My HK 6550 integrated amp

[anm]

Disclaimer - As I have stated elsewhere, everywhere I am a person
- who enjoys music on all systems. There was very few decent systems that I hate.
- likes vocals more than instruments.
- I like bass. But not an overdose of it and certainly not loose, booming or humming bass, unless the musician intended to. Though I enjoyed a demo of JBL+HK floorstanders when it was playing hotel california - the bass was hitting my body like hammers and I really enjoyed it. But I doubt I can do that in my regular life at home. Though I may go there again once more for demo. Or may be several times.
- I am a fan of Hindi film music from 60s, 70s and some from 80s, specially Kishore Kumar. I also like Asha/ Lata/ Rafi/ Hemant Kumar/ Jagjeet Singh etc. I like some new hindi film songs as well. Kailash Kher too.
- I am getting into jazz music, Indian classical and other genres.
- I think I have good listening, though I am still learning how to classify my experience into warm, cold, bright, wide sound stage, 3D imaging etc.

My speakers - JBL n38, made in the US. Pretty cheap budget speakers in the US. Equivalent latest HK speakers cost 30k brand new though not sure if they are made in US or China.

Source - Right now it is analog out of philips 5986 DVDP. What! a DVDP? Viren too heard at it and thought I need a better source. Gain was too less he felt. However, I am having good time even with this source. I am looking for a decent source. It would be a CD player to start with, as soon as I can find one in my cheap budget, a turn table too pretty soon. But in long term it will be a hard disk based system - a dedicated music only computer. On lookout for rumored SqueezeBox touch. Archos also looks promising but didn't see many reviews from audiophiles.

I will use this thread to post my experiences in the long term. Maybe I will edit the main post itself from time to time.

Mods planned - pair with a lyrita pre. The pre is yet to be inserted in the path. Amp does have an "external processor out/ in" however, its own pre is not disabled when an external processor is inserted. I can still use the vol/ bass/ treble controls. Need to defeat it and use Lyrita pre directly with the power section. We opened the HK amp today at Viren's place and have kind of figured out how to mod it to use an external pre. It has separate boards for phono/ pre and power sections. Soldering of L/R and Ground into the power section should do the trick. Instead of using RCA jacks, we will take an Interconnect out to insert directly into the pre.

How I got it - Since I had scored a Lyrita pre, I was looking for a power amp. There were some very good amps that came my way (vincent that I think I was foolish to let go, but it was way beyond my original planned budget - but was not really out of the reach of my pocket). But somehow I was lost in finding opinions and reviews and couldn't settle for any. A forum member gave me the number of a used stuff dealer in Ghaziabad. Though he doesn't seem experienced at all, and sources his stuff from Chennai, which lot of people have branded as a place where you can easily get ripped off with junk stuff. But one day he called me saying he has some very good Nak AV-1 AVR and also some HK amp that I would not like due to its low power rating. I had earlier told him I want a power amp, pref 150-200 watts. I checked the internet reviews for 6550 and found very favorable review on tnt audio about it. So I thought, let me go there any see if it is worth even listening to, as it may be "chennai junk". But the dealer kept on saying "condition bahut saaf hai" (it is in a very clean condition).
He was hell bent on selling the nak, and I was only interested in the amp. Also, he insisted that I bring my speakers along so that I can make up my mind quickly. I said what the hell, but then I got hold of one of my cousin, put the speakers in the boot of my car. Speakers are decent size floor standers, but my car boot is the only thing that has great leg space so they fitted easily, with lot of space to spare, for their new partners maybe

So after driving for about 2 hours I reached this small shop where I was barely at a distance of 3 feet from speakers. When connected the amp with my speakers, and pushed the volume hard, I could see the woofers working very diligently, and obeyed their new master overzealously! I had never seen them move that much with my onkyo. Bass was quite good, and to my liking. Even of ear splitting volume both speakers and amp kept composure. And then I decided 50wpc is enough for me. Grab this one now! There were many interrupts, like the Nak AV-1 that kept interrupting like Shakti Kapoor between the love story of the JBL and HK 6550, long power cuts etc. but it rode back in my car along with my jbls. I started at 7pm from my home, and reached back at midnight! Was almost denied a dinner for this second hand used stuff hunting. Have you gone mad?

