USED - Parasound Halo A23+ Stereo Amplifier

This Halo Shines More Beautifully Than Ever

Parasound already brings listeners heavenly sound, but its halo now shines more beautifully than ever with its brand new version of the Halo A 23 two-channel power amplifier. Meet the Halo A 23+ and enjoy performance upgrades for cleaner, ultra-low distortion sound, revised front panel cosmetics, and a revised rear panel layout offering enhanced features, too.

"Together, the Parasound P 6 and A 23+ are dynamite," raves Roy Ervin Solstad, Stereo+ (Norway), January 2019. "Pure sonic magic with brilliant dynamics, delicious midrange and impressive resolution. To get such good sound for the price of this duo seems almost unnatural. One incredibly appealing preamp-amplifier package from Parasound."

Impressive Performance Upgrades

The performance upgrades are impressive, beginning with a big 25% to 30% increase in output power compared to the previous model. The A 23+ delivers 160 watts-per-channel at 8 ohms compared to 125 watts-per-channel for the A 23, 240 watts-per-channel compared to 225 watts-per-channel at 4 ohms, and 500 watts in bridged mono mode compared to 400 watts with the A 23.

The performance of a power amplifier is highly dependent on the quality of its power supply, and Parasound went the extra mile with the A 23+, which boasts a 10% to 15% larger main power transformer compared to the previous model A 23. Transformer size has been increased from 1.0 to 1.1kVA, and the filter capacitance increases 20-30% from 40,000 uF for the A 23 to 54,400 uF for the new A 23+. You'll hear the advantages of these upgrades as the A23+ presents lower distortion at full power.

Other performance upgrades include tweaked input circuits for improved crosstalk specs (70 dB at 20 kHz compared to 63 dB) and upgraded internal gold on gold audio connections, resulting in a cleaner signal path that's also more reliable.

Rear Panel Layout and Features Upgrades

The rear panel of the A 23+ has been revised in terms of layout and new features. It boasts upgraded speaker terminals, using identical terminals to the HINT 6 integrated amp, a new jack/terminal layout with more space and more clear text/labels, and a master "Vacation" AC switch. The 2.5mm trigger jacks of the A 23 have been replaced with 3.5mm jacks, and the audio trigger circuit has been updated for better low signal reliability.

Revised Halo Front Panel Cosmetics

The Halo series has always been known for its elegant aesthetics, and the look is even better than before. New front panel cosmetics include slim metal end caps replacing wider plastic end caps, an added gold metallic accent stripe along the end cap, gold feet now on black units, and an engraved metal "Parasound" badge replacing the red "P."

Advanced John Curl-Designed Circuitry

The circuitry of the A 23 was engineered by legendary audio designer John Curl. Its direct-coupled topology uses no capacitors or inductors in the signal path for pure, uncolored sound. Balanced inputs with discrete circuits and XLR connectors yield dead quiet operation. The complementary JFET input stage and MOSFET drive stage incorporates 12 beta-matched 15 amp, 60 MHz bipolar output transistors for pristine sound. The high-bias "Class A"/"Class AB" operation blends best sound with highest efficiency performance.

The A 23's custom-made, high-current power supply is specially designed for exceptionally quiet operation along with ample power for climactic music passages. The 1.1KVA encapsulated toroidal power transformer uses independent secondary windings for each channel along with a 54,400 µF power supply filter capacitance. DC servo and relay protection circuits keep operation safe and reliable. And Parasound backs the A 23+'s reliability with an impressive warranty.

No Need for a Remote

The front panel of the A 23+ looks great even when the unit is turned off. When you switch the Halo on, LEDs display AC-present, channel, and high temperature status. Adjustable signal sensing can be set to automatically power up the A23 when it receives a signal from your preamp or other compatible component (or when it receives a 12-volt trigger command), eliminating the need for yet another wireless remote!

'Instant Warm-up' Feature

Like all the other amps in the Halo product series, the A 23+ has Parasound's exclusive bias circuit, which permits the amplifier to sound perfect from the instant it's turned on, rather than having to wait for bias to gradually build up as the amp warms up over time. Even Halo's implementation of its automatic turn-on feature is exceptional. Special relays bypass the AC "soft start" circuitry after it's done its job for the purest AC and the purest sound.

Product Features

A23+ Performance Upgrades

Power up 25-30%
Filter capacitance up 20-30%
10-15% Larger main power transformer
Upgraded internal gold on gold audio connections (cleaner signal path and more reliable)
Tweaked input circuits for Improved Crosstalk specs
Improved power supply for lower distortion at full power
Filter capacitance: 54,400 uF
Transformer size: 1.1kVA

Revised Halo Front Panel Cosmetics

Slim metal end caps replace wider plastic end caps
Added gold metallic accent stripe along end cap
Engraved metal PARASOUND badge replaces the red P
Gold feet now on black units

Revised Rear Panel Layout and Features

Upgraded speaker terminals (A23+ gets HINT 6 terminals)
New jack/terminal layout with more space and more clear text/labels
2.5mm trigger jacks replaced with 3.5mm jacks
Audio trigger circuit has been updated for better low signal reliability
Master AC "vacation" switch on the rear panel

Product Specs

Power Output – Stereo Mode (0.06% THD)

160 watts x 2, 8Ω both channels driven
240 watts x 2, 4Ω both channels driven

Power Output – Bridged Mode (0.06% THD)

