New review of the A21 amplifier - Good info!

[Chris D]

Here's a new review of the A21. I enjoyed reading this one, and really like the reviewer's perspectives on some things. Recommended reading.

http://www.soundreproduction.com/reviews/a21/a21_first.html

I found this line to be interesting:

I asked the Founder/CEO of Parasound, Richard Schram if there is a recommended burn-in period for the A 21 and was told that approximately 100 hours will bring out the most detail this amplifier is capable of producing.

That pretty much validates what we Halo owners were experiencing. Much better sonic performance over a break-in time.

The Concord Records sampler contains several performances by well-known artists such as Carol Sloane, Karrin Allyson, Dennis Rowland, Rosemary Clooney and others. Just about every track contains an intimate, small ensemble recording that brings tears to your eyes when listened to on a high resolution system. The A 21 did not stop the tears...I cried like a baby. That's what high-end audio is all about.

Wow, I could not agree more with this. There's a few of my favorite tunes/scenes that really impact me emotionally. Specifically, a few that come to mind are "Bad" by U2 from the Rattle and Hum DVD, "Hosanna Holy Holy" by renowned trumpeteer and gospel singer Phil Driscoll, and the launch scene from Apollo 13. (DTS) All three of those just compel me to crank up the volume to ear-bleeding levels. On a good system, they at the very least bring a lump to my throat. The Halo equipment really bring these material home.

[Peter Nielsen]

:T That review also has a great image of the A21 innards!

My major complaint about the A21 is the two gain controls that really do not serve any purpose when used with a modern preamp. I think that Parasound should do a "Mark II" release of the A21 that deletes the gain controls... :B

Peter

[r100gs]

:T That review also has a great image of the A21 innards!

My major complaint about the A21 is the two gain controls that really do not serve any purpose when used with a modern preamp. I think that Parasound should do a "Mark II" release of the A21 that deletes the gain controls... :B

Peter

I completely hate the gain controls. I've always had mine full on. When I bought a new CD player, I thought it was bad because a channel was dead. I was pissed because I gambled on some chinese import stuff. Come to find out, a cable had rapped around the the gained control, during install, and turned the channel off. Other than that I love my A21.

[nicholtl]

This was a fun review. The only problem I had with it (as well as most other audiophile reviews) is that he didn't review any sort of TRUE rock. And when I say true, I mean punk, metal, thrash, goth...

I mean come on. Michael Buble? Craig David? That doesn't test an amp!!!

[Peter Nielsen]

I mean punk, metal, thrash, goth...

:B :T :T :T Oh yeah! Motörhead, ACDC, Machine Head, Crowbar, and Ministry are some of my metal favorites... Not to mention old classics like Rush and Black Sabbath! Those were the days! ;b>

One of my favorite alterntives to rock is industrial music like Clan of Xymox, Frontline Assembly, etc. or the bands that mix the two like Rammstein.

Peter

[wildfire99]

So where should the gain controls on the A21 be set to? Full on?

[Chris D]

Yes, if you look at the rear panel, you'll see that corresponds to a position on the gain control knob that is labeled "THX Reference"

[MichiganMike]

I appear to be in the minority of owners that find the gain controls on the A21 useful. I have a low level hiss from my front speakers (Von Schweikert VR4Jr) when the gain is at maximum on my Parasound A21. Turning the gain on the A21 down slightly and raising the output from my Rotel RSP1068 to about +5 on the front channels gives me a significantly lower noise floor.

[J.H.]

You are correct sir. I have the HCA1205A Parasound amp and was getting hiss from all my speakers. I called Parasound and was told because my speakers are so sensitive that I should turn the gain down some and it worked no hiss anymore. The hiss was quite annoying by the way so I'm glad the amp has a gain control. J.H.

[Chris D]

Good point. However, since the A51 does not have gain controls, those with a A21 AND A51 (i.e. 7.1 setup) are kind of left somewhere inbetween.

[Peter Nielsen]

Good point. However, since the A51 does not have gain controls, those with a A21 AND A51 (i.e. 7.1 setup) are kind of left somewhere inbetween.

EXACTLY! That's why the gain controls on the A21 really make me feel like they do not belong there. Neither the A51 or JC1 has gain controls. Still these two amps are the two most likely ones to be combined with the A21...

Peter

[MichiganMike]

Chris, I am using both a Parasound A21 and A51. The Von Schweikert VR4Jr pair driven by the A21 at full gain had noticeably more hiss than the speakers driven by the A51 (Von Schweikert VR2 as center, Von Schweikert TS150 as side surrounds and Def Tech BPX in rear). Not surprisingly, the VR4Jr is rated as more sensitive than the VR2.
I reduced the gain on the A21 until the background noise from the VR4Jr with no source playing matched the VR2 center, then calibrated the system. It worked well for me. The hiss is now inaudible a couple feet from the VR4Jr, whereas prior to reducing the gain it was faintly audible from the nearest seating. In short, I am pleased to have gain controls on the A21, but do not need them on the A51. Your experience may differ.

[Chris D]

Good stuff, Mike. Matter of fact, this thread is inspiring me to try and turn down the gain on my A21 too, powering my Klipsch KLF-30 mains. Since my mains are calibrated to something ridiculous like -12db anyway, compared to something like -8 or so for the KLF-C7 center and so on, this could actually help.

I need to do a new calibration anyway, as I've done a bit of rearranging and cable swapping in my theater. (just changing around where I'm using various CAT cables)