I spoke with various people about availability of upgrades for Sansui TU-X1. I have to admit that I have no problems with it sound and my concern is purely intellectual – there are better sounding resistors nowadays and there are better caps then electrolytics in signal path as Sansui used in 70s. So I was wondering what would happen if juts to replace a few parts in the magnificent Sansui TU-X1.

Still, I am afraid that is it will be killed then it will be killed…  and I have see a lot of it in hi-fi… and practically among the Morons who do the parts swapping….

So, I decided to make it clean… I have a second Sansui TU-X1 that I keep for 2 year in my storage – just in case (I too much value my FM experiences). So I decided to bring the second TU-X1 to the specification of my current tuner and then to change the part in signal path to the best contemporary parts. If you read the FM circuit then here is what will be changed:  http://www.goodsoundclub.com/pdf/TU-X1_FM.pdf

1)      R09 120K (or more) -   310K - increase gain

2)      R07, R08, loading 22K   

3)      R17, R18 560R   - 562R

4)      R11, R12, R03, R04, loading 100K  

5)      R01, R02 3.9K (.5W) - 4.1K

6)      C17+C15+C19 combined bipolar and bypassed 10u/16V

7)      C16+C18+C20 combined bipolar and bypassed 10u/16V

8)      C27, C28 1000pF

9)      C602 10uF/25V

10)    C01, C02 0.47uF

Romy the Cat wrote:

The alignment, tuning and changes will be done very soon and then the sound of the both: virgin Sansui TU-X1 and the updated will be compared. I am very interested to hear the result.

What I got the second Sansui TU-X1 I bought it “as new” in Germany and it was sitting in my storage; I did not even open it up what I got it. When I sent it to Connecticut “Stereo Surgeons”, the owner, Ken Bernacky informed me that the tuner is cooked by lighting and absolutely not operational. He rebut the front end of the tuner and then did all necessary further repair and aliments. As the result he suggested that this second tuner should be better (in term of operation, he does not care about the replaced parts) then my first one. Well he tune out to be correct – my “new” Sansui TU-X1 has much better performance. However, this improved performance is not related to the changed coupling caps or better feedback resistors. The new tuner has less noise; better selectively – the characteristic that has no relation to the parts change in output stage.

The first tuner was released by Ken to me with:

Sensitively: 0.8uv
Distortions Wide Stereo: 0.022%
Distortions Wide Mono: 0.015%
Separation: 56dB

This second tuner has the following numbers:

Sensitively: 0.8uv
Distortions Wide Stereo: 0.029%
Distortions Wide Mono: 0.016%
Separation: 58dB

So, the numbers are closed but for whatever reason I have a stronger signal with common stations. As you understand the change of coupling capacitor in output stage from 30 year old polarized electrolytes to the contemporary non- polarized Nichicon Muse has no impact to sensitively of tune  or to its noise. So, I got better tuner but lost the experiment.

Antonio J. wrote:

… In my very flawed and very low resolving system I can feel the tone you're speaking of, which no other of my sources has.

I was playing today a little with my “reminded in service” TU-X1 and what do you know? I found a way to make it to sound even better than before. I mean really really really better.  I mean better up to the point the It I hardly believable. Where I was with it before???

Just in order do not be follow in the damn-glorifications of the “new old” TU-X1 here is a short clip I recorded a few minutes ago. Sorry, it is some kind of crappy local jazz – my local FM stations do not broadcast live any more serious music just according to my demands. Still it dives some idea about the capacity of FM. BTW, the file is 44kHz 20 bit not the 88kHz as I usually do - I did it to keep the file smaller…. You still won’t be able to play it on a regular computer and you would need a dedicated audio machine...

<< File # 1 was here. >>

I had some difficulties to have the file sounding. The software I use to play higher than usual bitrate PCMs (20 or 24/88) on kernel mode to bypass Windows processing won't play the file, then I had to use Jetaudio. It was the only one which worked and played it at 20/44. Perhaps this was the cause, or maybe that I didn't care for the music, but apart from a nice space illusion, I couldn't find the sound any more interesting than the "normal old" TU-X1, in fact quite less right. It sounded kind of dull and didn't like piano and sax timbres. Voice was just acceptable in this setup.
Since this result can very well be for the playback software, I'd be thankful if you could tell me what software could I try that is 20/44 capable and allows to bypass Windows sound "managing" (I'd rather say screwing up).

