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Serious Manufacturing by American, while the U.S.A. has not been so serious about.

It was January 1991 when I encountered this magnificent Tube Power Amplifier at a show booth for High Quality Audio Equipment at Winter CES in Las Vegas. I am kind of surprise-hard on most of things through my life after having experiences on a lot of things and playing with them. I, however, was shocked by this Monster or shall I say Giant like THE800 and at the same time I got an emotional feeling, I was about to forget, that is 'if American designs and manufacturers products at very serious heart, we Japanese, can never beat it'.

We lost at World War II I am not post war generation and I know how we got through poor material world after the war. On the contrary, during the period of time, U.S.A. had been very powerful and with full of rich materials. U.S. kept manufacturing all kind of products, hanging Out like a Dogwood Sandwich's, by herself. These products shown on that big Sears Catalog brilliantly caught my eyes while I was very young. That U.S. looks like forgetting to produce the things in these days. We, of course, can not simply say “deteriorated like Rome“. But also it is obvious that U.S. is manufacturing very few thing. If you go shopping to department store or mall, very few Made in U.S.A. products are available for home appliances, or items for day to day life. These are coming from Red China, South East Asian Countries, Nepal, or Jamaica where the manufacturing cost is low. And of course a lot of Made in Japan products. In other words, it is very difficult for us to find out Made in U.S.A. products in America. When I shop around in U.S., I always try to buy Made in U.S.A. stuff but there are very few chance for me to buy such now. Whenever I can not buy American Made product, my memories in childhood does not fit well together with the America who does not produce many products any longer.

But THE800 reminds me once again for sure that America designs and manufacturers magnificent stuff when American is dead serious to do so. THE800 is superb and unbelievably great and I feel some kind of fear to come close to it.

Official type number of THE800 is GTR-800. GTR stands for Golden Triode Reference. THE800 is nick name of GTR-800. Easiest way for us to know the details of THE800 is to actually, touch it. I believe that every one is to be shocked knowing the details though. Let's begin.

THE800 is all tube type mono block power amplifier. Amplifier section is totally separated from power supply section. Therefore it is consisting of 4 chassis for stereo pair unit configuration.

Chassis dimension is same for Amplifier and Power Supply Unit, like, 47.5(W) x 30(H) x 93.8(D). Therefore, size of stereo pair configuration is larger than one Tatami mat. The weight is 77Kgs for Amplifier and 93Kgs for Power Supply Unit, Again for stereo Pair, the weight is Super Heavy of 340Kgs and this is heavier than Japanese Sumo Wrestler, Ozeki Konishiki. You are too early to surprise. Its power consumption.
For stereo, if you turn on the power, it sucks up 1800W at maximum output power, you need 4600W, i.e., the current drain is 18A at stand by, 46A for max. output power.

Normal contracted current drain usage limit for standard Japanese household is more or less 30A and the left over is 12A while it is standing by at no signal. You do not want to use it with other appliances. Max. power easily blow off your power breaker.

220V of AC version can be selected when you purchase it and it is recommended in accordance with our safety regulation.

The above is the Outline of THE800. Dimension, weight, and power consumption, every one of these specification, tells us that it is super power amplifier represents the seriousness at the end of the century, sticking with the device such as tube.

Obviously, reader of this magazine would like to know the price of THE800 in domestic market. It is not yet decided but it should be going over Yen 10,000,000.

What? Yen 10,000,000, You can buy a neat car!

THE800 does not fit along with the person who may come up with above comments or who has similar sense of value. So as the sister model THE400.

THE400 can be said like a half size model of THE800. It is same like a mono block but the Amplifier and Power Supply are in one housing. Out power stage is 5pcs of KT-99 parallel push pull/or 1/2 output power which the price would never be 1/2 of THE800 though.

Output tube, KT-99, may not be popular to whom has relatively good knowledge about tubes. Let's explain about KT-99 briefly. KT-99 is 5 pole beam tube and socket is 8 piece connection is same as KT-88. KT-99 has 15% better performance than the KT-88 and almost same specification for KT90. EI of Yugoslavia have started manufacturing 1990 and therefore these tubes are very new.