It is said that JBL + HK is a match made in heaven. Though Viren today pointed out that for this amp and speakers, this must be actually made in heaven rather than in factory, as HK acquired JBL much after this amp may have born.

To end today's write up - I like the sound very much. I just got some 20 new CDs today. Lot of them are hindi film music. Listening to those tracks I have listened to all my life, sound much better. Vocals are very good, and I am hearing lot of instruments for the first time (maybe because of my low-fi life earlier). Loved "nahin nahin koi tum sa haseen", "mujhe chho rahi hain" etc. I am right now listening to "disco station" and it has pretty good base and lot of instruments. I am loving it.

Oh - I also tried it today with Viren's single driver speakers, while Jagjeet Singh and Chitra were going around in circles on his Linn Sondek, connected to Lyrita phono pre, and then to HK6550 amp through external processor in.
It sounded pretty good. Viren also commented it is sounding very good so I take that comment as "it is sounding excellent". Great bargain!

I will keep on adding my impressions on this, as and when I get more music and change of source etc.

regards

 

[Sumit]

Hey Anm!!

Interesting write-up!!

And, I am glad the HK is working out for you. HK and JBL do sound good together. I have taken demo of this pair a few years ago. I also a demo of HK and Infinity which sounded good as well.

Sometimes you do get good deals in used market. One has to be patient.

Since, I keep coming to delhi for work and pleasure, I might pay u a visit someday Hope its okay.

Take it easy and enjoy the ride.

Sumit

 

[Asit]

Hi anm,

Let me first congratulate you on your recent acquisition of this Harman Kardon integrated stereo amp (HK6550).

As far as I can remember, these HK6550 amps were in production in 1992/93. So your amp is close to 17 years old. That's the only bad part, because with an unknown history, you never know what would happen to your amp, and how many more years.

As I said, that's the only bad part. The rest is all good, in fact, very good.

As many of you know, I have had the HK6300 amp, bought in 1989. Two years ago it went through a minor servicing, involving a few cap changes. This amp is still performing as if new and would beat many modern (ch)amps upto 1L or so. My amp (60 wpc@8Ohms)is capable of delivering up to 38 Amperes of current and has tremendous driving power and dynamics. It also has very open, transparent and clear sound.

Its bigger brother at that time HK6500 (70wpc@8Ohms) was a bit better in terms of tonality and was a multiple award winner at that time. Your HK6550 is supposed to be even better and one of the classic amps produced by HK.

Look at the following recent review and discussions at Harman Kardon HK6550 - Equipment Reviews and Tests - All things HiFI and AV - HiFi WigWam - HiFi Forum.

There have been statements like "Put simply, the HK6550 and other classic HK amps must be some of the best kept secrets in hifi. I think it is safe to say that this must rank as one of the finest amps I've ever had in my system, and it delivers the kind of performance that most people will find hard to believe for the price point".

Another guy in the same discussion says, "... I dont know what I (personally) would have below 400 over a HK6550, Id recco. a 6550 over a Primare A20 Mk II (and that is a lovely amp), the only thing of interest to me would be an original Sugden A28, but then you majorly sacrifice power for finesse. What this old amp can do with a set of 1.3 Conts is truly eye watering. Shame really as its price will preclude from a lot of systems IMHO".

You have to remember these are recent comments (made in 2008) about the performance of an amp built in 1992/93.

I have seen in the 1980's in the US some of the HK integrated amps being partnered with top notch products like a Nakamichi Dragon and very very expensive man-sized electrostatic speakers. That's when I made up my mind about a HK amp and when I got my first post-doc job I assembled my system around the HK amp and the Canton speakers. These amps are held in very high esteem even now in Germany and in the US. Very recently, as you know, the Leben CS300 has replaced the HK6300 as the main amp in my system.

