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07-28-2008 Post mapped to one branch of Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 1
Post ID: 7926
Reply to: 7926
A tube tuner? REL Precedent 646C

A couple months back I sent to Dima a link with a wonderful collection of audio articles from first part of the 20s century:

http://www.one-electron.com/Misc_Docs.html

In next couple days, talking with Dima he asked me: “Roma, what is REL Company all about?” I told that REL is a British company that makes subwoofers? “How good their tuners” Dima asked. I answered that I have no idea – “Most likely if should be nothing special if they do any”. Dima replied that it is very strange as at the link I sent his he came across a schematic of R.E.L. Precedent 646C FM tuner  (closer to the bottom) that was one of the very few schematics that he feel was describes a near perfect tuner. Dima, did pointed out to some simplifications as shortcoming of the schematic but he also told the it was the most properly made commercial circuit he even seen. Dima, pointed out: “This REL was designed by people who truly knew what they do and from point of tuners design it is almost as good as Rohde & Schwarz EU-6201 but made around tubes. Roma, juts because the tubes the REL might be even better then the Schwarz. Get it and try it.”

http://www.goodsoundclub.com/PDF/REL_Precedent_646c.pdf

Well, I have some aversion to tube tuners:

 http://www.GoodSoundClub.com/TreeItem.aspx?PostID=7892

Never was able to have them to sound right.  They have fine reception but no good sound to my ears. However, considering the in REL tuner there is not sound before output of detector and considering that I was not going to use anything after detectors I decided to try. I learned the REL stand from Radio Engendering Laboratory of Long Island NY. The company is long gone and the Precedent 646C was their flagman model. There was some chatter on line about REL Precedent but what I was able to read more indicated about the Moronity or Idiocy of the people who pass their comments then about providing any useful information about this tuner. Not to mention that I generally treat the comments of audio people about audio with no more esteem then blabbering of a 3-year old baddy about the Theory of special relativity.

Recently, I discover 4 REL tuners available for sale and I discovered that one of them was serviced and aligned by Charles King. I dealt with Charles around my Stellavox machine and was very pleased with his service, he is also one of the few who hears and recognized the heard. So, I decided to give it a try… I even drove 100 mile away as the tuner never was shipped after the Charles’ alignment – I would like to keep it this way…

REL_Precedent_646c.jpg

The very first thing that I did was checking how different Morons told me that Precedent is “spectacular” mono tuner and that “it is so good in mono that you would not need stereo”.  Well, I was listening the Precedent in full mono. I was revolting. The tuner has fine reception, not super-sensitive but fine selectivity and low noise. However, the quality of the sound was not just revolting but truly laughable. The Sansui TU-1X goes 10 times better running AM of the stock antenna...

Then I disconnect the de-emphasis network from REL and run the composite signal to my external Multiplex decoder. It was also very bad. There was not good bass and not good tops. The sound was euphoric, lazy and truly tube-like in turns of very-very bad tubes design. Dynamic is not there and my system sounded more like 64dB sensitive electrostats driven by a 2A3 amp… It was clear that the REL’s output stage is garbage, what is very much visible and was predictable from the schematic. Taking the signal before the REL’s output stage, right after the detector changed situation a LOT. The sounds become listenable. It is still not as good as Sansui of the Schwarz. It is not even contestable at this point but I think it is a good first step. I would n to put a buffer after the REL detector to drive my multiple and make some minor change in the REL detector (change diodes to Shotky and the 2 mixing resistors to better resistor). I do not know if the REL will be able to sound at the level of TU-1X or Schwarz. I hope… From the positive side: REL it looks like has some elegance and grace. It has no balls, perhaps the week detector can’s drive my 1.5 meter cable to decoder. Charles is putting the MPX decoder right into the REL – but I did not hear the complete unit with a built in decoder. It does not make send for me to put decoder into the REL as then it would force me to use another decoder in Schwarz and to replaces the cables if I would like to record the FM feed (I have just two A/D processors).

