Romy the Cat wrote:

What kind antenna you use: 300R or 75R? What the Sansui’s antenna jack you use? I presume that your “small car antenna” uses 75R coax cable and your use the75Ohm Sansui’s input?

OK. After a few days of self-education and harassment of various technical people I got what I need – the truth and the reasons why both of my Sansuis TU-X1 sounded so honorable from 75R FM input and so much better from FA-7 input.  Below I will provide the detail expansion. I have to admit that the reason was partially my ignorance but the result of the journey to figure out the mechanics of my improvement was very educational.

Oh, but the way, the readers of my site like to laugh– the indomitable abovementioned Baba Fitzgerald issured to me Cease and Desist ultimatum:

“... If you don't remove my name and private email content from your site forum I will do something about it .... I will contact your ISP, and complain. You may hear from my lawyer for libel, and threatening obscenities. I will also complain to the City of Cambridge, where I have friends on the Police force and in government. Your address and location are known to me. “

Great! He can stop by in my parking lot and fart into all 4 tires on my ugly BMW! What a Moron!

Anyhow, I had a conversation with my technician Ken Bernacky from Stereo Surgeon who calibrated and aligned both of my Sansuis. He for whatever reasons was defensible and felt that I was complaining. Complaining was never my intention, I just wanted to get the rational of this thing. I had no doubts that Ken pushed out on my TU-X1 whatever best was necessary and possible. However, what I heard was also self-evident that FA-7 input with 300R coax connect to front end was incontestably better from point of noise and sensitivity

Ken Bernacky commented on it:

“As you received the item back from Stereo Surgeons FA-7 was not in the circuit, the front end was wired directly to the 75 ohm FM f connector input.  Any signal that you were receiving from an FA-7 input was due to stray capacitance and would be greatly attenuated rendering the tuner useless for anything but extremely strong rf levels.

You indicated to me over the telephone that you have opened the item and reconnected the FA-7 coax plug to the front end of the tuner.  Reconnecting this provides you an attenuated signal with reference to the sensitivity achieved by my bypassing FA-7.  The attenuated signal is due to the increased losses of the crude FA-7 switch which is actuated by a side push in rod found on the side of the FA-7 f connector and additional components.  You making this change would only mildly affect the input tuning of the very first tuned circuit in the front end and does not affect any tuning adjustments past the very first tuned circuit in the front end.  What you have accomplished is to lower the sensitivity of the tuner.  This is not desirable, the desirable way to accomplish the same result is by feeding a signal of lessor amplitude from your antenna thru the 75 ohm f connector.”

I very much not in position to argue with Ken but I accustom to consider that what I hear is what it is. I looked at scope the output of my antenna coax with 60% signal strength on Sansui’s meter:  it was .200mV. The output of my FA-7 input was order of magnitude lower, much much lover. It looks like Ken was correct and my signal flood the Sansui input and therefore crate excessive noise. Then why both of my Sansuis have much better sensitivite driver from FA-7 at very weak signals? There was no explanation.

Well, after consulting with a few guys who did not give me a satisfaction I desired to put the heavy artillery into the game – I called Dima.  UHF is Dima’s specialty and he looking at the Sansui TU-X1 circuit gave the prefect explanation of what happens with my TU-X1.  Dima explain to me that the problem with my tuner was.... my bad technician who juts made to me too sensitive tuner. With the strength of my antenna (the one that Ken incentivized me to install and use), with the sensitively of this tuner and with amount and of the FM stations in Boston Dima proposed that Ken should release this tuner accompany with 40dB coax attenuator as overlay strong signal toss the Sansui’s front end into distortions that produces extra noise. I went and bought the 12dB, 23db, 27db, 33dB, 45dB attenuators and they worked absolutely perfect with regular a high sensitivity FM direct=pass input. In fact playing with attenuators, I concluded that my aligned Sansui has it's best relationship between sound and noise when antenna supplys only 40-45% of signal strength on my TU-X1’s meter. Dima explained that in the TU-X1 the metering is done “properly” and the signal chain and meter chains are completely separated and not even connected. He proposed that the meter chain might be recalibrated for the new sensitivity, but I do not think I need it. I just learns that in both of my TU-X1s,, after the Ken Bernacky’s alignment the 50% of the signal strength become my new max limit over which I should not go, or I pay the price of noise.

