How do I choose a better amplifier?

Amplification is the heart of any system and to improve it, I suggest you focus on three main areas.

These can be broadly grouped into: reducing integration, obtaining better-engineered/built equipment, and better bang-per-buck, meaning pre-owned, older equipment. Let’s examine each of these.

Integration

Integration refers to the level of stuffing of a box of electronics with different functions. Let’s look at amplifiers for example. The simplest solution is called a receiver. This is a power amplifier, preamplifier and tuner, all in one box. Some are small and heavily compromised and these tend to be the most affordable. Others are epic and huge like this Sansui G-8000! These are less compromised but still compromised as compared to separating the elements.

One level less amplifier integration is to get rid of the radio, leaving you with an integrated amplifier – a combined preamplifier and power amplifier in a box. Examples include these two beauties and hundreds of others.

The least integrated and therefore best-performing amplifiers are separate preamplifier/power amplifier combinations, like my Accuphase C-280V and P-360 for example.

If there’s one takeaway here I want you to understand that integration is the enemy of performance. The best solutions are always the least integrated ones. So if you want to improve your amplification, reduce its level of integration.

Build & Engineering

I’ve written about this a lot over the years but there is no special new technology that makes a modern amplifier in 2023 any better than a vintage amplifier from the ’70s or ’80s. There are lots of reductions in build quality and engineering though that make the older gear often significantly more desirable, better performing and longer lasting.

In terms of design, engineering and build though, you want features like separate transformers for each channel, or even for different parts of the amplifier like the phono preamp for example. Output devices are important and MOSFETs often tend to sound warmer and smoother than bipolar devices, other things being equal. Balanced designs are preferable to single-ended ones an offer significant advantages technically and therefore sonically. Class A is also a highly desirable design feature and one I’ve written about separately.

Age

OK, so why do I go on about age in this context? Simply because back in the day, labour costs were lower, and engineering and manufacturing standards were less compromised by the search to build things more cheaply. I’m fortunate to have worked on most equipment from most of the major manufacturers over the years and without exception, I can draw a line through the changes in build quality and engineering and find a broad peak running from the mid-1970s through to the mid-1990s. In some cases, the design and quality were even higher back in the 1950s and 1960s.

Fidelity

Waveform fidelity can be considered the precision with which signals are amplified. Technically, this covers dynamic fidelity too, but it’s worth thinking of them separately, as it allows us to discuss great sounding low powered amplifiers, too. Waveform fidelity is ultimately determined by the quality of design and components used, how many corners are cut, or not cut etc.

Dynamic fidelity relates to the ability to replay the full dynamic range of the music and comes down to how many output devices there are and the rail voltages supplying them, amongst other things. To be able to reproduce the full range of sounds from soft to loud, within your listening envelope, and with the sensitivity of your speakers in mind as this is critical, a certain amplifier power output will be required.

Options

The easiest way forward for most owners of basic receivers and integrated amplifiers is to purchase a better integrated amplifier, like an Accuphase E-202 or E-303, Krell KAV-300i, Luxman L-550, Pioneer SA-9800, Sansui AU-919, Technics SU-V8, Yamaha CA-2010, and there are many, many others.

The very best way forward is a preamplifier/power amplifier combo, again, of which there are many. This will take up more space, but it is the ultimate solution and keeps small signal and large signal circuits largely separate. Wanna go super-ultimate? You’ll need two mono-bloc power amplifiers to go with your high-end preamplifier. The best bang per buck will always come from older gear.

Power

Regarding power, read this: https://liquidaudio.com.au/faq/are-low-power-amplifiers-acceptable-in-hi-fi-systems/ and this: https://liquidaudio.com.au/faq/how-important-is-it-to-match-amplifier-power-output-with-speaker-sensitivity/.

Power is important, there’s no getting away from that, but some of the very best-sounding amplifiers are lowish-powered class-A designs. They have dynamic limits that must be respected though and using one might require a tradeoff of improved fidelity for reduced dynamic capabilities, or more sensitive speakers.

Conventional speakers of around 87 – 89dB/Watt sensitivity will, in most cases, require around 100 Watts per channel to achieve moderate dynamic realism without clipping or compression in most environments. Low-level listening and high-sensitivity speakers change that picture, allowing for less power. Bigger rooms, less sensitive speakers and those that demand realistic sound pressure levels will require much more power.

Regarding amplifier types for different use cases, read this, and this.

What to Look Out For

In terms of what to look out for, this is heavily influenced by budget as this will include some features and exclude others.

• Avoid very low-powered stuff, except for low-level listening and/or very sensitive (ie non-standard) speakers
• Avoid very cheap stuff as you get what you pay for and really good gear is never cheap.
• Look for class-A amplifiers, MOSFET output devices, and seriously heavy equipment.
• Failing some of these, you still want the heaviest, most serious equipment you can afford. Good equipment is NEVER light.

Regarding equipment you currently own, maintaining gear you love is always worthwhile and spending money on it will improve it, if that work is done by a competent technician. Just keep in mind that, no matter what parts are installed, you cannot make a piece of basic gear into a high-end killer.

Most people should look to a significant equipment improvement, requiring a significant outlay. If budget is the overriding factor, I suggest saving and waiting until your budget allows for the purchase of equipment that significantly improves on your current amplifier.

Summary

1. Reduce integration, improve quality, engineering
2. For sonic improvements, you have to move forward, not sideways
3. To improve on a basic integrated amplifier, you need a better, more expensive design and less integration
4. Good advice is critical to making the right decisions, bad advice leads to the wrong ones.

Need More Advice?

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