. I don't bother about the tube rectifiers, balanced circuitry and so forth. However, I like the idea of a clean path on the DA output. Can't wait to have one in my hands to see how it sounds!

[Abtr]

On ‎19‎-‎4‎-‎2017 at 8:47 PM, bigbob said:

It always ends up back to the power. The recent introduction of power conditioning as an essential part of any system was brought home to me when I was given a Chang Lightspeed Encounter. I live in a post WWII apartment, built before anyone thought it a good idea to ground the outlets. Two circuits, with everything from two air conditioners, a refrigerator, and common household appliances plus the stereo--so much for a dedicated circuit from the power meter... The combination of the HFC MC-0.5 and the Chang means my stereo system is being properly fed with clean, conditioned and magnetically affected power.

Would I have ever spent $999  on a Chang Lightspeed as part of a "CAOTC" system? ... probably never, but it sure made a difference in the sound floor. And part of being cheap, means having friends who give nice gifts.

Hi Bigbob, I have an off-topic question. Is it correct that you use the Chang Lightspeed power conditioner to feed your audio gear from an ungrounded power outlet?

[bigbob]

3 hours ago, Abtr said:

Hi Bigbob, I have an off-topic question. Is it correct that you use the Chang Lightspeed power conditioner to feed your audio gear from an ungrounded power outlet?

I don't know if it is 'correct', but this circa 1948 apartment is grandfathered with respect to the electrical code. As long as there are no three prong outlets, it is within code. I wouldn't want to take the Chang out of my power supply line, and my landlord doesn't want to rewire the five units....

[mfsoa]

I know that the latest Digital Amplifier Company Maraschino Class D amps are excellent. 

-Mike

[jmjohnson]

On 4/18/2017 at 1:11 PM, Ralf11 said:

the following have been well reviewed:

D-Sonic

nad M

Rogue Audio Sphinx

Merrill Audio Taranis, Veritas

Rowland M925

Nuforce

Technics SE-R1

EPC

Yamaha's EEEngine

SDS

Peachtree Nova

Hypex

Acoustic Imagery Atsah 

Bel Canto

Nord

Nu-prime

Mola Mola Kaluga

PS Audio

Primare

Spectron

ASP

 

 

 

 

 

I have had the Merrill Audio Veritas Monoblocks for a number of years, they are based on the Hypex NC1200. I am really happy with them, and Merrill is a really nice guy to deal with

[R1200CL]

On 19.4.2017 at 8:31 PM, GUTB said:

I read about the Theta Digital Prometheus which uses the NC1200 where they said giving them a gigantic 1.4kv linear power supply was the best option....only 110lbs for the pair lol. But then they a discontinued it for some reason. Does class D really want to have a linear power supply?

 

I don't think discontinued. Where did you get that information?

http://thetadigital.com/prometheus_amplifier_info.shtml

 

Alao ATI that owns Theta has great class D Hypex amps available. 

http://www.ati-amp.com/AT52XNC.php

[Jud]

It does seem a little paradoxical to have a huge honking linear power supply for a switch mode amp why?  Because everyone knows linear is better than switching??

[GUTB]

Well, I'm about to head over to AXPONA for a full day of listening. I'll be sure to check out some of these products.

[elcorso]

52 minutes ago, Jud said:

It does seem a little paradoxical to have a huge honking linear power supply for a switch mode amp why?  Because everyone knows linear is better than switching??

 

Sometimes it's hard to get "switching noise" out of your whole system when you have a Class D power amp., like in some self powered Subs (my case).

 

I don't have "switching noise" when the main speakers are feed by my Class D power amps. Maybe they have LPSU?

 

Roch

[GUTB]

The mbi system is STUNNING. Complete disappearing act from speakers. Might as well be sitting In front of the performance. Kind of like being in a movie theatre.

 

Stopped into the Merril Audio room but it was totally packed will come back later.

[Ralf11]

What is the mbi system?  Google is showing me breast cancer tmts...

[jabbr]

3 hours ago, Jud said:

It does seem a little paradoxical to have a huge honking linear power supply for a switch mode amp why?  Because everyone knows linear is better than switching??

 

With a Class D amp, the speakers directly see the PSU, so if PSUs are important, they are important here. You may not need absolute voltage accuracy and to save on the big caps, a cap multiplier may fit the bill.

[esldude]

2 hours ago, Ralf11 said:

What is the mbi system?  Google is showing me breast cancer tmts...

My guess is he meant MBL.  

[Jud]

28 minutes ago, esldude said:

My guess is he meant MBL.  

 

They do like to put on impressive demos at shows.  And the speakers look different enough to be very interesting.

[semente]

On 15/04/2017 at 5:57 AM, GUTB said:

For those of you who believe class D is competitive, how do you get a high quality 3D soundstage and musical timbre with class D?

 

For me, timbre is a property of the recording (the sound of vocals and instruments in a room) and can be best heard with "transparent" gear.

3D soundstage depends on the room acoustics and on speaker positioning (assuming that the speakers have a nicely balanced power response). 

 

R