I was using a PIONEER SX 950 to run my Boston 901s. Good sound but needed more bass more heft if you will. I would hear "you need a sub". After hooking up this Amp and using the PIONEER as a pre-amp the difference was amazing. Now I was hearing, "where is the new sub"? Weight, depth, power. I love it.

None, runs very cool.

Picked up one of these pups off craigslist for $600. What a STEAL. I have had Teledyne AR9's for about 10 years and have tried a handful of expensive power amps (>350 watts into 4 ohms and in the $1,000 - $2000 range). These are my favorite. A slight warm sound HK is known for but very accurate. As most of the reviewers said, the thing that's really special about these is in the bass. When I first tested it out I actually thought it was bass shy, but that is just the lack of boominess or fake midbass. After a few demanding tracks I realized what the people were talking about. It gives the bass this "weight" that I have never heard before. And the acoustic suspension AR9s really benefit. The bass is soooo clean and loud even in the mid 20 hz range.

Everything

None

I had the opportunity to buy another of these amps, intending to use it as an extra for a 5.1 home theater set-up, whilst I kept the original in my usual stereo setup. By chance I bought a Citation 7.0 controller for this purpose, but out of curiousity I tested the amp in it's bridged mode.GOD!! I was astounded by the massive difference this has made, I was already flabbergasted by the change the original 1.5 had made to my system, but bridging it has put it in an almost different league. My speakers seem as if they are a completely different speaker, the definition,clarity in the bass,midrange and treble truly has to be heard! Never has my music ever sounded like this to me before! As I said in my previous review, i really need to get a pair of jbl 250ti's as I believe I will truly have arrived in Audio heaven then, as in my humble opinion you cannot get better than these 1.5 signature power amps. They truly are a sonic tour de force!!

Power, Clarity at High Volume levels. Bass definition to die for and ZERO distortion!

None

I bought this for what I consider a Steal! I had originally lost out on two bids on ebay for this amp, where they went for £630 and £700 pounds respectively so when I saw this for sale at Choice hi-fi with signature 1.3 ( 3 Channel amp) for £400 together I didn't hesitate to snap them up. Being a big fan of Harman Hardon amps over the years and originally I was after the Citation 22 as a power amp as I was intending to upgrade to the pre/power route after using various integrated amps over the years. But after reading a few of the reviews on here I thought I'd try my hands on the signature 1.5 if I could get one.
After getting my amp, the first thing I noticed( as with another reviewer here, my wife never notices when I change gear, but she did with this!) was the lack of any noise or distortion, it is so clear, the transformation is unbelievable, the bass is so much more extended and distortion free and this is at seriously loud volume levels, I'm lucky to live in a detached house with a fairly decent music room(27ft by 15.8ft) so I can get to explore the limits of this amp which I haven't even touched yet. The High's,Mids are perfect. I can't wait to get a pair of JBL 250ti's to really rock my house. I listen to a variety of music, Hip-hop, Jazz Fusion, R&B and Classical Jazz and this is the first amp I have had that gives justice to the music I play. The amp is built beautifully, weighs a ton(21KGs) and is built to last.If you can get one of these for even 3 times the price I paid, you'd still be getting a bargain. I will never need to get another power amp again,(except another one of these signatures, but I'd have to move to a bigger house)
My set is as follows, HK6950 used as pre-amp, Marantz CD7300 & Marantz CD72SE mk2, JBLSVA2100, (Harman Kardon TC55 but not wired up yet) and Audio Innovations Ultra 100 cable, the CD72se is connected up via Cambridge Audio AZUR interconnect.
It's a shame Harman Kardon no longer make Power amps of this Calibre again!

Similar Products Used:

Yamaha MX630, Marantz SM100, Sansui 9090, Harman Hardon 635 integrated, Harman Hardon Hk6950.

Clear sound, even at a high volume. Plenty of power, and a robut and reliable amp.

None that I could find.