Tube Research has selected KT-99 for their product development and VTL has selected KT-90. KT-99 has same specification as KT-99 but its construction is rather durable than KT-90.

Amplifier section is consisting of 10 x KT-99 parallel push-pull, total, 20 tubes. Phase shift circuit and 1st stage are designed by using 6SN7. Output power is 800W for Triode model and 1,600W for Pentad, UL connecting mode model. One of these 2 mode models should be selected by purchaser. Small semi-fixed resistor is installed at near by each socket of TK-99 which can control bias current by using dedicated switch and meter. Input line is only one through RCA terminal which does not have input controlling device, but, muting switch only.

Out put terminal is banana plug compatible gold plating big terminal of 2 ohm 4 ohm/8 ohm. Characteristic feature is NFB switch which can select 0dB, 2clB and 6dB. Needless to say, 20pcs of KT-99, huge output transformer, and super
big Amphenol connector are never seen on the other models and these give the unit magnificent image.

2 of these triodal core transfer are used, one exclusively for heater and other for high voltage in power supply section. All the power sources are coming from it. High voltage of 575V to be supplied as plate voltage of KT-99 after regulated by voltage regulator circuit consisting of many of these 6AS7 and other regulating tubes. High voltage of 535V to be used for screen grid after regulated by 6AS7 x 1 pcs plus regulating tubes. 335V is regulated by 6EM7 and regulating tubes. Negative voltage circuit is also regulated by regulating tubes. To short, all power sources except heater power are regulated by such circuits and not mentioning in details here but these are filtered by super big filter capacitors. There are power on/off switch (also to be used as breaker looks like) and 2 of these big Amphenol connectors and IEC spec. power supply terminal. The reason why I describe it as power supply terminal is that no power cable comes with the unit. I have never seen the amplifier without power supply cable.

I am really surprised to see this but you have to make one by yourselves because of very high power consumption or use Cardas cable recommended by Tube Research. Also this gives user a flexibility for choice of cables or its length. All above for the power supply unit is to contribute for the solid performance of the amplifier section and all tube design of the power source is, probably, because Tube Research does not want the noise (including high frequency noise) when the semiconductors are used in the power supply section.

At any rate, I shall amaze, their seriousness of using, non-contacting device, tubes in Amplifier and Power supply, the extraordinary concept.

I am listening triode type THE800 in my home. It seems TRE800 uses good output transformer. There is no typical muffled sound of output transformer. Because of
10 parallel push pull circuit is used, internal impedance is much lower than the one of normal push pull. I would say about 300 ohm. Turning ratio of output transformer is rather easier than the normal one, and therefore less muffling effect from the transformer.

Sound from the amplifier is very pure and quickly responding which some time forces me to forget the magnificent of the THE800. The image of pureness. If the power amplifiers use transistor can reproduce this sound, I would not pay much attention to tubes but I do not know when such thing can be in the reality.

For the time being, I would like to distinguish the one from the sound depending
on rationality or economical reason as I feel that it is not the best thing for me to
be deep in the sound of transistor producing. THE800 tells me that very straightforward.


I turned off air conditioning now. I do not need to heat this audio room. The heat from 6AS7 which are used for regulating circuit is tremendous. I may not be able to get good air conditioning in summer time. (Older amps used 6AS7 tubes which run hot. Now we useKT-90 for power supplies.) ..

Now, I am very much interested in knowing about how many people are going to use
the THE800 in Japan. As long as the tubes can be supplied continuously, THE800 can be
with you for all of your life. Wondering how many people in Japan are going to look
for romanticism on audio sound. Only 7 of those THE800 with magnificence at the end
of century are existing in whole world (as of 1992). 2 in America, 2 in Sweden and 2 in Hong Kong and 1 in Japan.

If extraordinary is the world for real audio hobby, THE800 as a power amplifier
is very close to it. And at the same time, all I can say is "that is romance" when I see
the serious approach in THE800 toward the tubes as non-contacting devices.


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