I would think your amp is begging to be partnered with top notch sources and really good speakers. It can easily take quite high end speakers, and I mean it (with due respect to your JBLs, these are no match for your amp, not even close). Needless to say, very good quality speaker cables and IC's are also a must.

I know all this is expensive. But the reason I am saying all this is that : please have no doubt about the capabilities of this amp (my only doubt is about its history and how long it would last). Try to partner it with the best that you can have at a given point of time. Please do not treat it shabbily. Give it some honour and respect it deserves and it will deliver commensurately.

All the very best to you with this amp.

Regards.

 

[Sumit]

Hey Asit / ANM!!

Asit>Wow! You seem to know so much about this amp. I had no idea that it was this good. I would like to test this out...for knowledge sake. Not disapproving your claim here.

Anm, I own a NAD pre/power and PSB T55. I invite you to come to my place with your amp. Lets see what HK's got. What say?

HK Vs NAD? Wat say Asit?
And, anm will also get to know if it is worth spending on better source/speakers etc.

Also, ANM...whats ur name buddy?

Sumit

 

[Asit]

Hi Sumit,

I did own an entry level C325bee amp for a brief period. This I bought when my HK amp went for servicing. The Nad with their 3020 amp created quite a stir in the audio community and I was always eager to know more about Nads. I even heard their cassette player in the 80's.

Of course my 325 would be no match to your Nad pre/power, but I have heard a few other Nad integrateds and I think I can say a few things about the difference in the sound signatures of these old HK amps and the modern Nad amps.

Please remember these comments do not reflect my impression on the modern HK amps, because I have not heard them and have no idea whether their quality has diluted.

Assuming anm's amp is still in good condition, the HK would be very clean sounding, very detailed and very dynamic amp; while the Nad is well known not to be as transparent and clean sounding and details will be less. The Nads are also reasonably dynamic, but not as much as the HK. The HK will also beat the Nad on the high end details.

The Nad will be better in soundstaging, based on my experience. The presence of bass also will be more, modulo lack of a bit of details. The HK sound is a bit leaner compared with the Nads which have a fuller tonality. The Nads will be much more forgiving to poorer recordings. However, they make a quite a musical package despite their relative lack of details and this is the reason they offer an attractive package. With certain recordings(in my opinion, poor recordings), the HK on the other hand can sound quite impolite.

I would be eager to know if my speculations above hold up when you guys do the actual comparison. I am no pundit and of course can be wrong.

Also, remember, I am not telling anm to immediately run out and buy very expensive equipments to pair with the HK, because of two reasons, 1) I am not sure of the condition his amp is in (if you ever come to Kolkata, you are welcome to come and listen to my 20 year old HK and have some idea of an old HK amp running more or less in okay condition) and how long it would last, 2) it is not an economically and practically feasible option.

I just wanted him to be aware of the amp that he has bought, and if possible and whenever an economic option of an better equipment shows up, he has now a better reason to consider it. Basically I want him to be a proud owner of the amp, without being as non-patronizing as possible on my part.

I have not completely understood anm's thinking when he already bought a Lyrita pre and then went out and bought an integrated amp which does not have an input to the power amp section.

Regards.

 

[afj]

anm
let me start by saying that some people swear by hk amps and are extremely happy with their performance for music. i owned a hk 3480, listened to the hk 3490 and also the hk avr (cant remember the model). on all of them i've found that they just dont play stereo music well. what i like about it is the lows (its really tight and forward). the lower highs are sweet. but apart from that i couldnt find anything else to like. the upper highs are bright, the mids are muddy, quite disjointed in the reproduction and not musical at all. and i've played the 3480 with jbl L890s (which is quite a nice speaker by the way). i was so unhappy with the 3480 that i put it up for sale immediately after i bought it (i couldnt audition and bought off reviews and reputation). your view?

 

[Sumit]

Asit!!

Interesting thoughts. I would like to test NAD vs HK now--more than ever.

Sumit.

Hi Sumit,

I did own an entry level C325bee amp for a brief period. This I bought when my HK amp went for servicing. The Nad with their 3020 amp created quite a stir in the audio community and I was always eager to know more about Nads. I even heard their cassette player in the 80's.

