Has anybody direclty compared Class D and Class A A/B amps?

[satbox]

It won't void the Warranty. It's much easier than you think. It's pretty much the same as just simply flipping a switch. Your preamp has more than enough juice. It will probably result in a bigger upgrade than that Mola Mola pre.

Simply move the jumpers to the unbuffered position like in the photos.

View attachment 23811View attachment 23812View attachment 23813


I have the exact same LM4562 buffers here for the NC500's. Comparing going from my pre without them, to with, is night and day. You don't realize how much coloration they add until you hear them without it. And with a pre as powerful as yours, they aren't required at all. They are just there for if you have a pre or DAC with only around 4v output.

If you do this it will be better than the Mola Mola amp. Because there's no buffer better than no buffer if it's not required. Think of it as connecting 2 preamps back to back. No matter how good they are, it won't be better, if 1 preamp has enough drive on it's own.

I plan to use an NC500 dual mono amplifier directly connected to my DAC (T+A DAC 8 DSD). The analogue outputs balanced (XLR)
of the DAC are rated 5,0 Veff. My speakers are 4 ohms. If I disconnect the LM4562 buffers, how it will impact the output volume?

 

[mountainjoe]

I see you’ve already made a decision but fwiw, I have compared the Merrill Veritas and Mola Mola in my system against a pair of VTL MB450MKIII monoblocks (in normal A/B pentode mode).

The Veritas monos sounded thin in my system - lacking any harmonic textures and a slight bit of grain in the highs. I preferred the Mola Mola’s to the Veritas as it was fuller in sound - espcially in the lower mids and had very nice smooth highs with no grain at all./

That said, my VTL’s were richer and conveyed more complex harmonic textures than either class D amps. BTW - I had about 30 folks also at the comparison and the overwhelming consensus was the same as mine - VTL best, Mola Mola second, and Veritas third.

Frankly I wasn’t impressed by the Veritas - unless you prefer thin, dry sounding amps.

Good luck with your new amps!

Cheers, Joe

 

[satbox]

I see you’ve already made a decision but fwiw, I have compared the Merrill Veritas and Mola Mola in my system against a pair of VTL MB450MKIII monoblocks (in normal A/B pentode mode).

The Veritas monos sounded thin in my system - lacking any harmonic textures and a slight bit of grain in the highs. I preferred the Mola Mola’s to the Veritas as it was fuller in sound - espcially in the lower mids and had very nice smooth highs with no grain at all./

That said, my VTL’s were richer and conveyed more complex harmonic textures than either class D amps. BTW - I had about 30 folks also at the comparison and the overwhelming consensus was the same as mine - VTL best, Mola Mola second, and Veritas third.

Frankly I wasn’t impressed by the Veritas - unless you prefer thin, dry sounding amps.

Good luck with your new amps!

Cheers, Joe

Hi Joe, it is your opinion/taste and I respect it. At my side, I don't like warm sound and prefer solid-state amps.

Having said that, I have not taken any decision and I just want an answer to my question...

Cheers

 

[bazelio]

I plan to use an NC500 dual mono amplifier directly connected to my DAC (T+A DAC 8 DSD). The analogue outputs balanced (XLR)
of the DAC are rated 5,0 Veff. My speakers are 4 ohms. If I disconnect the LM4562 buffers, how it will impact the output volume?

The opamps are how they color the sound. That's why you see some Class D amp builders offering discrete op amp input stage choices like Sparkos (warm poo). Other opamps just sound compressed and lifeless. As to volume, you'll have to try and see. The advantage of the op amp input stage is its sky high input impedance. This makes the amp very easy to drive directly from your source. Does the spec sheet for the amp give an input impedance with the op amp bypassed? If it's still reasonably high, and your DAC isn't a wimpy driver, it should then be in the range of 6-8 dB or so. This is based on my memory of a Devialet input stage itself being capable of acting as a 4W amp. (Not that this is an option). Others should be similar, though if their configuration of the op amp is unity gain, i.e. a true buffer, then there would be no difference in volume. So let's say probably at most 6-8 dB.

 

[mountainjoe]

Hi Joe, it is your opinion/taste and I respect it. At my side, I don't like warm sound and prefer solid-state amps.

Having said that, I have not taken any decision and I just want an answer to my question...

Cheers

Hi Satbox - granted the VTLs are on the warm side but the Veritas simply lacked body and weight even based on a neutral reference.

For example, I like to use Jim Morrison’s vocals as a good test as his voice goes deep. It’s a good test of systems in how they reproduce the tonality of his vocals. Those lacking in lower mid and upper bass response will make his vocals sound thin and weak. That’s what I heard from the Veritas.

The Mola Molas were more accurate in this respect and sounded truer to his voice.

I would also agree that the VTLs were adding their own signature to the harmonic textures but in a very musically pleasing way.

So pick your poison - thin sound or warmish sound - I prefer the warm if those are my only two options.