So, so far the REL Precedent is very much NOT plug and play solution and it would take some efforts to make it sound good – of it ever can sound good. Now is a bigger question: what the hell I am trying to accomplish and why I am being a fool with 3 tuners. I admit that I do not need 3 tuners. I need one or max two that would be optimized for the specific reception condition (strong local vs. weak suburban from saturated local). With all equal I would stay with TU-1X with pain in ass manual attenuator. I do it for sake of sound – the untouchable, particularly this specific unit that I left for myself. The TU-1X  is also is extremely comfortable to use. I also stay with Rohde & Schwarz EU-6201 as the best SS tuner ever built. Schwarz kills TU-1X in reception and equal to TU-1X in sound BUT I still would like to have Schwarz with better decoder and be able to over-perform TU-1X. So, what REL doe in my room? The RELL is trying to do what TU-1X or Schwarz do or perhaps is trying to be better then they. The stupid debate about tube vs. SS is being played with my tuners again only now we do know that fro Radio Frequencies the tubes are questionably better. If REL is the most promising tube tuner ever made then now I need to learn how to get out if it a adequate sound. Will see what happen next…

Rgs, Romy the caT


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
07-29-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 2
Post ID: 7936
Reply to: 7926
The detectors diodes in REL tuner.

One of the ways to drag the REL tuner in the realm of civilized sound is to get rid of any crap that it has after its detector. One of the first things is to replace the 60 years old Germanium diodes with contemporary ultra fast and ultra low capacitance Schottky detector diodes. However, it is a quandary that I have: why do not use the tube detector diodes? There were those sub-miniature vacuum tube diode that might do fine:

http://home.netcom.com/~compactron/tubes/5647.pdf

I took the REL’s output amps and the follower out and I have two filaments available to drive the tube detectors… So, another little battle of tube vs. SS, only now in the realm of detector diodes. The good part is the REL is made with extremely easy and very comfortable access to anything and to try different detectors is a matter of a few minutes. A pair of new detector diodes, a par of new RN60 resistor after the detector, perhaps a pair of 47pF mica caps to ground and the output buffer for composite signal – it is all that I am willing and able to do with this tuner to make it to sound better. It might be interesting to see how it goes…


REL_Detector.JPG

Rgs, The caT


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
07-29-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 3
Post ID: 7942
Reply to: 7936
Tuna Fever (Full of Caps)
Romy, this is quite interesting; supposedly, the Marantz 10B was a knock-off of this, if I recall the lore correctly.

Of course you will give this Grande Dame ('54 - '55 ?) a fair shot with some new parts, apropos?  Especially new caps?

I have outsourced some electronic work to a local tuner guy, Mike Zuccaro, who used to (and may still) own one of these that he used with outboard MPX/stereo, and according to him it works well.  I have not heard it enough to comment, but I admit I liked a couple of hot-rodded 10Bs I have heard.

Maybe even the output stage would be OK with new parts?

Best regards,
Paul S
07-29-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 4
Post ID: 7943
Reply to: 7942
I do not touch the RF. Absolutely not.

 Paul S wrote:
Of course you will give this Grande Dame ('54 - '55 ?) a fair shot with some new parts, apropos?  Especially new caps?

I would certainly would be very interested if someone with RF knowledge would rebuild the REL circuit from scratch, using better contemporary part and better building methods, perhaps with some minor improvement of the REL’s ideas; however I will not be the person who will touch anything in the REL as it is now. I trashed the REL output stage. Whatever in there before the detector diodes is not sound but radio frequency and I have absolutely no knowledge how the RF parts are responsible for sound. There are explanations how the RF solutions effect reception characteristics but not sound, at least it not know to me.

All that I intend to do if to put better contemporary end of the detector and build-in a good op-amp buffer for MPX signal to drive my external stereo decoder. It might be an elegant idea to use the sockets for tubes V14 and V15 to build my own output stage but I never was able to make a transparent enough tube buffer.  If you still deal with Mike Zuccaro then ask him what buffer he used, unless he built into the REL a very sensitive decoder chip.

BTW, I changed today the detector diodes to regular 4pF silicone and the mixing resistors and the sound did got better, much less cotton-like. I weigh when the Schottkyes and the ap-amps arrive…

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-01-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 5
Post ID: 7958
Reply to: 7936
A small step and the giant leap.

