Atoll IN100 Signature Integrated Amplifier, Silver

The Atoll IN100 Signature is an analogue stereo integrated amplifier with dual-mono power supply, delivering 2×100 watts at 8 ohms and expandable with phono and DAC cards.

Eleven kilograms, two toroidal transformers, no display – the IN100 Signature is the kind of amplifier you buy and then almost forget about, because it simply works every day.

Why the IN100 Signature?

Because it brings Atoll's core principles to the entry class: two 340 VA toroidal transformers (680 VA combined), 31,474 µF filter capacitance, a Class A/B design with a discrete preamp stage. Five line inputs and a home-cinema bypass cover everyday use, two pre-outs allow for a subwoofer or bi-amping later. And the AUX input turns into a phono input with a plug-in card.

What you hear

Power with manners. The bass stays controlled, the mids are clear, and the treble stays civilised even at higher levels. The 100 watts aren't a brochure number – at 4 ohms they climb to 140 watts instead of faltering. A headphone output with 6.35 mm jack sits on the front, a 12-volt trigger for automation at the back.

Who is the IN100 Signature for?

For a first proper system, or as a solid core in a normal living room – and for anyone who wants to start small and expand step by step. Plain talk: the remote control is an accessory and not included – that regularly surprises people, so we'd rather say it upfront. Streaming and digital inputs are missing out of the box, as is an XLR input. For very large rooms or hard-to-drive speakers, the IN200 Evolution is the more honest choice.

Our verdict

When we're asked to recommend an amplifier that lasts ten years and doesn't feel undersized after five, we often land here. Christian Rechenbach wrote about it in hifitest.de: «Der IN-100 ist ein Vollverstärker klassischer Schule, der jeder Anlage ein saubere Fundament liefert.» Which speakers do you have – or would you like? Call 044 680 22 00 or message us on WhatsApp at 076 534 22 00, we at HD Zürisee in Wädenswil will find the right combination.

Technical data

• Type: analogue stereo integrated amplifier, Class A/B, with dual-mono power supply
• Output power: 2 × 100 watts at 8 ohms, 2 × 140 watts at 4 ohms
• Power supply: 2 × 340 VA toroidal transformer (680 VA combined)
• Filter capacitance: 31,474 µF
• Analogue inputs: 5 × line RCA (AUX – switchable to phono card –, CD, tuner, DVD, tape with input and output), 1 × bypass
• Digital inputs: not from the factory – retrofittable via DA100 or DA200 option card
• Outputs: 1 pair speaker terminals, 2 × pre-out RCA, tape-out, 12-volt trigger
• Output level: pre-out regulated, tape-out fixed
• Headphone output: yes, 6.35 mm jack on the front
• Frequency response: 5 Hz – 100 kHz
• Distortion: under 0.05% at 1 kHz and 10 watts
• Signal-to-noise ratio: 100 dB(A)
• Input impedance: 357 kOhm, input sensitivity 100 mV
• Slew rate: 2.5 µs
• Option cards: phono P50 (MM) or P100 (MM/MC), D/A converter DA100 or DA200
• Remote control: optional, not included
• Housing: 4 mm brushed aluminium front
• Colour: Silver
• Dimensions (W × H × D): 440 × 95 × 305 mm
• Weight: 11 kg
• Warranty: 2 years
• Included: Atoll IN100 Signature, power cable, user manual

Frequently asked questions

Does the Atoll IN100 Signature come with a remote control?
No, the Atoll universal remote control is an accessory for the IN100 Signature and not included. You can order it separately – it then also controls the other Atoll devices in your chain.

How much power does the Atoll IN100 Signature have?
2×100 watts at 8 ohms and 2×140 watts at 4 ohms, supplied by two 340 VA toroidal transformers and 31,474 µF filter capacitance. That's plenty for living rooms up to around 30 square metres and speakers of normal sensitivity.

Can I connect a turntable to the IN100 Signature?
Yes, with a phono card. The P50 turns the AUX input into an MM input, the P100 can additionally handle MC with switchable termination impedance. Without a card, you connect an external phono preamp to one of the five line inputs.

Does the Atoll IN100 Signature have digital inputs?
Not from the factory. The DA100 and DA200 cards retrofit them: the DA100 with two coaxial and two optical inputs, the DA200 additionally with USB-B and Bluetooth. That turns the analogue amplifier into a hub for TV and computer.

Why buy the Atoll IN100 Signature from HD Zürisee?
Because with the right speakers, this amplifier plays surprisingly far above its price. We find the combination that makes the most of it, retrofit a phono or DAC card, and take care of delivery, installation and service with our own technician.

Goes well with

The natural partner is the Atoll CD100 Evolution from our CD players, plus bookshelf speakers or compact floorstanding speakers. A streamer and the right cables complete the chain.