ARCAM HDA SA20 Integrated stereo amplifier 90W

The design of the HDA range draws upon all of Arcam’s experience as one of the UK’s most respected audio companies, to produce Arcam’s best performing range of audio products yet – using the best quality components and engineering practices, the HDA range is designed and built to give you years of listening enjoyment.

• Class G amplification for impeccable sound and efficiency
• 90W of power per channel
• 5 analogue inputs including phono
• 3 digital inputs
• 32-bit DAC,Sabre ESS9038K2M
• Full I/P control
• Total harmonic distortion + noise = 0.003%

There are two frequent problems with hi-fi amplifiers. Class A, the traditional audiophile’s choice, uses a single power supply constantly running at full capacity, even when there’s no signal coming through. Great for reproducing those subtle details at low levels however struggles to provide extreme power when needed.

Class A/B, the most common amp class, switches between the two internal amplifiers, one for each half of the waveform. Far more efficient but often a recipe for crossover distortion, since those low-level details we crave can get lost within any mis-match between the two switching over.

Class G is essentially a hybrid amplifier, utilising Class A specifically for low-level signals, but when required switching in an additional power supply to power those larger sections of the waveform.

Ti 120 SIGN.
Special power and output transformer
from BHS uk and Mundof M-Cap
signal capasitors
Integrated tube amp.Four line inputs.
2X12AU7, 4x KT 88, 2x12AX7
2x6SN7 75 Wrms per chan.4-8 ohm.
Class AB push-pull.Remote control inc.
Negative feedback on/of switch.

Τi 60 tube
Integrated tube amp.Four line inputs.
2X12AU7, 4x EL34, 1x12AX7
35 Wrms per chan.4-8 ohm.
Class AB push-pull
Remote control included.

Choosing the DAC

Both our CXA60 and CXA80 amplifiers employ the same Wolfson WM8740 DAC, and thereʼs a very good reason for that: it sounds superb! There are more recent Wolfson DACs in circulation, however none sound quite as great as the WM8740 in our view. Which is why, time and again, we choose them.

The CXA80 utilises two separate windings on the oversize toroidal transformer. In effect, this is like having two toroidal transformers wound onto one chassis, providing separate windings for each amplification module. If you get a huge transient in the right channel, it wonʼt unsettle whatʼs going on in the left. The current is being drawn from a different path, rather than a common path, so the output is stable and remains unflustered, whether your liking is for Little Richard or Lamb of God.

The transistors used by the CXA80 are not your usual common or garden offerings. They come with an integrated Dynamic Thermal Tracking System. So what does this mean? Normally a Power Output transistor utilises a thermo-coupler attached directly to the heat sink of the amp; this informs the system so that it can rebias when key temperatures are reached. However, using Integrated Dynamic Thermal tracking provides a far more accurate reading of the real temperature of a transistor, and relays it faster too because itʼs not a delayed heating effect. This enables us to bias the amplifier more accurately and in almost real time. Which means your CXA80 is always running at optimum performance.

If you want to use a subwoofer as part of your speaker complement, the CXA80 doesnʼt penalise you for it. Because we want to ensure thereʼs no unnecessary high frequency noise affecting the subwoofer, weʼve put the output filter at 3KHz. This is high enough to prevent any phase shift associated with the low pass filter affecting what happens below 200Hz. The result is a phase linear subwoofer output signal which is clean and musical.

The CX range represents a step change in the way our engineers have approached signal path design, and the result is one of our most musical and entertaining amplifiers yet.

Previously, we went to almost surgical lengths to minimise distortion in order to get the best results. This invariably meant 46 components sat in the signal path. For the CX Series, we wanted to dramatically reduce that component count. The CXA80 now has only 24 components in the signal path. The big difference is that there are now 500 support components as well. Their job is to guarantee those 24 key components are absolutely optimal all the time, regardless of mains fluctuations and other influences.

This has made a big difference when it comes to tuning. Previously, tweaking one of the 46 components only made a small difference and it was sometimes difficult to quantify exactly what difference any change made. With the CX series, those 24 components have now actually become quite critical. Changing just one affects the character of the amplifier.We can hear very clearly what each of those components is doing.

This revision has fundamentally changed the character of the amplifier. Listening to a CX series amplifier is fun, engaging and exciting.

In order to offer 24-bit 192kHz resolution via asynchronous USB we use a specialist XMOS device dedicated to the USB input. Weʼve also written a custom driver to allow PC users to access the higher sample rates available in USB Audio 2 mode. This bespoke code allows us to stream audio files at the highest possible resolution.