A few days back I got rid of the 60-year old Germanium glass diodes in the REL detector and put in there the regular 1N4148 4pF low-signal diodes/ it was quite positive improvement. I need to be said that detector diodes are not the regulars diodes but a core of the tuner detector something that figuratively “converts” auditable frequencies from radio frequencies. So, it is much more than a pair of the diodes but they are THE diodes on the FM discriminators. Yesterdays, I received the special Schottky Diodes that were made for this application. It is 1N5711 diodes - low capacitance, low switching voltage and ultrafast. They were made specifically for use in the UHF/VHF and video detectors, frequency discriminators and wave shaping devises.

Since I am not a huge fan of all that “vintage paranoia” I decided right along with putting the right detecting diodes to redo the whole after-detector section.  Got rid the 600V after-detector shunting caps, putting in their small 100V/47pF silver mica. I got ring the super critical mixing resistors. The where dust-made and literally they dilapidated in my hands when I touched them.  I also, followed the Dima’s Instructions separated the End of the Detector Radio Frequencies ground with Audio Frequencies ground. The signal meter was also removed from output and decupled with own buffer.  All together it is not a huge revision worth $10.

Oh, boy what a result!!!! Dima, suggested the special detector Schottky shell be better but why would think that it would be like this? The cotton-like mumbling of the tuner is gone. The idiotic “vintage” upperbass is gone. The whole upper range is cleared up very significantly with an additional adding a lot of HF extortion. Dynamically it got much more enthusiastic with very nice “crisp” sound, in fact very pleasant sound. Else, believe me or not but the detector with new Schottky outs 6-8dB more voltage then with 60-year old Germanium glass diodes – only this worth the price of addition!

So, what my REL is now all about? It is actually a nice sounding tuner now, moderately sensitive and moderately selective. It is not as super selective as Rohde & Schwarz and it is not as insultingly sensitive as Sansui. It however handles the overload very nicely (I do not use a lot of REL’s signal attention and I have my own external attention).  The Schwarz still have much more sophistication to handle overload, despite the REL’s vacuum tube advantage.  Sonically REL is so far slightly on soft side. It has a genital touch to sound – but it might be my mental pretendectomy to the tube’s nature of REL. With all new HF and dynamic breakthrough REL still is losing to TU-1X in dynamic and slightly in HF. Not as laughably as it was initially but still auditable. The FH are “almost” there but the dynamic has quite a room for improvement. The lower region of the REL probably is the worst. It has no tubby bass anymore, but better REL bass juts made too visible how much TU-1X is deeper and more interning in lower region. I also have some problem with my T85 Multiplex Decoder to read the REL composite signal.  The T85’s decoder read Schwarz’s signal perfectly but it is finicky REL’s signal. I did not figure out yet hat is going on.

Anything is on a positive side? REL has a different type of background noise. I would not say that it is better but different – particularly when a station has own noise and the tuner own notice talks with the station’s noise.

There are few other things that I consider to do with REL. Buffer the output in order do not let the detector to drive the multiplex.  Change the 8 limiters Germanium glass diodes with the Schottky but I need to discover if it screws up the alignment of the tuner. I need to get an Equivalent Series Resistance Meter and to check out those 60-year old caps. Perhaps they are dead and replacing them would fine the bass. There are a few other minor things…  Anyhow, it is slowly but it is getting better. The question is: can it do at it’s best better Sound then TU-1X. The answer is pending.

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-01-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 6
Post ID: 7959
Reply to: 7958
Partly to blame
Romy, does the REL use capacitance or inductance tuning?  I was thinking H.  Of course all the old caps are shot.  That's another case where the True Vintage Believers (TVB) are really too funny, when they insist on "original" parts.  IMO, the only issue with parts upgrades in most cases like this one is alignment, where the values all have to be trimmed.  IMO, very few of the old parts are "better"; some, maybe, but very damned few.  This can get right down to tube sockets, wire and even solder joints.  Also, those wonderful old pots often corrode eventually,  so they can be noisy and/or track poorly.  But in cases like the REL, it's the design and over-the-top implementation that set it apart.  We've come a long way since then with most of the parts, and time has often worked its Special Magic on parts that started out OK.

On the "vintage" front, the thing does LOOK cool!  It LOOKS like it should sound good...

Best regards,
Paul S
08-02-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 7
Post ID: 7968
Reply to: 7958
The REL Precedent and Stereo

 Romy the Cat wrote:
I also have some problem with my T85 Multiplex Decoder to read the REL composite signal.  The T85’s decoder read Schwarz’s signal perfectly but it is finicky REL’s signal. I did not figure out yet hat is going on.

