Purchased in July 2014. The amp has been around for years. No 21.2, no 21ES.....just the same amp; and there is a reason. This has got to be the one giant killer of sustained value the audio world has ever seen. The power and circuitry are phenomenal. I have played this amp through the Rockport Altairs and the Odyssey Audio Kismet reference. In a word, the flow of music was so evolved and liquid....silky with abundant detail. John Curl is the reason, he designed a unit so evolved that Parasound could get twice the price for it and still be undervalued. Don't hesitate to buy, excellent with every speaker I tried including the Maggie 3.6s. Use the balanced inputs when possible, the filtered power is huge for dynamics and I could swear....it is class A beyond the first 10 watts. I had considered the Pass Labs Int 150, but after reading the review in Stereophile where what appeared to be a faulty unit was given a great review, I passed. Glad I did, I saved a ton of money and received an outstanding amplifier. Using the P5 for a pre-amp and it is as great as the amp is.

l bought the Parasound halo a21 and the differences of improvement in the sound quality are just unreal, it's like too good to be true, before the parasound i had an Emotiva XPA and after listened to the differences btw the emo and the parasound i got to the conclusion that emotiva made my speakers sounded so bad, the sound quality is night and day differences, I'm was shocked!! It's just unbelievable, to give you a better hint of what I'm talking about, the emotiva is a Honda and the Parasound is a mercedez Benz s63 AMG, or Toyota vs Ferrari lol. I can't believe the sound just can get that good.

Emotiva is not High End they not even close to what high end can sounds like, they are good products but never can consider high end, since they claim to be high end, for the price you can get a good sound, but they are out of the high end league, that's a true statement. it's not an opinion It's what it's, when i demo the parasound i put it side by side with 10,000$ and 12,000 dollars amplifiers and the emotiva just sounded as good as those super expensive amps.

The emotiva was my first amplifier so that's why i wrote a review saying that Emotiva was a truly High end Amp with a consumer price tag LOL, what the Hell i was thinking OMG i was soooooo wrong.

I was only getting 20% of my sonus faber veneres with the emotiva, now I believe I'm getting their full potential 100%, I believed the hype of the emotiva for a while, I was a believer but now i know emotiva is just a good mid-fi amp, nothing more!! If you looking for the best sound as possible please don't get the emotiva, emotiva is not even close to high end, you will be disappointed!! The parasound is the best High end AMP you can get for the money, i believe that you can spent the double of the money and won't get this kind of performance, Halo is the best Bang for your Buck and i finally found the product that i want to use forever.

to get a better understanding of what i'm talking about, let's say Parasound vs krell is like mercedez benz S Class AMG vs roll royce!!! all depends your budget and how much money you want to spent, but me personally i'm gonna stick with the parasound halo forever.

The A21 has got to be one of the best kept secrets ever. I bought it second hand for less than half the original retail price. Wonderful performance driving any speaker load, and I've run it with seven different speakers thus far, both conventional and planar.

The amp is like a diesel engine, pulling an incredible amount of low-end grunt from recordings where I had formerly never known it existed. It has been a tremendous pleasure going through my old dust covered disc collection discovering some real hidden gems I'm glad I hadn't discarded.

It is definitely a beast of an amp physically, and proper space is needed if that is a concern in your application. You'd better allow for about 22" of depth if you use XLR's.

I had a McIntosh MC7200 at the same time as the A21, and after over a year of comparison I sold the Mac. The A21 just trumped it in every way. Though I did like the blue VU meters on the Mac...

One small negative is the XLR sockets do not have a locking feature. Other than that this is one of the best amps available for the money bar none. Buying one second hand is a classic no-brainer. This one is a keeper.

Great soundstage, ability to drive inefficient speakers

very heavy at 60 pounds, puts out a lot of heat

The parasound Halo A21 is a heavy amplifier. Great quality looks and build, handles on the back and heat fins on the side, the blue lights look good at night. 250 watts per channel, it has plenty of power to run inefficient speakers, such as my JSE infininite slope 1.8 with 4 drivers. Using Cardas quadlink speaker and interconnect, this needs a good break in period and open cabinet where the heat can escape. After many hours of playback, the soundstage opened up with instruments heard in great detail. With 1.2 kVA encapsulated toroid power transformer with independent secondary windings for each channel , and 100,000 µF power supply filter capacitance , this amp delivers superb bass, this amp will never break a sweat! This one amp will outperform my 2 B&K ST202 put together in a bi-amped setup.

