Date   

Re: Lies, Damned Lies, and 10B specs

John <jbyrns@...>
 

--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:

I wonder about the 150dB selectivity claim even in terms of signals
getting
through the front end without overloading it.
It also makes you wonder how they measured 150 dB? Even if it does
have 150 dB alternate channel selectivity, I have to wonder what you
would use it for? It seems to me that if you are really trying to
pull stations out of a crowded band, excellent adjacent channel
selectivity would be more important, and useful, than an over the top
alternate channel selectivity number. Also, as McIntosh noted when
they first came out with a super selective tuner, selectivity is of
limited value if there are spurious response products being generated
in the front end, the front end must be tended to first.

Front end overload is another
matter of controversy regarding the 10b. One Audio Asylum poster
insists
that the 10b front end has terrible 3rd harmonic distortion. That
sounds
like some sort of overload to me. That poster recounts the story
of how
he sent his 10b back to the factory and they insisted it was
operating
correctly.
I don't know what "Audio Asylum" is, and don't believe I have ever
posted there, but that sounds suspiciously like the story of my 10B,
and the 3rd order IM problem in its front-end. I wonder if someone
posted my 10B story there? If there is another person with the same
experience as mine, I would be interested in hearing about it.

John


Rant on Muting

Charles Peterson <charlesp@...>
 

Actually, my earlier rant on muting was very short in earlier post because I
edited most of it out, but then forgot to edit it out of the subject line.

Muting as commonly implemented is not only an almost useless feature to me, it
is positively subversive. It keeps you from discovering how many stations you
can actually receive. It keeps you in the rut of going from big station A to
big station B, which is exactly what the big media conglomerates want you to do.
(Or, better yet, just keep it at big station A because you don't know about
anything else.)

First, I believe that Muting is basically a "sissified" feature. Back when men
were REAL men and women were REAL women, tuners didn't have muting. Then (about
1960) people objected to the noise in between FM stations, and so the FM Muting
feature was born. It was also the first non-user-serviceable part to fail on
every tube tuner...so perhaps it was really a form of planned obsolescence.
(And, of course, you had to trade in your earlier tuner w/o muting to get
muting in the first place; you had to because everyone else had it...)

A better way to deal with this IMHO is simply to have a volume control on the
front panel of the tuner. Then you employ two-handed tuner operation. Reduce
the volume while tuning, then turn it up to the proper level for the station you
have tuned to (which depends on how much compression they're using, etc.).

This is the way I think muting _should_ work if there is going to be muting. It
should be something like a 20-30dB attenuation. Then, you can still "hear" what
you are doing while tuning, and hear the little stations you might not have
known about, but not be overwhelmed by massive noise (which, I admit, can get
pretty overwhelming if you were listening to music at "realistic" levels) in
between stations.

As it is, with full muting engaged, you have to keep your eyes on the dial and
the meters and ignore your ears. Better hope your dial calibration is perfect.
If it is far from perfect (which has been all too frequently the case) you have
to hunt around, to find the station you want, if you even know what exact
frequency it is at, and then get it nearly right on before you hear anything.
Then, more often than not it seems, you've tuned in the wrong station so you
have to hunt around in the dark again. You've got meters and a dial to watch,
but they're not really telling you what you want to know. You want to know
what's there.

That's a good metaphor for tuning with Muting engaged...hunting around in
the dark.

The Fisher 80 tuners (mid to late 1950's) used a different technique...
variable strong AFC. In a metropolitan area, the AFC when cranked all the way
up is so strong you can "flip" from one station to another with no space in
between. (And, it always makes a cute whoop sound whenever that happens. That
whoop sound might not be so good on subwoofers, though.) I liked that better
than Muting; you never have to hunt around in the dark. You can dial down the
AFC to find the smaller stations if you want to. But there is still enough
noise that you need a front panel volume control, which most of the 80 series
tuners unfortunately lacked. In the end, I'd prefer having a front panel volume
control.

Muting actually has one fairly useful purpose. If the station goes off the air,
and you had been playing it at a fairly high volume level, you will get so much
noise it might do something bad, like destroy your speakers. That happened to
me once. So muting is actually more useful AFTER tuning, not DURING tuning.
The alternative to muting is, once again, simply to turn the volume down (if not
off) whenever you leave the area.

I forgot to agree wholeheartedly with the Muting point. And perhaps
my #1 pet peeve: muting and mono/stereo on the same switch, making it
impossible to choose to listen to stations in weak stereo. Amazing
how many "good" tuners (like some top Pioneers) did that. -Eric
If it didn't do that, you might not like the "Auto" stereo either. There's
nothing more annoying that having the "Auto" stereo flip back and forth on
marginal stations. This can be much more distracting that the stereo noise
itself. Pioneer's approach prevents that, if nothing else. Better solutions
involve letting you "lock-in" stereo; I believe the Sequerra allows that, and
I'm pretty sure you can get the Onkyo 9090 II to do this if you're persistent
enough. Personally, I listen to the weakest stations in mono anyway.