I have problems with what audio people say. Ether they deaf or stupid of just run their mouth just for sake of mouth running.  A few days back I was looking for what the knowledgeable audio people say about the REL tuner and I was truly astonished what I read. I was looking for an answer for the problem I had but what I read was evidence the people of there are clueless. The Morons claim that REL Precedent is a phenomenal mono tuner as is but the Precedent as is a nightmare. With the same success one can buy AM radio from 30 and listen it – the identical sound. The Precedent’s output stage is beyond any most disgusting believes but… perhaps it has a good “synergy” with the playbacks and with the reference point of the people who appreciate the Precedent-mono sound.

Then there is Stereo. My problem with Precedent’s stereo sound was why I went into people to see what others say. To me the SU-1X is the reference stereo. The T85 Multiplex Decoder driven by Schwarz has practically identical stereo quality, however when T85 is driven by REL the stereo imagine is very pure. It is not that T85 is bad MPX decoder – it is extremely good I presume that since the REL was made before the 1961 - when FCC announced stereo FM - the REL’s composite signal is not optimum to care MPX signal. I did not see anybody mention it about REL but the funny people say “juts attach a multiplex decoder to REL and you will have it”. Have what? Do those people have any remote sense who a proper FM stereo broadcast shell be presented? The Precedent’s stereo a juts a sad parody, at list in my case, how the FM stereo shell be. I was wondering why.

Upon further investigation, reading the technical articals like this:

http://transmitters.tripod.com/stereo.htm

and consultant with different people I come to the discovery that mono and stereo need different bandwidth from intermittent frequency stage. The REL IM section is fine for mono signal but when REL cares wider bandwidth of stereo signal then it truncates the side-band, introducing HF phase distortions – it is exactly how it sounds. I consulted with Dima and he was laughing saying that it is silly to expect the best sound while caring stereo with IM section that has mono-targeted 250kHz bandwidth. So, what REL need to be able to run any more or less civilized stereo is to widen the bandwidth of intermittent frequency stage to 400kHz.  Then, only then it would worth to look how the REL sounds in full stereo. Without it (if I am correct) the REL is good only for listing the NPR’s  “Wait Wait... Don't Tell Me!” but not good for the real musical broadcasts.

Rgs, Romy the Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-04-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 8
Post ID: 7980
Reply to: 7968
The modification of REL Precedent – go wider.

Figuring out how to switch REL Precedent’s IM bandwidth to more suitable for Stereo operation I was wondering about something else. The 250kHz window though which the REL Precedent looks to the FM band is might be fine for DXing or having good selectivity but from what I see in context of another tuners 250kHz is too narrow range for producing best sound quality. All modern tuners have IM filters tined from 430kHz to 150kHz. Sansui TU-X1 has Wide-400Hz and Narow-200Hz (in fact it sound VERY nice in Narrow). Yamaha 7000 has 430kHz - the widest and the Yamaha T85 has 150kHz – the narrowest. Sure, with shrinking the capture widow makes the selectively of a tuner go all the way up but also the sound quality goes all the way down.  The T85 in Ultra Narrow mode has a phenomenal selectivity but it sound like MP3 player. Tuning to a good station in the Super-wide on T85 mode adds a LOT to sound quality compare to more narrow modes….

 So, why to have in the REL Precedent the 250kHz capture window if wider ranghe would add more to sound quality? I do not need this tuner to catch the live transmission of Florida radio stations broadcasting the high-speed chase of local drag dealers. I needed it to get max sound quality from my very local stations. So, the REL Precedent will be converted to 400Hz IM bandwidth – and it might make it to have the Sansui’s sonic space and the Sansui’s bass. (Bass is dying first with shrinking of IM bandwidth as I can hear).

Rgs, Romy the Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-19-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 9
Post ID: 8083
Reply to: 7980
The REL President on Steroids?

So, to recall everything g the 3 major modifications were done on REL tuner:

1) Change  of Detector diodes from 60 year old glass diodes to 1N5711– with huge advance to Sound

2) Change diodes that come to grids of the limiter stage to 1N5711. The effect not huge  but to sound positive – the LF harmonics got removed from noise and the noise become more uniformed

3) Increase the IM bandwidth from 250kHz to 400kHz - huge advance to Sound as well.