Similar Products Used:

B&K ST-202

Strong amp will drive nearly any speaker, especially inefficient ones

Very heavy, puts off alot of heat, so dont use this in an enclosed cabinet

The Parasound A21 is an extremely heavy amp weighing in at 60 pounds. It is rated for 250 watts per channel, 8 ohms. It is capable of running in mono mode, with balanced or unbalanced connections, and gain adjustments on the back. Great build quality, large handles on the rear (may be needed when moving this) and is deep at 22 inches, requiring a large and strong shelf.
Upon using the Parasound Halo A21 during the break-in period, I noticed the soundstage grow wide and deeper. This amp needs a good amount of time to break in, and produces a good amount of heat, since it runs class A for the first 10-15 watts or so. 1.2 kVA encapsulated toroid power transformer with independent secondary windings for each channel, 100,000 µF power supply filter capacitance allows for this amp to deliver sudden bass impact when needed without any strain whatsoever. This workhorse will compete with the best amps such as Pass or others costing thousands more.

Similar Products Used:

2 B&K ST 202 together, and one Halo A21 beats these amps out combined!

tight deep bass, sweet highs

It is heavy but it's worth the strain to move it into your rack

I had upgraded my speakers (PBN Audio Montana SPX) after listening to them in the shop powered by a set of Halo JC1 mono blocks. I got them home and hooked them up to my McIntosh 6 ch home theater amp ( 85/watts/ch ) which is not a bad amp but they were missnig something. I can not afford nor have the room for the mono blocks so my salesman suggested I try using the Halo A21. I brought the amp home hooked it up and there was the sound that I so loved in the showroom. I finally had a set of speakers that could produce everything on a recording and an amp that allowed my speakers to perform there best. The A21 had absolute control, no matter what volume I play the system at I never hear it become harsh or strained. I feel I am getting about 95% of the performance of the JC1 for a lot less cash. I don't think I have ever got this much bang for my audio buck before. On top of the A21's great performance I think it is a beautiful piece of equipment just sitting there in the rack with it's blue glow. This amps beauty is more then skin deep.

Similar Products Used:

McIntosh MC126

Hi end performance ,looks and build at a mid fi price. huge soundstage and deep bass will drive any loudspeaker.

none as of now

This is one serious amp.I cant believe Parasound can market this product for 2 large.I shopped at high end shops in the north Jersey area and they showed me amps at two times the price that could not shine the shoes of this beast.I recieved the amp via ups and they left it on my stoop while I was at work.No need to worry cause no ordinary thief was gonna be able to carry this piece of audio excellence away.Boxed up the weight was 77 lbs. I almost died draging it down the stairs to my listening room. The a-21 comes in a double box and at that weight it was a good thing.Putting it on the bottom of my equipment rack was a monumental chore,first this amp is 19' deep I had to slide the rack out 6" just to fit it in and the weght 60 lbs unboxed made me break out in a sweat.Once hooked up and turned on all was well worth it . This amp sounded broke in right out fo the box.It controlled my Infinity Renaissance 90"s with relative ease .The soundstage was huge,the bass deep tight and fast.the 90"s are not an easy speaker to drive and if you get the right amp the sound is exhillirating.I ve finally got the right amp,and i didnt have to take a second mortgage on my house. O.K. so the amp is made in Taiwan if you can get by that you have a great looking amp Designed by John Curl and put to market by a reputable american company with a 10year warranty what more can I say if you buy a mega buck amp its your lose I think Ill go buy some music with my savings.

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parasound p3 pre amp
Denon dvd 2800
Infinity Renassaince 90

NUMERO UNO: Competes with the best solid state amps out there at real people prices.

Outstanding 10 warranty. Dealt with Parasound service dept. on my PLD 1100 and they were amazing. Best electronics service I've ever encoutered.

Very sexy cosmetics.

Good Lord is this a great, great amplifier. The sonic prowess and downright agility this amp can muster with a dregree effortlessness is worthy of accolades.