Rgrds.

Antonio, I disagree. I found it very good result and it is very much irrelevant how piano ir oe what kind timbres the sax has. Come on, this is some kind crappy jazz-band and in a local bar, how much you expect?

The point is that you need to know what you are listen when you are hearing. Did you play attention to HF noise in MET recording? That was from a station that has 80% of signal. The jazz recording wasat 40% of signal. However, look at the nose level at the jazz recording. It is hugely down. The TU-X1 has a circuit of noise redaction hat blending HF between right and left channel, substantially lowering HF nose. Still, if you listed the crappy jazz recording then you will see the HF information is not monophonic but have well defined separation. It means my TU-X1 has now this level of nose without noise redaction.

I do not know what player you use to play those files on your PC but I am very happy with the result.

Romy the Cat wrote:

Antonio, I disagree. I found it very good result and it is very much irrelevant how piano ir oe what kind timbres the sax has. Come on, this is some kind crappy jazz-band and in a local bar, how much you expect? The point is that you need to know what you are listen when you are hearing. Did you play attention to HF noise in MET recording? That was from a station that has 80% of signal. The jazz recording wasat 40% of signal. However, look at the nose level at the jazz recording. It is hugely down. The TU-X1 has a circuit of noise redaction hat blending HF between right and left channel, substantially lowering HF nose. Still, if you listed the crappy jazz recording then you will see the HF information is not monophonic but have well defined separation. It means my TU-X1 has now this level of nose without noise redaction. I do not know what player you use to play those files on your PC but I am very happy with the result. The Cat

I overly impressed with the new way or routing the antenna input with my TU-X1. This tuner with this new input get amassing sensitively (much higher than original) with a nose of a good CD player – very impressive! Way more interesting as it was right after the alignment. A person with whom I spoke, who presumably knows this thing suggested me that now the tuner should be realigned with the new antenna mapping. Perhaps he is right I. My tuner technician who would do the new alignment unfortunately is not cooperative on the subject as he too closed-minded in what he already knows.  Very said. I did tell him what I did with inputs and he is a complete disbelieve, He things that I lie him. I have no idea why people put ego in place where it should be just a curiosity…

Another sad fact. I was trying to get into the subject with the folks from Yahoo FM Tuners Bulletin Board. I have a quite good contacts and people where very useful. The tweak that they proposed to gain more sensitivity of TU-X1 I have tried before and the direct pass from coax to front end that my technician implement worked identical to the Yahoo folk’s suggestion. The FA7 tweak takes the result way beyond it, waaaay beyond. So what was sad?  Well, put the Yahoo FM Bulletin Board in the long list of the only forums from where I was “banned”, at least they believe that they banned me not wise versa. I posted at that forum a few month back in response of a guy to “update” TU-X1 with Black Gate capacitors. I relayed to him that it would be incredibly foolish step. In response my post was deleted and I had a lengthy email form Bob Fitzgerald (one of the Bulletin Board moderators) who informed how I need to reply:

“Instead of telling people what not to buy …. please suggest brands and model numbers of caps that you like, and why.”

I can’t believe that this cretin put himself in position to obligate me what I need to do/say. I suggested him to go go screw himself. Yesterdays I made a number of comments about my new TU-X1 discovery in yahoo site. People reposed and some proposed usefuel ideas why it might be. Suddenly my posts get deleted and I got email from Bob Fitzgerald. This Moron in his power trip said:

“… when I look at anything your emails and posts, they are unreadable, and make no sense.”

Well, probably if for this specific idiot my posts "make no sense" then they deserved to be deleted? Well, I suggested him to die with his fucking secret and this time that idiot got the message – I was successfully “banned”.

Anyhow, behind all of those stupid stories there is truth – the very interning benefit of driving the TU-X1 with “inverted” FA7 input. When I dig to the bottom of this tweak I will post the details explaining how it might be done but for a time being here two images. It is the same station, the same tuner, the same frequency and same position of antenna. The differences are following: The First is driving the front end directly from coax (no balan or anything else - exactly how I got it from my shop). Second is driving the front end from my “tweak” - the “inverted” FA-7 input.