All of those advances in REL did not lead to better sound overall as in a few days the front-end on the REL when down (for own independent reasons). The funny part is that the REL is so good that it sucks signal from antenna… without the front end (the first tube is not there). This crates some noise that prevents to hear the tuner in the way how it might sound. It looks like I know what is the problem was and I can’t wait to get home and to fix it. I really would like to listen how the REL with all that injected adrenalin would sound.  It should not be worse and I do anticipate a very interesting push up sonically against the SU-X1 and Rohde & Schwarz

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-19-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 10
Post ID: 8085
Reply to: 8083
So, are we talking stereo?!?!
Does the added bandwidth mean you have a MPX strategy?

That should be the last hurdle for the REL.  That front end is the bomb!

Best regards,
Paul S
08-19-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 11
Post ID: 8086
Reply to: 8085
I have no MPX strategy anymore…
… and of cause I do not listen FM in mono. I drive REL into Rohde & Schwarz external decoder. The Schwarz has to inputs for composite signal and UFH routers that allow driving the decoder from multiple tuners – very very convenient.

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-19-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 12
Post ID: 8087
Reply to: 8086
Since you can...
Well, that sounds like a very good MPX strategy to me; in any case it's what I'd do, if I were in your shoes...

I have not talked to Mike Z. yet, but I will since I have a few questions for him about local reception strategies and front end options.  Anyway, I seem to recall he went outboard, as well, rather than trying to "fix" the REL.

No need to (re)invent the wheel...

Best regards,
Paul S
08-21-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 13
Post ID: 8091
Reply to: 8083
The crazy REL’s new sensitivity.
Play with REL I made other modification the boosted the REL sensitivity to insane level. I modified the way in which my REL delivers antenna’s signal to REL’s front end. Now my REL has BNC ground lifted antenna jack (I tended to use BNC connectors for everything), then a coax that goes directly to frond-end ground right inside of the front end.

REL_FrontEnd.JPG

The signal wire of the coax soldered directly to the second turned of the very first coil (I got rid the entire primary that was there). What a stunning gain of sensitivity it gave!!! Now REL measures 50-70% signal meter on most of the stations with its top off and without any antenna attached. When I put the cover on and close the tuber then I need to attenuate my local stations to 60-50dB (!!!!) to get OK reception. In some case the tune with max out signal get 2-3 stations at the same time and driving the signal doe to 30-40dB I completely get rid of the second station and then another 20dB doe I loosing the noise on the only station the left. So, with this insane sensitivity the REL dives into deep-deep overload and the 5 stages of limiter cannot handle it. Wow! It would be fun if turns out that I need to use my REL with pulled out tubes in IM stage…. Still. Trying to make the new hyper-sensitive REL to behave…

The caT


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-22-2008 Post does not mapped to Knowledge Tree
Wojtek
Pinckney (MI), United States
Posts 158
Joined on 09-01-2005

Post #: 14
Post ID: 8093
Reply to: 8091
Oh ,Thanks for that thread! Dima are you watching it ?

I'm strugling with dreaded Mcintosh Mr67 tuner . I borrowed one from a friend and it was very nice ;clear , crisp , dynamic so I went out and bought one for myself . It sounds like a mud and matches 100% of your description of average tube tuner sound -vintage POS. I don't know what kind of mods had unit I've borrowed . My friend already sold it.
Dima if you're around could you suggest some mods to improve performance of that unit ? It is not collectible (chrome is gone from chassis Wink so I can hack it , use only front end etc. If that's to much to ask for thanks anyway for the hint with detector diodes and decoupling the meter.
Regards, W

08-22-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 15
Post ID: 8094
Reply to: 8093
The damn tubes tuners.
I have no idea where this saga with REL leads me. Even though I do have substantial sonic improvement over the original REL version I still do not know if I like this tuner all together. The 50 years all tube tuner with 17 tubes is very freaky thing. I still have some tuner owned noise that I would like do not have. The damn thing sounds very deferent with the change of the few tubes (particularly oscillator and the last tube of limiter). The tube sockets all are garbage and twisting the tubes in their stockers do changes sound of the tuner to a degree. As now REL sounds more or less OK but kind of unstable. My SS tuner beat if with large degree. Perhaps the REL at this point need a recalibration and viewing by somebody who has more RF skills then I do? I am considering it. At this point REL is more pain in ass then results.