Now, if it is so then why with signal attenuation after the FA-7 I had better reception for far-located stations? Dima explained that it has to do with the TU-X1 design. The TU-X1 has (I am paraphrasing) first relatively wide bandwidth first filter and then a second stage/filter that runs automated gain control. (I do not use the TU-X1’s “narrow” setting – bad for sound). So if in the bandwidth of the first filter there is a week signal and a part of strong signal then the second narrower filter's automated gain control adjusts of volume for the week signal, which is overloaded by for the strong signal. He explained in details why lowering the signal strength and this particular tuner should help in this satiation but it is beyond my ability to repeat. What is important that it is works no mater how not initiative it is – with sticking 12dB-23db attenuator on my antenna I “see” more stations in noise and get them much cleaner. I think Ken should release his tuner with some kind of “sensitively warning labels”…

I know, it is kind of contra-intuitive to kill output of antenna to get better sound. But I learned that I need to do it. How about the Sound difference between the FA-7 input (that do attenuation) and the FM input behind a right coax attenuator that would set the signal level of 40-45% on the TU-X1’s meter? The FM input unquestionably better: it has better bass, way better “space” and much, much, much more sophisticated imaging… and the SAME noise level.

So, my “FA-7 alert” was false but it was very enlightening for me to get to the bottom of those thighs. Thanks Ken, thank Dima and ….thanks the TU-X1.

Antonio J. wrote :

"...I'm using an indoor antenna which in fact is a small car antenna, placed besides a window. The good part is that I can move the antenna and get the orientation that yields stronger signal. I'm living in an 11th floor in a building of 13, I don't have a balcony and the community wouldn't allow me to put a ddicated antenna on the roof, nor the building's outer wall. I get the active from the car antenna to feed the center of the coaxial wire and this carries the signal into the coax antenna input in the receiver. With this very challenged system I manage to get good stations at about 80 to 90% of signal, but still there's some noise. Good days it's pretty quiet, but others is terrible and I rather listen in mono..."

Back when I lived on the 17th & 18th floors of a highrise (the case up until just three weeks ago) I had the same problem. To make matters worse, "my" high-rise was surounded by other such tall buildings. I solved the problem by using a Godar Model 1 indoor antenna (used in my case with a modified Sansui TU9900). You might want try such an antenna. They are not expensive, industructable and very light-weight, so should be no trouble to ship form the US.

The Model 1 was particular in that it had in addition to a periodic log array antenna, a couple of telescopic rods that could be aimed in the direction of the transmitting tower, or lined up to make a long dipole. Such a model is no longer available; the Model 1 has been replaced by the Model 2A; I can't speak for the performance of the new model, but I doubt that Mr. Godar would replace the Model 1 with a design that did not perform as well or better... In any case, he does answer emails and telephone calls...

Above I made comments that despite my new Experimental Sansui TU-X1 with better parts is much better (I have someone who actually objectively measure it)  but the old and not modified Sansui TU-X1 has that advantage of the unique tone that I values very high and certainly do not want to lose.  It is not that the Experimental Sansui TU-X1 sounds like McIntosh - it still has all TU-X1’s thing s, but that glorious vocal infliction of the “old black man from Mississippi” is slightly less in the Experimental TU-X1.

