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The Rohde & Schwarz EU-6201 tuner was made for German Ultrakurzwellen (ultra short waves or FM) Broadcast Network. The idea was to have a chain of wide-bandwidth composite signal receivers that feed re-transmitters. I made an attempt to accommodate EU-6201 for my tuner needs. The result is generally positive but not ecstatic. I very much in love what Sansui TU-X1 does and my primary objective were to see if the EU-6201 will be able to compete or exceed the results of the TU-X1.

The Rohde & Schwarz EU-6201 has no MPX decoder on board and outputs wide-bandwidth composite mono signals of the multiplex composite low-passed at 63kHz. After exploring the external MPX decoders I decided to use accommodate one of my Sansui TU-X1 just for stereo decoding functionality.  In the picture below the EU-6201 feeds the Sansui TU-X1 on the right.  The TU-X1 has IM stage disconnected form own the MPX decoder and out stages. The TU-X1s auto-muting circuitry is defeated and stereo engaging circuitry on TU-X1 is made to be active. The Sansui TU-X1 at the top shelf is a “default” TU-X1. Both TU-X1 and EU-6201 + TU-X1 made to output very identical signal level and they drive juts different inputs of Placette active. So to see the different between the tuners is very simple…

A few words about the Rohde & Schwarz EU-6201. It made more then wonderfully. I will not talk about it – take a look yourself:

http://www.goodsoundclub.com/Site_images/Rohde&Schwarz/

Still, it is highly possible that EU-6201 is not made optimum for what I need to get out it. The automated stereo recognition options is not necessary in there for my needs, the very powerful high-gain output stage not necessary for my needs as well, the very sophisticated low-pass filtering options are no good for me as well. So, I ordered the schematics of EU-6201 and I am sure Dima will find a way to optimize the operation for my need. UHF is Dima’s originals trade and he very much knows what and how to do with tuners. Will see where it would lead me…

As the default EU-6201 driven into TU-X1’s stereo decoder/output stage is very comparative to defeat Sansui TU-X1 I turn of sound, in fact the sound of those tow tuners are remarkably identical. This bring to attention the question: when we are not taking about tuner reception but sound quality then do we really talk about juts the sound of the stereo decoders and out stages?

Anyhow, the EU-6201 and TU-X1 have the same decoder/output and they sound the same. There is a VERY small difference in reproduction of the very lowers notes but the difference is very-very small. The difference is so small that it is lower than the difference between two Dominus cables (depends who assembled the cables in POD). Could the difference be neglected?  Hm… I do not know at this point. I think that the difference might be fine-tuned by loading of the EU-6201 out stage. Currently I load the Rohde & Schwarz EU-6201’s wide-bandwidth out (better sounding then filtered) to 900R (10.000R and 1000R voltage deviser before Sansui decoder).  Perhaps lowering it  higher or lower I might altering the minute  satellites of the lower bass but I did not play with it as I ultimately would like do not used the  Rohde & Schwarz’s output stage at all…

Well, if there is no big deference if any deference at all in Sound of the Sansui TU-X1 vs. EU-6201 +TU-X1 but there is quite a large difference in reception. Sansui TU-X1 has its auto-gain circuit before the second stage’s narrow filer and it make the TU-X1 tend for overload in case of a there is another  strong station within the wide scope of the first filer. The Rohde & Schwarz is much more intelligent in this circumstance and it is more immuned to overload. It has better reception for far stations and better noise; still it might derive from the Rohde & Schwarz’s ability to better filter stations.  It hard to say anything without seeing the schematics…

Still, if to use the antenna attenuator and fine-tune the antenna on Sansui TU-X1 for each station (it is what I do anyhow) then the Sansui TU-X1 delivers identical result to EU-6201. Only for very far-located stations or in the conditions of heavy multipath Rohde & Schwarz EU-6201 succeed Sansui. Sansui might resist in this condition if I switch Sansui in “Narrow Mode” but then Sansui loosing its glorious Sound quality.

So, the Rohde & Schwarz EU-6201 is a good tuner. It less convenient to use then Sansui TU-X1 but in its default version it might have some potentials. Let see what Dima would be able to propose to do with it after he overview the EU-6201’s schematics. Theoretically if to get rid from Rohde & Schwarz EU-6201 whatever is not necessary in there and then custom-build inside the Schwarz’s chassis the proven good sounding Sansui’s HA11223W-based PLL multiplex decoder then it might be interesting. The Rohde & Schwarz EU-6201 has two output channels and it has two separate output amplifiers that drive each output separately (!!!). The amps (you can see one of them on the picture):

http://www.goodsoundclub.com/Site_images\Rohde&Schwarz\DSC_3160.JPG

…are made as plug in card in the EU-6201’s motherboard.  The connectors on the card have input signal, access to output signal and power. So , why instead of the high-gains out stage (it dose around 10V in output – I dove with it my entire Macondo) to make a plug-in card that would have a decoder and a good quality 2V output buffer?  Well, let see how it all tune out in future.

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