Of course my 325 would be no match to your Nad pre/power, but I have heard a few other Nad integrateds and I think I can say a few things about the difference in the sound signatures of these old HK amps and the modern Nad amps.

Please remember these comments do not reflect my impression on the modern HK amps, because I have not heard them and have no idea whether their quality has diluted.

Assuming anm's amp is still in good condition, the HK would be very clean sounding, very detailed and very dynamic amp; while the Nad is well known not to be as transparent and clean sounding and details will be less. The Nads are also reasonably dynamic, but not as much as the HK. The HK will also beat the Nad on the high end details.

The Nad will be better in soundstaging, based on my experience. The presence of bass also will be more, modulo lack of a bit of details. The HK sound is a bit leaner compared with the Nads which have a fuller tonality. The Nads will be much more forgiving to poorer recordings. However, they make a quite a musical package despite their relative lack of details and this is the reason they offer an attractive package. With certain recordings(in my opinion, poor recordings), the HK on the other hand can sound quite impolite.

I would be eager to know if my speculations above hold up when you guys do the actual comparison. I am no pundit and of course can be wrong.

Also, remember, I am not telling anm to immediately run out and buy very expensive equipments to pair with the HK, because of two reasons, 1) I am not sure of the condition his amp is in (if you ever come to Kolkata, you are welcome to come and listen to my 20 year old HK and have some idea of an old HK amp running more or less in okay condition) and how long it would last, 2) it is not an economically and practically feasible option.

I just wanted him to be aware of the amp that he has bought, and if possible and whenever an economic option of an better equipment shows up, he has now a better reason to consider it. Basically I want him to be a proud owner of the amp, without being as non-patronizing as possible on my part.

I have not completely understood anm's thinking when he already bought a Lyrita pre and then went out and bought an integrated amp which does not have an input to the power amp section.

Regards.

 

[anm]

Thanks for all your responses. My name is Anant.

Why I purchased it even when I had a lyrita pre, and was looking for a power amp? I am a gadget lover, that's one small reason.

Part of the reason was the pedigree of this hk amp that I read on internet, large part was low cost (9k inr), big part was the condition - it is as good and clean as brand new on the exterior. Even on the interior, I was not able to see any thing wrong with my so inexperienced eyes. But I showed it to the doctor, Viren, yesterday and he too thinks the internals are in pretty decent condition. But the biggest reason was I liked its sound, though I tested only with my JBLs.

Another reason was that I was quite sure it should be easy to mod it to use its power section. It has external processor in, that can also be used with a tube pre amp, but the sound still goes through the pre section of hk. On a first inspection with Viren, we saw that the pre board was completely different from power board and the signal out from pre is soldered onto power. Which means it is a very simple mod. Looking around to find manual/ schematics to ensure our assumption is right, before going for the kill. Measure twice cut once The beauty of this mod (should be) that if I want to use lyrita, I can use it, and if I don't the pre to power soldering will still be there so I need to connect the source directly to the amp.
One thing to mention here, off topic, it is VERY pleasing to interact with Viren and he gives a very genuine opinion, even if it means no sale for his own equipment.

HKvs NAD - I am all for it. I have no emotional attachment to the amp so I won't mind if it is trashed by NAD.

Sumit - you are most welcome to give a visit. Where exactly do you live? In Meerut?

Also, I am more of a gadget man that the "ultimate" sound quality freak. Not that I like to change my cell phone every month, but I like to own gadgets and like to learn/ read about them. I also like gadgets that are fantastic value for money. I started with surround onkyo, then this solid state/ hybrid system and soon will add a valve/ single driver system from Lyrita. Waiting for that elusive bonus

Also - I would personally like to get deeper and compare (and own) several systems, amps and speakers. Used is a cost effective way to satisfy this urge.

Speakers - now that I have the amp, I may carry it around to find better speakers, or do some home auditioning if possible.

First upgrade will be on source/ sources.

