Parasound NewClassic 2125 v.2 Two-Channel Power Amplifier

One Hundred and Fifty Watts That Hold Their Nerve

The NewClassic 2125 v.2 is built for the system that has to work as well as sound good. It makes 150 watts per channel into 8 ohms and 225 into 4, in a chassis 17-1/4 inches wide and 4-1/4 high, so it fits a rack shelf without dominating it.

What sets it apart from a plain stereo amp is the load switch. Set it to the 2 to 3 ohm position and the amplifier holds 225 watts per channel into a 2 ohm load, which is where difficult speakers and long distributed runs usually defeat an amplifier this size.

Bridged to mono it makes 400 watts into 8 ohms, and it can drive 35 amps of peak current per channel. That is the headroom that keeps transients intact when the music suddenly asks for everything at once.

Inside the Chassis

It is a fully discrete Class-AB design. Signal-to-noise measures 114dB A-weighted at rated output, IM distortion 0.05%, and transient IM distortion is listed as not measurable. Response runs 20Hz to 50kHz at −3dB.

Input impedance is 33k ohms, with sensitivity of 1 volt in for 28.28 volts out. It weighs 27 pounds and measures 14 inches deep for the chassis alone, or about 16 with cables connected, which is the figure to plan a cabinet around.

Parasound covers the 2125 v.2 with a 2-year parts and labor warranty for the original purchaser from an authorized dealer. That is shorter than the 5 years on the Halo amplifiers, and worth knowing before you compare the two on price alone.

Who Is This Amplifier Best For?

• Your speakers dip low in impedance — the load switch holds 225 watts per channel into 2 ohms, so a speaker that punishes ordinary amplifiers stops being the reason your system sounds thin.
• You are building into a rack — 17-1/4 inches wide and 4-1/4 high with feet, at 27 pounds, so it shares a cabinet with other components rather than demanding a shelf of its own.
• You want the option of more — bridged to mono it makes 400 watts into 8 ohms, so a second unit doubles the system rather than replacing what you already bought.
• Your system switches on by itself — 12V trigger with a looping output, or audio-signal sensing, so the amplifier follows the rest of the rack without a separate switch.
• You do not own a preamplifier yet — this is a power amplifier, with no volume control and no input switching. Choose a partner from our preamplifiers and the two together make a system.

How Does It Connect to Your System?

Feed it from your preamplifier or processor by RCA. Speakers go to the binding posts. If your speakers drop toward 2 ohms, set the load switch to the 2 to 3 ohm position before you play anything.

For turn-on, use the 12V trigger with its looping output to chain other components, or let audio-signal sensing bring it up on its own.

Pairs Well With

Here are some great companions:

• Preamplifier: Required, and the natural next decision — see our Preamplifiers.
• Speaker Cables: Carry the current properly — see our Speaker Cables.
• Interconnects: Balanced XLR is the better run from preamp to amp — see our Interconnect Cables.
• Audio Rack: Give a Class A/AB amplifier air around it — see our Audio Racks.

Frequently Asked Questions

How much power does it make?

150 watts per channel into 8 ohms and 225 into 4 ohms. With the load switch set to 2 to 3 ohms, it holds 225 watts per channel into 2 ohms.

What does the load switch do?

It reconfigures the amplifier for low-impedance speakers, so it can hold its output into a 2 ohm load instead of protecting itself.

Can I bridge it to mono?

Yes. Bridged, it makes 400 watts into 8 ohms, or 400 into 4 ohms with the load switch set.

How does it turn on?

Manually, by 12V trigger with a looping output for chaining components, or by audio-signal sensing.

How deep is it?

The chassis is 14 inches, 15 including the speaker terminals, and about 16 once cables are connected. Plan the cabinet around 16.

What warranty does it carry?

Parasound covers it with a 2-year parts and labor warranty for the original purchaser from an authorized dealer.

See It in Action

OldTrades reviews the 2125 v.2 and what its THX Ultra 2 certification actually covers:

An unboxing, so you can see the chassis and the connections before it arrives:

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