About Harman/Kardon German amp versions

my best guess: it's just about some stupid german "high frequency interference regulations" these days...

Thank you very much, MM!

I suspected that was the reason back in 1991, but was not 100% sure.

Hi "Karl vd Berg",

sorry, if I may not have understood your question correctly, but you are showing schematics that are clearly not comparable. To which amplifier does the upper ("German model ") belong, and to which the lower one? Between a HK 6100 and a HK 6500 there are of course differences! You have marked the inputs; connect the 2SC2320L in both cases. Unfortunately, I cannot tell you what the difference between the leading circuits Q601 and Q602 is. - Do you know that as someone who asks such questions?

Dear CarlosDZ,

These are pieces of random schematics of both models. I was just interested in why - for German models only - there were/are added components (highlighted in blue). It was not about differences between the 2 models (HK6100 and HK6500), but rather the added circuitry for preventing RF noise, I believe.

User Mickey Mouse confirmed it.

These units sounds better than many vintage stuff, in my opinion. The only thing is that some of them do not have a proper relay protection for speakers, but anyway, thank you very much.

Hi Karl,

"Mickey mouse" is a commentator here whose opinion I very much appreciate! - Even more I appreciate the developers of the electrical circuits of a HK 6500 (or a HK 1200), a very excellent amplifier! They would not be able to control their craft, if through additional circuits especially for the German market ("German model") to prevent RF noise, when these additional circuits come to an even better sounding amplifier. That would mean that the amplifiers equipped for the German market with additional circuits for the prevention of RF noise sound best, and all others worse. No, I don't think it's stupid!
These are perhaps really additional circuits (for the German/European market), for the prevention of RF noise, or whatever. In my opinion, however, nothing that improves the sound. Otherwise it would always be built in. Or it would be bad engineers.
I admit that I am a HK 6500 fan; Do you have one to this amp a German, and an American schematic so that I can compare both?

Sincerely yours

Hi Carlos,

The schematics for the HK6500 are the same overall. You only have to include the components for the German version which are marked "(G)" in the schematics.

https://www.hifiengi...-kardon/hk6500.shtml

Both HK6500 and HK1200 use 2SC1775 differential at input. Really good transistors!

Regards.

Karl: I wouldn't really worry about the extra parts for improved electro-magnetic immunity (EMI) on the line-level I/Os - whereas in case of the phono input the extra capacitance can have some negative impact, depending on the cartridge. And yes, you'll also find similar differences in pre-amps, integrated amps and receivers from other manufacturers - and the general trend seems to be, that the newer the model, the more EU-wide or even worldwide the extra parts for improved EMI will be installed (probably due to generally increased EMI requirements, which would seem no wonder, given that the stuff nowadays has to cope with quite a bit more radiation from various sources (cordless phones, cell phones, WLAN, Bluetooth et cetera...)). For instance, extreme examples were the Marantz PM7000/8000/7200, the EU versions of which have 1150 pF installed on the phono input, where the other versions only have 150 pF, so that the MM input is practically unusable for anything but high output MCs (as well as a few MMs and MIs with very low inductance), unless one modifies it.


Carlos: Well, whether the improved blocking of electro-magnetic interference would improve the sound, would simply appear to be a question of whether there is such interference or rather not. As mentioned above, in case of line-level I/Os it's usually unproblematic, so I wouldn't worry about it. But it case of the phono inputs some manufacturers really have gone too far: If an MM input has such excessive capacity, that it's not hifi-capable in combination with typical MM and MI cartridges anymore, one might perhaps deem that tolerable in case of something like a mini-system, but certainly not in case of hifi pre-amps, integrated amps and receivers.


Greetings from Munich!

Manfred / lini

Thanks, Manfred.

You are right, nowadays we have a lot more stuff connected to same electric network. I hope there will be other ways to clean up noise/interference from busy 230VAC mains without adding extra components to the input stages.

Regards.

Hi "lini",

wir Beide können ja "auf Deutsch" miteinander - hoffe ich: NATÜRLICH entwickelt man als globales Unternehmen seine Produkte auch global; die "Toleranz" dabei, dass dem Einen dies oder das nicht ganz PERFEKT erscheint - dem Anderen vielleicht aber durchaus - , würde ich deshalb als "Streuung" bezeichnen.

Zu bemerken bitte ich Dich, dass gerade der Phono-Eingang beim HK 6500 / HK 1200 - hier in Deutschland - i.d.R. als "sehr gut" beurteilt wird. Im übrigen unterhalten wir uns - beim HK 6500 jedenfalls - über einen Verstärker Ende der 1980ger des letzten Jahrhunderts; für damals knapp 1.000 Deutsche Mark. Mit dem eigenen "Anforderungs-Profil" Anno Domini 2018 sollte/könnte/müßte man doch einfach auch mal "die Kirche im Dorf" lassen!

Hi "Karl",

Sorry, but I'm going to keep your post for pure 'intellectual '. In case of doubt, is the European 230-volt power grid and (therefore) additional installed electronics responsible for poorer sound? - I think it is completely free for you to construct something better than that which you criticize!

- Only one sentence of a German philosopher to this, Arthur Schopenhauer: "Any silly boy can step up a beetle. But no professors of the world can make one".

- Or in other words - what just makes me angry - : "If the journeyman wants to explain to the master how to do it right". - Such a thing exists only in internet forums, but never in real life!

Hi Carlos,

Sorry, I didn`t say that the added components in the "(G)" version make the units sound poorer. User Mickey Mouser has long answered my curiosity about the 1991 regulations.

Actually I would like to have a German unit (HK6500 or HK6600) bacause I think it will be much more immune to interferences nowadays.

Best regards.

Carlos: Nevertheless it would seem somewhat impolite to me to switch to German, as the thread starter might not be able to read that (or at least not so easily) and hence might feel somewhat excluded in his own thread.

Anyway, yes, nowadays the trend would also seem to go towards one single model version, because more and more stuff comes with universal (i.e. 100 to 240 V) switched-mode power supplies anyway, so if there already is no need for country/region-specific power-supply variants anymore, one can understand, that the manufacturers would preferably also avoid other country/region-specific variations.

And you might have misunderstood me, because I mainly had extreme examples like the aforementioned Marantz models in mind - whereas the 320 pF of the HK6500 would still seem comparatively harmless. For instance, another such extreme example would be the Teac AG-790, which doesn't only have an excessive input capacitance of 820 pF, but in addition the input impedance is only 22 instead of the usual 47 kOhm. So that's another MM input, which isn't hifi-capable in combination with regular MMs and MIs anymore.

Greetings from Munich!

Manfred / lini

Tag,

and now - the german HiFi-Magazin STEREOPLAY measured the/a Harman Kardon HK 6500 (Nr. 11, November 1989) as follows: "Eingangskapzität (MM) 135 pF".

Freundlich
Albus