I just wanted him to be aware of the amp that he has bought, and if possible and whenever an economic option of an better equipment shows up, he has now a better reason to consider it. Basically I want him to be a proud owner of the amp, without being as non-patronizing as possible on my part.

As Asit said, now that I have a decent sounding system, whatever I spend a serious amount of money, I would at least know what I am paying for.

 

[anm]

oh, I forgot, one of the big reasons was Asit's feedback on his HK amp - so though everyone trashes HK in this forum, I was sure it doesn't have to be necessarily true. It did deserve an audition at least. At least not many people here know about hk amps from past. I did exchange some PMs with Asit about this amp.

 

[anm]

hey afj, what is your current setup? Do you have the L890 speakers?

regards

anm
let me start by saying that some people swear by hk amps and are extremely happy with their performance for music. i owned a hk 3480, listened to the hk 3490 and also the hk avr (cant remember the model). on all of them i've found that they just dont play stereo music well. what i like about it is the lows (its really tight and forward). the lower highs are sweet. but apart from that i couldnt find anything else to like. the upper highs are bright, the mids are muddy, quite disjointed in the reproduction and not musical at all. and i've played the 3480 with jbl L890s (which is quite a nice speaker by the way). i was so unhappy with the 3480 that i put it up for sale immediately after i bought it (i couldnt audition and bought off reviews and reputation). your view?

 

[qoolss]

hey afj, what is your current setup? Do you have the L890 speakers?

regards

ANM, i must say you are one lucky fella. I had this amp for more then 5 years. I bought it from a germany online shop and can vouch for this amp anyday. the bass, trble along with subsonic filter and bi-amping this amp is one maching which is absolute quality. by the way for information sake, this amp was designed and manufactured in Japan by legendary amp maker something called Kawamitchi no sure... but i must say till this day i regret selling it. I bought it for 275 and sold it for 250 after 5 years (can you believe that) don't loose this prestige amp as there are very few which can match the sound quality of this amp. I have a roksan kandy K2 but believe me I would still prefer HK. nonetheless, enjoy the quality machine mate.

regards,

swatantra

 

[afj]

hey afj, what is your current setup? Do you have the L890 speakers?

regards

sold the hk and the l890s. i currently have the ma rs6, nad c272 / t163, ca640c, nad t524 (dvd player). have just ordered a new amp - a hybrid (pre tube and power ss) from china. upto 30w class a amplification and upto 160w class a/b. should get it end of aug. i havent been able to listen to it but from reviews etc and people that i've chatted with its way better than the nad so i dont think i'll be making a mistake there. and it costs me the same

i did like the L890s. very clean sounding speakers with a lot of power. loved them for rock. but the rs6 scored a little over them in every dept, esp the highs (was a little scratchy on the l890s) and the rs6 was way more musical. with the kind of music that i listen to being a bit more mellow than i used to i chose the rs6

 

[anm]

How is the base compared in both? I found l890 to have much more refined base than es90 es100.
RS6 must be quite cheaper too. Pricing is one reason I do not like JBLs and HKs.

regards

sold the hk and the l890s. i currently have the ma rs6, nad c272 / t163, ca640c, nad t524 (dvd player). have just ordered a new amp - a hybrid (pre tube and power ss) from china. upto 30w class a amplification and upto 160w class a/b. should get it end of aug. i havent been able to listen to it but from reviews etc and people that i've chatted with its way better than the nad so i dont think i'll be making a mistake there. and it costs me the same

i did like the L890s. very clean sounding speakers with a lot of power. loved them for rock. but the rs6 scored a little over them in every dept, esp the highs (was a little scratchy on the l890s) and the rs6 was way more musical. with the kind of music that i listen to being a bit more mellow than i used to i chose the rs6

 

[afj]

How is the base compared in both? I found l890 to have much more refined base than es90 es100.
RS6 must be quite cheaper too. Pricing is one reason I do not like JBLs and HKs.

regards

the bass is bigger in the L890's but the rs6 is slightly tighter. mids are a lot more musical in the rs6 and highs sweeter. also better sound stage. though taking away nothing from the L890s. i enjoyed them thoroughly. and much more powerful than the rs6. when you crank it up you can feel the power. both are extremely neutral. the es series is terrible imo. boomy bass, muddy mids, no transparency in the highs - one of the worst speakers i've listened to for the price. bose is better than that.