This Amp was the first high end piece of equipment I ever bought, and from the moment I connected it, then to my old mediocre stereo, the sound was a definite improvement. But instead of stopping there I really got into the whole Hifi audiophile thing, and after 2 weeks after buying this amp, I also bought the HK 1.0 Signature Pre/amp that goes along with this. And what can I say, the two just complement each other like they were meant to be one piece of stereo equipment. When I got around to purchasing Quadral Vulkan high end speakers, the sound quality improved considerably, compared to my old stereo.
Now the sound is crystal clear, and the bass is there whenever needed.
Since I am a big Heavy Metal fan, I believe that one really needs a clear sound for this music and on top of that plenty of power, and believe me power is what this amp is all about. I mean, I have never been able to turn this amp up higher than 1/3 of the volume control indicator, simply because I'm afraid that the tweeters on my precious Quadral speakers might blow. Nonetheless, the sound has, even when turned up, never been distorted in any way. Actually, I'm also using an old 80s Technics equalizer (SH 8065), where I really pushed up the high range frequencies, so that everything is louder, than without its use. This thing again enhanced the sound qualities of my stereo by a lot, since it has 33 different frequency controls per channel.
All in all, I can only say that I am gald that I got this amp (as well as the 1.0 pre-amp that goes along with it from HK). If clear sound and power is the thing you're aiming for, then you simply can't go wrong with this power house of an amp.

Customer Service

Never had to use it !

Similar Products Used:

Harmon Kardon Pre-amp 1.0 Signature, that was designed to go along with this amplifier.

Power, bass control, build quality, nice minimalist design

They stopped making them

It all started when I began building a pair of Eton 11.2 three-way speakers. I didn't think that I was doing them justice by powering them up via my rock-solid but underpowered Sony STR-DA777ES receiver, and so began my search for a sub-$1000 solid state stereo amplifier with at least 200 wpc. Although I have a HK AVR 310 receiver in a vacation home, I wasn't really thinking about them in my search for a quality-but-inexpensive separate, until I read some of the reviews on this site. I verified the Signature 1.5's specs on Harman's website (http://manuals.harman.com/HK/Owner%27s%20Manual/SIGNATURE%201-5%20om.pdf) and thought that if I could find one, that it might fit the bill. After one month, does it ever. Effortless power, and controls the base very well in my Eton 11.2s, which have 11" woofers. Build quality seems quite good, made in USA, big toroidal transformer, about 66000uf of storage via 8 capacitors, all told 47 lbs. out of the box (another good sign IMHO). Nice 12v trigger in the back, and all kinds of protection circuity according to the manual. I would buy another one and run them bridged, at which point I've got 650 watts per stereo channel, but alas, the downturn and Harman's decision to leave the market for high-quality/value stereo separates to others makes this model an endangered species. My second choice was the NAD 218THX, which DMC has for slightly more money, followed by the Rotel RB-1090, but that's more than I need or needed to spend.

Similar Products Used:

Rotel RB-1090, NAD 218THX

Pushes my Maggies with athourity,lots of bass.You can always sell it and get what you originally paid for it.

I took a chance and purchased this amp to power a set of Magnepan MGllla's. Anyone that knows something about high end audio, knows how difficult it is to power these puppies,(4ohms). To my suprise, the 1.5 makes these speakers sound really good, even at low volumes. There are a lot of audiophiles that would shun their noses to this amp with the maggies. They sound really good with this amp. I can't write a review that compares this amp with higher end stuff, because this is the highest that I've owned. I've heard others like: Mcintosh, Mark Levinson, etc, in show rooms, but most things sound good in controlled surroundings. I would recommend this amp to anyone starting out in highend. Let your ears judge. Listen to the Music

Similar Products Used:

Used only other HK equipment

Solid analog construct with a huge toriod in the power supply.

none

This amp has incredible power I use it bridged for 650 w 8 ohms it is driving a 12" Jbl subwoover in a huge enclosure. It provides my home theater system with thunderous base. It gives a hole new meaning to the Bump"

Similar Products Used:

Harmon Avr 7000 Bought at a Harman outlet store in Oxnard Ca. for $800

power,power,power...and clean power at that.

no gain...no controls at all....only a problem if you dont have a good pre-amp

I love the clean power it delivers. I use it for the 2 subs I have in my home theater, and it can really shake things up. I cant imagine why anyone with quality, efficient, cone drivers would need more than this delivers (per channel. bi amping not withstanding)
overall a good quality powerful amp.
a bit pricey.

Similar Products Used:

sig. 2.0

Crystal sound, stock of capacity, fine choice for a domestic cinema and for music

It is not noticed

Surprisingly pure(clean), air, transparent sound will easily be coordinated to any acoustics.
I use with Mirage 1090is

Similar Products Used:

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