If you want to use your CXA80 with a Bluetooth source, we offer an optional BT100 audio receiver. To ensure that this does not interfere with other components in the amplifier, itʼs isolated internally on the digital input board. From the ground up, this is an audiophile Bluetooth device. All the coding for the BT100, including the aptX implementation, is done in-house. We even include an extension cable which enables you get the best Bluetooth range.

Sometimes thereʼs a good reason to keep things uncomplicated. The CXA80 features a high-quality damped metal chassis, designed to ensure that nothing rattles or interferes with the electronics. Weʼve also kept volume control simple. The CXA80 uses a logarithmic ALPS pot. And when it comes to switching inputs, the CXA80 uses relay switching with silver plated contacts. This classic approach is still the best way to move signals around, rather than with transistors or electronic switches.

• Power output:80W RMS into 8 Ohms, 120W RMS into 4 Ohms
• DAC:Wolfson WM8740
• Frequency Response:

Toroidal Transformer

We mount the premium toroidal transformer centrally, to reduce flux or magnetic disturbance from the volume pot.

The output power transistors used by the CXA60 are not your usual common or garden offerings. They come with an integrated Dynamic Thermal Tracking System. So what does this mean? Normally a Power Output transistor utilises a thermo-coupler attached directly to the heat sink of the amp; this informs the system so that it can re-bias when key temperatures are reached. However, using Integrated Dynamic Thermal tracking provides a far more accurate reading of the real temperature of a transistor, and relays it faster too because itʼs not a delayed heating effect. This enables us to bias the amplifier more accurately and in almost real time. Which means your CXA60 is always running at optimum performance.

If you want to use a subwoofer as part of your speaker complement, the CXA60 doesnʼt penalise you for it. Because we want to ensure thereʼs no unnecessary high frequency noise affecting the subwoofer, weʼve put the output filter at 3kHz. This is high enough to prevent any phase shift associated with the low pass filter affecting what happens below 200Hz. The result is a phase linear subwoofer output signal which is clean and musical.

Thereʼs some revolutionary signal management happening beneath the lid of the CXA60. For the first time, our engineers decided to go fully balanced rather than single-ended all the way through. As a consequence, any noise that that might be picked up in the audio signal while routing through the amplifier is cancelled before itʼs output.

The CX range represents a step change in the way our engineers have approached signal path design, and the result is one of our most musical and entertaining amplifiers yet. Previously, we went to almost surgical lengths to minimise distortion in order to get the best results. This invariably meant 46 components sat in the signal path. For the CX Series, we wanted to dramatically reduce that component count. The CXA60 now has only 24 components in the signal path. The big difference is that there are now 500 support components as well.

Their job is to guarantee those 24 key components are absolutely optimal all the time, regardless of mains fluctuations and other influences. This has made a big difference when it comes to tuning. Previously, tweaking one of the 46 components only made a small difference and it was sometimes difficult to quantify exactly what difference any change made. With the CX series, those 24 components have now actually become quite critical. Changing just one affects the character of the amplifier. We can hear very clearly what each of those components is doing.

This revision has fundamentally changed the character of the amplifier. Listening to a CX series amplifier is fun, engaging and exciting.

If you want to use your CXA60 with a Bluetooth source, we offer an optional BT100 audio receiver. To ensure that this does not interfere with other components in the amplifier, itʼs isolated internally on the digital input board. From the ground up, this is an audiophile Bluetooth device. All the coding for the BT100 is done in-house. We even include an extension cable which enables you get the best Bluetooth range.

Sometimes thereʼs a good reason to keep things uncomplicated. The CXA60 features a high-quality damped metal chassis, designed to ensure that nothing rattles or interferes with the electronics. Weʼve also kept volume control simple. The CXA60 uses a logarithmic ALPS pot. And when it comes to switching inputs, the CXA60 uses relay switching with silver plated contacts. This classic approach is still the best way to move signals around, rather than with transistors or electronic switches.

• Power output:60W RMS into 8 Ohms, 90W RMS into 4 Ohms
• DAC:Wolfson WM8740
• Frequency Response:

Class XD™ amplification designed to eliminate crossover distortion at low signal levels
New balanced volume topology controllable in 1dB steps, giving very fine control, and superbly accurate channel balance
Audiophile grade oversize toroidal transformer and substantial extruded heatsink allowing 2 x 120 Watts RMS into 8 Ohms or 2 x 200W into 4 ohms.
Separate transformer taps for left and right channels, twin rectifiers and separate PSUs for dual mono operation of the left and right power amplifiers
A separate toroidal transformer supplies the preamp making the 851A effectively a Pre and Power amp combination in one box
CAP5 protection technology for trouble free operation
Acoustically damped full metal chassis with thick brushed aluminium front panel
Customisable front panel display
Balanced and unbalanced analogue audio inputs for superior connectivity
RS232 controllable
Eco-friendly Available in black and silver finishes