You have a world class designer coupled to a company that's large enough to take advantage of economies of scale and deliver those savings to the consumer.

Thank You John Curl, Thank You Parasound! Finally, I've got the sound I've been after but could never justify the cost.

The A21 delivers the details alright, but with the sureness and a smoothless that I find captivating. Clean but not antiseptic.The music splashes but doesn't leave you wet. How's that?

Using this amp with killer Tyler Acoustic Linbook Monitors, PS audio solid copper cables, Audioquest King Cobra interconnects.

Recreates the entire audio spectrum well. Excells in the bass dept. Loads of power. Competes with(and beats) amps 3-4 times it's price. Nice build quality as well. May not do one thing perfectly but does it all very well.

Some might consider it's weight a weakness but that's reaching.

I have to completely agree with the other reviewers. The A21 provides world class sound at a mid-fi price. This was on my shortlist of amps 200 watts+. I got the upgrade bug and went for a Pass Labs X250.5. The Pass is a work of art and is a real brute. Throws the largest and widest soundstage of any amp I have owned and had tremendous bass slam but like most high end solid state, it is extremely hyper detailed in the upper frequencies. Now I'm not slamming Pass Labs. Nelson Pass has been in business far too long not to know what he's doing, but I personally feel that with his (and other's) upper echelon designs, everything has to be perfect (especially the recorded music) to get the best sound, and my CD collection is anything but. After the Pass, I decided to give a couple of the new digital amps a shot. I tried Henry Ho's H2O M500S amps. Effortless power but yet again too much of a good thing for me in the upper frequencies. IMO, a better overall amp than the Pass X250.5 sonically and at half of the X250's price.... Then I tried the Channel Islands D-200 monos. These were closer to what I was after. A more balanced sound from top to bottom. Still a little bright for my tastes. But at moderate to high volume they started to run out of juice, which caused distortion so back they went. Henry Ho and Dusty Vauter are definitely on to something with their own unique designs. Digital amplification is only in it's infancy and the future of digital amps sounds very promising, but they all could be a little more imaginitive in the looks dept. Especially Channel Islands. Fairly cheap build and design for the money. If I'm going to pay $2-3k for an amp, it should be a treat for the eyes as well as the ears. Then I tried the JC-1 monos. Without a doubt the best amps (tube or solid state) I have ever heard. Detailed without grain, excellent bass. Liquid, airy mids. Holographic soundstage. As close to the real thing that I have had in my listening room. Downside for me? I bought a pair of demos from Audio Advisor and they were complete basket cases. They would work for 10 minutes and shut down, so back they went. I couldn't afford a new pair of JC-1s so I finally decided to try out the JC-1's little brother, the A21. YES! Finally, a solid state amp I can happily live with. It's no lightweight, physically or sonically. Airy, detailed mids and highs like it's bigger brother. 3D soundstage with well recorded music and possibly even better bass slam than the JC-1s. IMO, you get 85-90% of the JC-1s at a quarter of the JC-1's price and buying a mint A21 used is a complete no-brainer. The A21 is a benchmark product that favorably competes with amps 3-4 times it's price, (including it's big brothers) has plenty of power and looks pretty good doing it. Definitely a keeper.

Similar Products Used:

Pass Labs X250.5
H2O M500S monos
Channel Island D-200 monos
Parasound JC-1 monos
Numerous others (Krell, Levinson )I have tried and owned over the years.

Great looks. High quality build. Natural realistic sound. Low price.

I can second all that has been written before me (two reviews), even though they sound to me like they were written by the PR dept. of Parasound. I have had two Threshold Amps, most recently the S500. Both were wonderful. I have been updating my system and thought to audition the A21 just for fun. I was blown away! I sit at the front of the Chicago Symphony Orchestra, so I'm used to live sound. . isn't that the goal. With this amp recordings that I've listened to for years seemed to be more revealing than ever before. Iniatially I thought the amp was overly bright until I changed to a better balanced cable. I use Transparent RCA's also. Both sound great! Punchy, natural, transparent, great sound stage, not too bright, and above all. . . .so real as to put you there with the artist. Highly recommended! And at this price. . . . .a huge steal.

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Threshold