I was blaming the better and cleaner parts that I put in the Experimental TU-X1 (and they are much better and much more transparent parts) but there is catch in that thinking – I did not listen my Experimental TU-X1 BEFORE the parts were changed. Bothe tuners are 30 years old and it is very possible that they just aged differently. The Experimental TU-X1 spent it’s 30 years in Germany and my old TU-X1 lived in Vermont for it last 10 years. Only god knows what they did and how they were used. However, Ken the Technician proposed that the difference in them might be even before we started to work with parts modification. Well, it does make sense and might be a possibility. Of course no one would say defiantly at this point what is what….

Romy wrote :

"...I know, it is kind of contra-intuitive to kill output of antenna to get better sound. But I learned that I need to do it... BTW, if anyone knows where the source a 75Ohm 0-40dB (not 20dB) LPAD with coax input and output cables going in and out from the BACK of the unit then please let me know..."

It looks like this issue was taken into consideration in the design of the Sansui TU990. I use a modified version of this tuner. The TU9900 has an antenna attenuator button on the front panel (not the result of a modification; it was sold new with this feature)... I am not really sure if this leads to "quality attenuation" or not, but with some super strong signals it does sometimes improve sound; in which case I don't hesitate to use it. Looking at the photos of the TU-X1, I am surprised to not find such a feature.

I live where FM program quality justifies a good tuner. Despite getting what I consider to be really excellent sound from this modded TU9900, I will one day compare it to a TU-X1. I will post my findings here.

jd*

jessie.dazzle wrote:

I live where FM program quality justifies a good tuner. Despite getting what I consider to be really excellent sound from this modded TU9900, I will one day compare it to a TU-X1. I will post my findings here.

Jessie, if you live in a place with good FM program then with a good tuner it completely redefines what high-end all about…. I never heard the TU9900 and it you lay you hams on TU-X1 it would be very interesting to learn how they compare.  BTW, here in US we have no interesting AM programming (just new and talk show) but in Europe, where everything is much closer you might have better AM programs. The TU-X1 has remarkably good AM sound – I was very surprised how far it is from what we get in car. BTW, according to Dima the TU-X1’s AM section is much more sophisticated and according to him “proper” then the TU-X1’s FM section

glaesemann wrote:

The lightning strike may have caused changes beyond the obvious damage as well. I knew a caddy who was hit by lightning and though it didn't kill him, he was never the same again either.

Perhaps it is what I was asking Ken many times. He assured me that whatever damage was done by lightning is completely rectified and there is no memory in the tuner that it ever took place.  Tell it to your caddy… :-)

Romy wrote:

After a few days of self-education and harassment of various technical people I got what I need... – the truth and the reasons why ….

Regarding the overload – here are the fragments of valuable  comments of “John A” who helped me to learn more about the problem:

“ Overload is a bitch with most of the high sensitvity vintage tuners! …

The TU-X1 meter should be calibrated in DBf and thus if aligned properly should work fine with ONE 100dbF signal.

But when you throw 2 or 3 very strong signals close together at it, then it just pukes!. I don't have overload here with my modern tuners but my vintage units will  get "hissy" when my antenna aims close to a local around 100dbF here. Keep in mind that hiss is not the only symptom of overload as some of my tuners increase sound "hard" or strident as the signal becomes too strong. 

The Kenwood L-o2T which has RF and IF AGC should work for your conditions better, but a Technics 9030 is probably best for handling overload, unfortunately it doesn't sound too great without major modds

It is inherent in the design, as it has 2 RF amps when almost all others have only one. It was designed to be a supertuner spec wise so Sansui went nuts on the RF gain to get the best "marketing" numbers (8.7dBf) where people would recognize the superiority vs their other tuners and the competitions. The high end Kenwoods and Technics used less RF gain and balanced mixers to avoid overload but had nowhere near the sensitivity as a result. There are always tradeoffs and tuner RF dynamic range was not as big a concern then as it is now.

Tandberg with their TPT3001a repeated this "tradeoff" of extreme sensitvity at the cost of overload resistance. It has around 8dBf usable sensitivity too and overloads like crazy also. In todays FM environment you would need to live way out in the boonies to use this level of sensitivity.