Cheers, Joe

 

[bazelio]

If we're getting subjective, I also like Class D a lot. But not as much as other solid state amps. One consideration with Class D is you need to derate its power spec quite a bit. If you consider the NC500 as a 100W amp only, then you're fine. But distortion rises rapidly at higher power output with these amps. So any subjective comparisons involving Class D are going to be influenced by this depending on what and how hard the amps were driving. Your mileage really may vary, as it's not the so called "attractive distortion" you get from tubes.

Class D can sound great... Musical, natural, etc. It's not for the "big tone" lovers, though. And my main knock has been that it lacks spatial depth compared to other solid state topologies in general. But I do think bang for the buck with the Hypex stuff is excellent. And if the NC1200 (best of the lot IME) were cheaper, I do bet it'd make converts out of even many tube lovers.

 

[mountainjoe]

If we're getting subjective, I also like Class D a lot. But not as much as other solid state amps. One consideration with Class D is you need to derate its power spec quite a bit. If you consider the NC500 as a 100W amp only, then you're fine. But distortion rises rapidly at higher power output with these amps. So any subjective comparisons involving Class D are going to be influenced by this depending on what and how hard the amps were driving. Your mileage really may vary, as it's not the so called "attractive distortion" you get from tubes.

Class D can sound great... Musical, natural, etc. It's not for the "big tone" lovers, though. And my main knock has been that it lacks spatial depth compared to other solid state topologies in general. But I do think bang for the buck with the Hypex stuff is excellent. And if the NC1200 (best of the lot IME) were cheaper, I do bet it'd make converts out of even many tube lovers.

I generally agree with everything you’ve said here and perhaps I wasn’t clear about the Mola Molas - I thought they sounded very nice - just didn’t care for the Veritas.

Also, you reminded me of the spatial depth part as this comparison was quite some time ago - neither of the class D amps approached the depth and width of the soundstage compared to the VTLs, though again, the Mola Molas did better in this respect compared to the Veritas.

 

[satbox]

Hi Satbox - granted the VTLs are on the warm side but the Veritas simply lacked body and weight even based on a neutral reference.

For example, I like to use Jim Morrison’s vocals as a good test as his voice goes deep. It’s a good test of systems in how they reproduce the tonality of his vocals. Those lacking in lower mid and upper bass response will make his vocals sound thin and weak. That’s what I heard from the Veritas.

The Mola Molas were more accurate in this respect and sounded truer to his voice.

I would also agree that the VTLs were adding their own signature to the harmonic textures but in a very musically pleasing way.

So pick your poison - thin sound or warmish sound - I prefer the warm if those are my only two options.

Cheers, Joe

Who said that I'm buying a Veritas, who? They are many Hypex NC500 integrators: Apollon, Nord, Rouge Audio (with an excellent buffer stage OPA1612 based), etc

 

[mountainjoe]

Who said that I'm buying a Veritas, who? They are many Hypex NC500 integrators: Apollon, Nord, Rouge Audio (with an excellent buffer stage OPA1612 based), etc

I never implied you were buying the Veritas - at least not intentionally. I was simply providing more color to my earlier comments on these amps and why I thought they sounded thin.

Sorry but I don’t know enough about your system to answer your question. As Bazelio mentioned, It depends on the input impedance of your amps, their gain, and the output impedance of your DAC. Easiest thing is to try it out and see if you get enough volume for your listening preference.

Cheers, Joe

 

[jep123]

I have listened to the new Spec RSA M99 and it is a wonderful, highly musical integrated amp. This and the Spec top model are fabulous amps. Forget what you have read about Class D, Spec makes superb amps. But must be matched with some caution, these are not powerhouse amps. But gentle 8 Ohm loads and sens. about 90 DB and it is all very good!

Japanese quality build by tube lovers (no joke).

JP

 

[satbox]

The opamps are how they color the sound. That's why you see some Class D amp builders offering discrete op amp input stage choices like Sparkos (warm poo). Other opamps just sound compressed and lifeless. As to volume, you'll have to try and see. The advantage of the op amp input stage is its sky high input impedance. This makes the amp very easy to drive directly from your source. Does the spec sheet for the amp give an input impedance with the op amp bypassed? If it's still reasonably high, and your DAC isn't a wimpy driver, it should then be in the range of 6-8 dB or so. This is based on my memory of a Devialet input stage itself being capable of acting as a 4W amp. (Not that this is an option). Others should be similar, though if their configuration of the op amp is unity gain, i.e. a true buffer, then there would be no difference in volume. So let's say probably at most 6-8 dB.

Hi, Thank you for your answer!

 

[Kingrex]

I have been a tube guy for many years. Couple weeks ago a friend said buy the Allo Volt +D amp complete for $179 to my door. I laughed but bought it. I'm stunned. I have been happily listening for about 4 days now, kind of wondering do I need to plug my $11k in tube gear back in.