rs6 was a bit cheaper. about 8-10k rupees i think. jbl and hk for some reason sells for quite a bit more when compared to the america. i think what i really dont like about the hk amps for music is the sound stage. very disjointed and doesnt put it together

 

[Nimanchev]

ANM, i must say you are one lucky fella. I had this amp for more then 5 years. I bought it from a germany online shop and can vouch for this amp anyday. the bass, trble along with subsonic filter and bi-amping this amp is one maching which is absolute quality. by the way for information sake, this amp was designed and manufactured in Japan by legendary amp maker something called Kawamitchi no sure... but i must say till this day i regret selling it. I bought it for 275 and sold it for 250 after 5 years (can you believe that) don't loose this prestige amp as there are very few which can match the sound quality of this amp. I have a roksan kandy K2 but believe me I would still prefer HK. nonetheless, enjoy the quality machine mate.

regards,

swatantra

Many thanks for this info, my good sir :clapping: I found the HK 6550 in a pawn shop in my country with a damaged volume knob, and they sold it fot just 73! A legendary skilled expert in my city repaired its transistors and put the stock ones, according to the technical sheet, for just 18, and now I have it too.My concern are what bookshelf speakers should I choose and I registered here, begging for your help, as you know the amp better than me.I know this amp is warm and I bought it, since I quite hate bright and harsh speakers, I like neutral sound.
I need bookshelf speakers that will have no problem sitting on my desk, some 5-10 cm from the rear wall and side shelfs.There is no chance for stands in my small room.I will also buy the Arcam rPac to improve sound from FLAC and 320 kbps .mp3 files.There are a few options for me.I went to audition Marantz PM6004 amp and Boston Acoustics A26, KEF Q100, Mordaunt-Short Aviano 2, Quadral Argentum 330, and I easily preffered the A26.I know Monitor Audio BX2 are legendary for their quality at their price and unfussy positioning.My other options are Acoustic Energy Radiance 1, Dali Lektor 1, Focal Chorus 705 and 706, Tannoy Revolution DC6, and I can order them online and cannot audition any of them...:sad:

 

[arc]

Hi all! I have a speakers Pioneer CS-E 420. It's 4-8 ohm impedance, 87db/w/1m sensitivity and 50W max input power. Is they will be compatible with HK 6550 amplifier?

 

[Shailesh Dhodia]

Can you please tell me how much did you pay for HK6500?

 

[Nimanchev]

Update - after spending a year, listening to my HK 6550, after trying various cables, speakers and 2 DACs from Arcam, I find the sound unclear in the highs, somewhat dull and muddy.I often have to turn the Treble knob all the way to the right.A service technician said that he had restored the right channel with the original Toshiba parts, after somebody else had it improperly serviced.
I have sold Arcam rPAC and got an incredible deal, and bought the Arcam RDAC + the Best of both worlds linear PSU from Squeeze upgrade.The difference in detail is big, the RDAC digs deeper, the sound is fuller and wider.Using Boston Acoustics A25 and vintage Technics SB-EH750 ( the latter connected with a single cable with another wire in the second input ), I still have to turn the Treble knot all the way right.Plugging in my Akg K450 is better, but they also need more treble.
The speakers cables are Atlas Hyper 2.0 + Asymmetrical interconnect, and Furutech Formula 2 USB cable.So, what could the treble problem be ? I do not like any highs in the music at all.Does the HK 6550 need an entire change of electrolytic capacitors ? I do not want to sell it for another vintage amp like the Sony ES.Or should I ?

 

[vmscbe1974]

Dear friends

I am going take a demo of HK 6550 for my turntable. It has had good reviews. This is solely for vinyl and cassette listening. So I need a review on what aspects to check before buying since the history is not known and how to check if the ic capacitors have been replaced and check for any flaws? kindly guide me.
Regards
Srinivasan.M