More recent tuners even bypass the RF amp completely in LOCAL mode (best solution) or have PIN diode variable attenuation to kill excess signal. In your current location it would have been best if Sansui had bypassed the 1st RF amp with a local mode switch. No gain = no IM distortion

Going from 5uV to .8uV is about 16dB more sensitive,so why do you need >20dB attenuation if you didn't have overload hiss before the alignment?

Going higher than 20dB attenuation may be questionable becuase you will throw away much of the quieting that the TU-X1 is capable of .If you look at the curves on the broachure you will see that your tuner doesnt get to max S/N until 70 to 80dBf, so if you have to attenuate all the way down to 50dBf you're not even close. If you are having problems with a very strong close station you don't want to listen to, a notch filter may be better.

This issue will be a problem for your more distant stations not the ones less than a mile from you. The nearby stations (within 2MHz and location) will cause frontend distortion while the distant station will be weak. Your experimentation with attenuation and antenna aiming will have to determine the best compromise. You'll have to minimize hiss and multipath for two input variables. Lots of fun tweaking!”

I need to address sometime this problem as many of my recordings are in random channels order. I have one of my local stations that have very good programming being very negligent to the correctness of the right and left channels and very negligent to the accuracy of signal. I sometimes flip the channels to chance what they do and sometimes I do not do it as I schedule recordings. That all crated a situation that I stopped to care what is right position of the channels on my recording systems. What I load a file and play it is very simple to flip the channels in WaveLab. I think I need to set all my recording dear to the right R/L setting and keep it this way, juts resaving the wrong broadcasted files in reversed configuration. I know that inversion of file do not activate any DSP or anything like this but still I treat the original file as tape masters and tend do not screw with them.   It would be nice to have channels reverse on DAC via a remote control…

BTW, tonight we have live-to-tape Mahler 4 and Das Lied von der Erde from Concertgebouw lead by Bernard Haitink. Two days later we have live-to-tape Keuris: To Brooklyn Bridge, Dvorak: No. 9 and Schat: Arch music for St. Louis by Netherlands Radio Philharmonic orchestra with Edo de Waart conducting.  At the same day we have LIVE broadcast Jennifer Koh play Bach. On Sunday we have Donizetti “L'elisir d'amore” LIVE broadcast from Shubert Theatre… + LIVE MET on Saturday…. I did not mention the rest of FM programs.  Who the hell needs those CD/LP/Tapes and the rest crap with such FM programming?

Juts cough 2 hours ago a “live” broadcast of the air with Violinist Jennifer Koh plays Bach partitas.

http://jenniferkoh.com/

I think it is enough to hear it to get what I mean about the worth of FM.

You have to be able to play 88/24 format and the 64-bit files to listen this recording. (If you do not do the 64-bit then try to rename it into WAV)

<< File # 1 was here. >>

Wow Romy, I wish my local stations broadcasted with that quality and I managed to get them with that ultralow noise floor. Really wonderful music and sound quality (in the context of my handicapped computer system).

Were you up to the task to upload or sending (maybe a DVD-R with the raw files) some really worth performances, just let me know. I'd happily pay any expenses. I know I'll never be able to enjoy them with the same "audio quality" as you do, but I really don't care, it's the nice music they program on your FM stations what I find wonderful. I have several versions of the Bach's Partitas, I don't know if it's the FM or that they caught Ms Koh in an illuminated moment, but none of the versions I know has that nice balance of Bach's brains and player's emotions. Really beautiful. Thanks for sharing Romy.

Rgrds.

I scheduled today to record the BSO’s Friday broadcast and when I got home I have a good surprise – it was not bad.  Garrick Ohlsson played Schumann Piano Concerto with BSO lead by Daniele Gatti . The BSO was “here and there” most of the time but in the very end they warmed up and it was better. I like Garrick Ohlsson, he is frequent in Boston and in the end it was a good Schumann Concerto.