500 watts x 1, 8Ω
Bridged 4 Ω operation is not recommended

Power Output – Stereo Mode (0.9% THD)

210 watts x 2, 8Ω both channels driven
300 watts x 2, 4Ω both channels driven

Power Output – Bridged Mode (0.9% THD)

600 watts x 1, 8Ω
Bridged 4 Ω operation is not recommended
All Power measurement are at 120 VAC, RMS continuous power, full audio band (20 Hz - 20 kHz)

Current Capacity

45 amps peak, per channel

Slew Rate

> 130 volts per microsecond

Frequency Response

5Hz - 100kHz, +0/-3dB 20Hz - 20kHz, +0/-0.25dB

Total Harmonic Distortion (THD)

< 0.06% at full power
< 0.03% at typical listening levels

IM Distortion

< 0.04%

TIM

Unmeasurable

Interchannel Crosstalk

> 85dB at 1kHz
> 70dB at 20kHz

Input Impedance

Unbalanced: 33kΩ
Balanced: 66kΩ,(33kΩ per leg)

Total Gain

29dB

Input Sensitivity for 28.28V Output into 8 Ω

Unbalanced: 1 V
Balanced: 1V per leg

S/N Ratio

> 112dB, input shorted, IHF A-weighted
> 107dB, input shorted, unweighted

Damping Factor

> 800 at 20 Hz

Power Requirement

Standby: 1 Watt
Idle (no music playing): 75 Watts
Typical Listening levels: 3125 Watts
Maximum: 800 Watts

Physical

Width: 17-1/4"
Depth: 15”-1/4”
Depth, with cables 17”
Height, with feet: 4-1/8”
Height, without feet: 3-1/2”, 2U
Weight: 27 lbs.

Audio Advisor “Used” Product Warranty

What This Warranty Covers

This warranty covers defects in material and workmanship for used products purchased from Audio Advisor Inc. In the event your product fails, your sole remedy under this limited warranty shall be to return the product to Audio Advisor Inc. At the option of Audio Advisor Inc. the product will be repaired without charge for parts/labor or replaced.

Scope of Duration

The warranty period for "Used" condition units sold by Audio Advisor Inc. The warranty period for "Used” is one (1) year from date of purchase. These units have all been previously used and are specifically warrantied only for sales from Audio Advisor.

Shipping

You are responsible to pay for the safe and proper shipment of the warrantied product to Audio Advisor. Under this limited warranty, Audio Advisor will pay the cost of returning the repaired or replacement product to you.

What This Warranty Does Not Cover

This warranty does not cover damage due to: Failures arising from accident, catastrophe, misuse, neglect, or failure to properly connect and operate the Product in accordance with the accompanying instructions or specifications; Failures of any kind in Products which evidence any tampering, alteration, defacement of their serial numbers; Attempted servicing by anyone other than Audio Advisor; Failures arising from improper installation of the Product or incompatibility of other components in the system of which the Product is a part; Lack of routine maintenance; Connection to an improper voltage supply; Alterations or modification to the unit; Batteries or failure of or damage to Products caused by batteries; Fire, lightning, flood, "Acts of God", or other contingencies beyond the control of Audio Advisor Inc. Audio Advisor shall have no liability or obligation of any kind with respect to any of the foregoing types of failures.

Limitations on Persons and Products Covered

This warranty, and all rights provided hereunder, are limited to the original owner. In the event that the original owner transfers ownership of the Product prior to expiration of the applicable term stated in "Scope of Duration" above, this Warranty shall terminate in its entirety upon the date of such transfer. In no event will liability to you exceed the original purchase price of your unit. This warranty does not cover the cost of custom installation, customer instruction, setup adjustments, or signal reception problems. Consequential and incidental damages are not covered under this warranty. However, some states do not allow the exclusion or limitation of incidental or consequential damages, so this limitation or exclusion may not apply to you. In the event that your warrantied product cannot be repaired, Audio Advisor will either replace or refund the cost of the unit. We reserve the right to replace any out-of-stock, discontinued, or limited edition products with a comparable product. Discontinued products may not be available for warranty replacement.

Warranty Service Within North America

If you have a problem with your “Used” product purchase, Contact Audio Advisor at 1-800-942-0220. To receive warranty service, you must first obtain a Return Merchandise Authorization (RMA) number prior to returning any item. The RMA number must be on all returned items. If it is not clearly marked, Audio Advisor will return the package back to you, freight collect.

Packaging and Shipping

The original packaging should be used for the safe transit of your “Used” unit to the warranty repair center. You are responsible for the cost of shipping the product to the RMA designated repair center. You should insure the product for its full retail value in the event it gets lost or damaged in transit. Audio Advisor is not responsible for damage incurred during the transit of products sent to us. Shipping your product in non-factory packaging may void this warranty.

State Law

This warranty gives you specific legal rights. You may also have other rights, which vary from state to state.

Product Manual

	Parasound Halo A23+ Stereo Amplifier Manual (PDF Format)

	2019 Parasound Halo Product Line Brochure (PDF Format)

"Together, the Parasound P 6 and A 23+ are dynamite. Pure sonic magic with brilliant dynamics, delicious midrange and impressive resolution. To get such good sound for the price of this duo seems almost unnatural. One incredibly appealing preamp-amplifier package from Parasound."

- Roy Ervin Solstad, Stereo+ (Norway), January 2019

Parasound

USED - Parasound Halo A23+ Stereo Amplifier, Black