Please tutor me on some integrated amp basics.


I’ve recently purchased Magico A3 speakers and a VPI Classic 2 SE turntable with an Ortofon Black 2M moving magnet cartridge. I have a Marantz SA 8005 CD/SACD player to play the few (maybe a hundred or so) CD’s in my possession.
I’ve mostly vinyl albums and no streaming sources. I’m next going to upgrade my old amp/preamp purchased back in the late 70’s with a new, probably integrated, one and am starting to do some research.

Here’s where I need some tutoring. A lot has changed since the seventies with the advent of digital technology. As well as I need to learn more about amplification components in the high end of audio technology. I keep running across terms I don’t understand. I’ll give you a list and if someone would be kind enough to explain these basics I’d be obliged.

For instance I was reading about the Hegel H360 integrated amp that Magico’s Alon Wolf recommended for their A3’s. The review mentioned they were a Class A/B amp, another person commented Class A’s were better, and a third person said he didn’t care for Class D amps. What do these classes signify? 

A second question is about DACs. I generally understand their purpose of the DAC, converting a digital to an analog signal. However my only digital device, the Marantz SA 8005 already has a DAC, ostensibly of good quality. The turntable ’s Ortofon cartridge would not need to play through a DAC, I presume. Would I bypass the CD’s players DAC if I purchase the higher quality Hegel H360 integrated amp?. Or could I find an equivalent integrated amp without an integral DAC?

On the other side of the equation I understand the turntable’s cartridge cannot play through the Hegel without first going through a phono stage. My old Phase Linear 4000 preamp you just plugged the turntables RCA cables into the back of the preamp and you were done. What’s that about? Do they make equivalent integrated amps to the Hegel H360 with integrated phono stages already in place, so I can just plug my turntable in as I’ve been able to do before. The amps don’t seem to be well integrated at all if you have to add a pricey phono stage to make them work, and end up having an extra DAC. That’s just me whining.

Third question is what are monoblocks, how are they used, and what are their advantages to a system? They were used at one of my speaker auditions.

I figured out the answer to what amplifier damping was myself, so I’m sparing you that one, but what does the term impedance mean? I keep coming across that.

Thank goodness I don’t have to figure out the cabling nightmare yet. Thanks for any help.

Mike
skyscraper
@skyscraper The Simaudio is a very nice unit, but I'm not sure it has enough oomph.  I would definitely add the Plinius to your list.  I just searchd "CSiB" on this forum and there were 64 hits.  Likely a number belong to the same threads.  Worth taking a look when you have some time...
You describe serious issues with power, Mike.

I have reasonably good power out of the wall, but even so I use Siemens in-panel surge protectors as well as isolation transformers. You could probably do with lightening arrestors as well. Talk to a local electrician.

The thing with isolation transformers is that they hum when they are doing their job, which is protecting your equipment. So they should be sited outside the listening room, perhaps beside a sub-panel. Plitron makes a good transformer, and they sell to the public.

Turntable add-ons are typically low power, so completely unsuitable for isolating an amplifier. TT motors are all over the map. Some are single phase, some are multiphase, some are DC. Multiphase and DC need their own controller, which can be as simple as a phase-shifting capacitor, but can be (and should be!) quite complex. A universal TT box might be a regenerator, or a constant voltage transformer, or just a few inductors and capacitors. In any case, unsuitable for an amplifier.

All power sources have imperfections, like a distorted sine wave for AC. The only question is how much. So if you are considering a regenerator, look for a picture of the "sine" wave produced, like an oscilloscope trace, and see how much it resembles the classic sine wave from your calculus text. Also look for specifications like total harmonic distortion (THD).

Considering your situation and your coming investment, I think that your first priority should be power conditioning. You are wise to think of it when most would not. Good luck!
One more thing about isolation transformers: they replace the need for lesser devices such as exotic power cords or regenerators.

I did the experiment years ago. 5 conditions: Isolation transformer alone VS isolation transformer plus exotic power cord VS isolation transformer plus regenerator  VS  regenerator alone VS  exotic power cord alone.

The results were: first three conditions indistinguishable, then a step down to regenerator alone, then a big step down to exotic power cord alone. This was good evidence that the isolation transformer made the big difference. The electrical inspector opined that the circuits protected by the isolation transformer provided power as clean as any he had ever seen, even at the power plants of major utilities.
terry9
The thing with isolation transformers is that they hum when they are doing their job, which is protecting your equipment.
More commonly, the hum is caused by DC on the line, or by a poorly designed or constructed transformer. I use a few different isolation transformers in my listening room - none of them hum.
For various reasons I decided the top contenders were the Hegel H360 and the Luxman L-507uXII. Both had superlative reviews.

The Hegel had Magico’s Alon Wolf’s recommendation for use with the Magico A3. It was rated at 400 watts into 4 ohms, a hundred watts over the Magico’s recommended top wattage of 300. That was substantially more powerful than the 210 watts into 4 ohms Luxman L-507uXII’s rating. The Hegel was Chinese in manufacture, Luxman had a preferable Japanese point of origin, and an exceptionally well made and solid build by all reports. The Luxmans wiring and internal components configuration looked well organized and orderly compared to the Hegels. As an indicator of the care taken in each products manufacturing, that helped tip the balance over to the Luxman in my eye.

The Hegel had a DAC I did not need, and lacked a integral phono-stage that I did, and would have had to purchase as a separate in addition.. The Hegel was more geared toward accommodating various electronic, downloaded music sources, the Luxman more the traditional analog turntable. The Luxman had a well reviewed mm/mc phono stage built in and no DAC. I hope lacking the DAC enabled Luxman to put more resources into the rest of the amp.

I ordered the Luxman for a hundred off list just a few minutes ago. Thanks for everyone’s help in making this decision and learning about integrated amps. Thanks Inna for bringing the Luxman to my attention. I did think about starting another thread asking about what others were using to power their Magicos. But I decided to skip it because I like Luxman’s longetivity and reputation, and their L-507uXII ’s design too much to pass it by. The Luxman looked built like a tank in addition to it’s superlative listener reviews. I like that. I don’t want to be dealing with breakdowns in the near or far future. My Japanese Toyotas certainly have that quality. Must be something cultural in Japan.

Next up, studying cables and power supply products. But that’s another thread.

Mike