BTW, it is ridicules why the file, if I take a fragment out of it, is losing quality and picks some alien noises and pitches (!!!) aberrations.  You can head in the beginning there are some strange mechanical sounds that I do not have in raw file. Anyhow, even “as is” it is good enough. Live performance is always live. The file is as usual 88/24

http://www.badongo.com/file/8285819

The Cat

Hm, I did not know that they spited the file on two halfs. I presume that it was their “catch”. Immediately uninstall the software they made you to download and run the intrusion detection procedures on your PC.

The Sound you heard on Schumann Concerto has nothing to do with recording – it was how Daniele Gatti made the BSO to sound. He made BSO to sound in a way sharp, shallow, with underdeveloped bottom, with bad use of the Hall, with overly prominent cupper group - very uncomfortable sound. They played after Schumann the Shostakovich Fifth and it was nightmare. The opining of the Fifth’s last movement sounded nothing short then Khachaturian’s “Saber Dance”…

Today there was a broadcast of Gaetano Donizetti “L'elisir d'amore” from our local Shubert Theater by Boston Lyric. I always love those small-stage production – they might not have the killing cast but they try honestly and have that boutique quality…

http://www.blo.org/season_elisir.html

The Theater is small 1600 seats, with orchestra in a pit and the entire theater has small but very hommy sound. The “L'elisir d'amore” was very nice today: friendly and kind. Here is a fragment from the beginning of the second act…

http://www.mediafire.com/?lxyj4yyj3ly

I still disappointed that it is imposable to “save file as” without loosing Sound quality – my ordinal file is WAY better. Apparently by “save file as” the stupid WaveLab activates the re-rendering even if the rate and resolution was not changed.

I brought home another "top-rating" tuner with better front-end and trying to see if the TU-X1 hold the ground. The competition was groundless – Sansui destroyed the contestant, I will talk about it more in future.

Minwhile it was a broadcast today that was virtually meant to demonstrate the TU-X1 virtues. It was Richard Hickox leading Leipzig Gewandhaus Orchestra with Christian Giger, playing Britten Symphony for Cello. Unfortunately I can’t not to let you to listen the file at full 88/24 as it become too large and the file sharing service that I use has 100Meg limit for a single file. So, I down-converted it 44.1K and 20Bit, the file is 75Meg.  Of course the quality went down the hill but still you will have the idea.

http://www.mediafire.com/?wwmcedb20j2

The FM broadcasts is where the truly high end lives.

Dear Antonio,

RE: your question about what the FA-7 connector is for, the TU-X1 brochure says:

An "F" type connector is provided exclusively for use with the optional Sansui FA-7.

...

FA-7 FM/AM Compatible Antenna System:

- World's first FM/AM compatible antenna system (Pat. Pend.)
- Both FM and AM reception is possible with one antenna and one cable connected to receiver/tuner's FM/AM terminal
- FM antenna with sharp directionality for reduced multipath interference
- non-directional AM antenna.

RE: connections that are being used on my TU-X1:

- FM antenna to 75 ohm cable to ANTENNA FM 75 ohm (unbalanced).
- AM antenna to ANTENNA AM and ANTENNA GND connectors.

- FM OUTPUT (FIXED) (L & R) to my amplifier (L & R inputs # 4).
- OUTPUT-1 (VARIABLE) (L & R) to my amplifier (L & R inputs # 5).
- OUTPUT-2 (VARIABLE) (L & R) to my amplifier (L & R inputs # 6).

We reside 50 miles from the closest broadcast towers and the FM station that I am usually tuned to reads about 82 on the dBf FM Signal/Multipath meter.  The FM antenna uses 2 FM antennae mounted parallel on a pole with rotator and remote controller.  The AM antenna is a heavy duty remote tuned AM loop antenna with control box.

Regards, Peter Foster.