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
08-23-2008 Post does not mapped to Knowledge Tree
deemon
Posts 23
Joined on 05-25-2004

Post #: 16
Post ID: 8096
Reply to: 8093
MR67
Hi , Wojtek !

Of course , I have some ideas how to modify this tuner , but before doing it you need to check if it operates correctly ! I mean tubes health , power supply operation , DC voltages on testpoints , LC tanks alignment , etc . You see , if we modify the faulty or bad aligned circuit - we can go to wrong direction . By the way , the great device for tuner alignment is RF sweep generator ..... do you have it ? If you do , it's very good !  But if not - you can control only DC parameters , and cannot find out possible problems in RF and IF stages .....

Best regards
Dima
08-24-2008 Post does not mapped to Knowledge Tree
Wojtek
Pinckney (MI), United States
Posts 158
Joined on 09-01-2005

Post #: 17
Post ID: 8098
Reply to: 8096
Thanks Dima
I don't have RF sweep generator but it's fairly easy to source here. I will take the tuner to local FM tuner tech to re-check alignment and we'll take it from there in a couple of weeks. I will have to read more about RF circuits trough this time .  Thanks again and best regards
W.
07-30-2009 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 18
Post ID: 11236
Reply to: 8094
Bye-bye REL Precedent.
fiogf49gjkf0d

 Romy the Cat wrote:
I have no idea where this saga with REL leads me. Even though I do have substantial sonic improvement over the original REL version I still do not know if I like this tuner all together. The 50 years all tube tuner with 17 tubes is very freaky thing. I still have some tuner owned noise that I would like do not have. The damn thing sounds very deferent with the change of the few tubes (particularly oscillator and the last tube of limiter). The tube sockets all are garbage and twisting the tubes in their stockers do changes sound of the tuner to a degree. As now REL sounds more or less OK but kind of unstable. My SS tuner beat if with large degree. Perhaps the REL at this point need a recalibration and viewing by somebody who has more RF skills then I do? I am considering it. At this point REL is more pain in ass then results. 

Well, what can I say? My SS turners turn out to be WAY more superior then REL, even after two alignments.  If to consider that REL is more sophisticated and more properly made tuner then all of those McIntoshs, Marantzs, Leaks, Scotts and Fishers then it was a good journey into SS vs. tube tuners debate.

It is sad in a way as I had a lot of expectations from REL, furthermore my REL had SS output stage and tube-made were only the RF stages. Still the R&S and Sansui beat it, primary in bass, dynamics and noise. With all sadness I decided to let REL to go. The legend did not prove itself….

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
07-30-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 19
Post ID: 11237
Reply to: 11236
Collectors Item
fiogf49gjkf0d
Do I recall that the REL had a fairly "unusual" tuning section - among its many features that were (and still are) novel for a "civilian" tuner - , and that many of those old parts were not only top, SOTA mil-spec back then but most of them were also "critical value", matched and trimmed to within a gnat's eyelash?  I can't imagine trying to work on that thing.

But I'll bet you didn't have any trouble selling the Legendary REL Precedent...  probably crowing and pics posted already at Vintage Sufferers website...

BTW, did you ever figure out how to get it to do stereo?

Best regards,
Paul S
07-31-2009 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 20
Post ID: 11239
Reply to: 11237
REL Precedent on the Moon!!!
fiogf49gjkf0d
 Paul S wrote:
Do I recall that the REL had a fairly "unusual" tuning section - among its many features that were (and still are) novel for a "civilian" tuner - , and that many of those old parts were not only top, SOTA mil-spec back then but most of them were also "critical value", matched and trimmed to within a gnat's eyelash?  I can't imagine trying to work on that thing.

Those are ridicules fantasies. There is absolutely nothing unusual in REL, nothing none-civilian: neither in design nor in implementation. It is a tuner as any other tuners made at that time, just designed better.  Those foolish rumors most likely started from a Moron at FM Tuners site who called that REL was made like military receivers. Well, there are reasons why I call him a Moron. What would the next: he story that REL was caring the communication between Huston and Neil Armstrong from Gemini 8?

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
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