Re: Hello Group

James Yerkes swbell <yerkesj@...>
 

HELLO FM TUNER GROUP!

Have an interesting question, was surfing through the accuphase vintage tuner site and saw the accuphase T-18 and of course the t-109, not really familiar with the T11 that they show, is this a european version of the T-108 it looks quite similiar in size and layout on the dial.

In this respect does anyone know if there any viuntage hi-end shops in Japan that may carry goodies such as the T-108 and T11 accuphase tuners, if anyone has any information on a web site would be most appreciative. e-mail address is: yerkesj@swbell.net

Thank you very much, jim St Louis, MO

PS I am familiar with e-bay but mainly seem to see the t-100 and T101 accuphase tuners only

wjcorbin@yahoo.com wrote:

I just found the group yesterday while browsing over at AudioAsylum. Within the last year I have become very interested in FM tuners. I have always been interested in audio and music in general so finding this group is like heaven.

Currently I have a Yamaha TX-930 purchased off of EBAY with a Magnum-Dynalab MD205 signal sleuth. For antennas I have a Fanfare FM-2G whip and an APS-9 yagi. I have a couple of questions of the members here.

First, I have seen much acclaim for the McIntosh MR77, MR78, and MR80. I have heard these tuners have a gorgeous sound. I am looking for the best sound quality I can get. My question is, would any of these tuners be a significant improvement over the TX-930 sonically. Yes, I know these tuners are significantly more expensive than the TX-930 on the used market, but I am willing to spring for it if there are perceivable benefits in sound quality.

My second question, what tuners do you guys have, just curious! Thanks for your time;-)



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Hello Group

William Corbin
 

I just found the group yesterday while browsing over at AudioAsylum.
Within the last year I have become very interested in FM tuners. I
have always been interested in audio and music in general so finding
this group is like heaven.

Currently I have a Yamaha TX-930 purchased off of EBAY with a
Magnum-Dynalab MD205 signal sleuth. For antennas I have a Fanfare
FM-2G whip and an APS-9 yagi. I have a couple of questions of the
members here.

First, I have seen much acclaim for the McIntosh MR77, MR78, and MR80.
I have heard these tuners have a gorgeous sound. I am looking for
the best sound quality I can get. My question is, would any of these
tuners be a significant improvement over the TX-930 sonically. Yes, I
know these tuners are significantly more expensive than the TX-930 on
the used market, but I am willing to spring for it if there are
perceivable benefits in sound quality.

My second question, what tuners do you guys have, just curious!
Thanks for your time;-)


Re: Lies, Damned Lies, and 10B specs

Charles Peterson <charlesp@...>
 

Charles - Good muckraking - keep it up!

Our original writeup of the 10B on the TunerInfo site expressed strong
doubt about those very specs, but then I had an interesting email
exchange with Ben Blish (during which he made the statement about the
2130's dining habits). According to Ben, every 10B leaves the factory
meeting those specs, and he says that his own 10B has been measured
and meets them - yet there are other design limitations of the 10B
that make the 2130 a better DX tuner. I'll ask Ben if he'd mind if I
posted his entire email here. -Eric
I'd sure like to see that. I was going to email Ben after making this
post to hear what he had to say. I posted similar comments to the
Audio Asylum Vintage Audio section a month ago and didn't get much response.
That was before I dug up the Stereo Review review, which doesn't say
much either but is great fun to make fun of.

I noticed my post here had one error. When I said the "IHF useable selectivity"
was measured as 2.1 microvolts, I obviously meant the "IHF useable sensitivity."

I wonder about the 150dB selectivity claim even in terms of signals getting
through the front end without overloading it. Front end overload is another
matter of controversy regarding the 10b. One Audio Asylum poster insists
that the 10b front end has terrible 3rd harmonic distortion. That sounds
like some sort of overload to me. That poster recounts the story of how
he sent his 10b back to the factory and they insisted it was operating
correctly.


Re: Lies, Damned Lies, and 10B specs

fades@...
 

Charles - Good muckraking - keep it up!

Our original writeup of the 10B on the TunerInfo site expressed strong
doubt about those very specs, but then I had an interesting email
exchange with Ben Blish (during which he made the statement about the
2130's dining habits). According to Ben, every 10B leaves the factory
meeting those specs, and he says that his own 10B has been measured
and meets them - yet there are other design limitations of the 10B
that make the 2130 a better DX tuner. I'll ask Ben if he'd mind if I
posted his entire email here. -Eric

--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:
The specs for the Marantz 10b tuner now shown on the classic-audio
site
list the alternate channel selectivity as 150dB and the adjacent
channel
selectivity as 42dB. These specs (which I believe are from the
manufacturer)
can't possible be correct, can they? What is the actual measured
selectivity
of the 10b?

I've never heard of any other tuner having 150dB alternate channel
selectivity.
Not even close. And while there are a handful (MR78 for one) that
can beat
42dB adjacent channel selectivity, it's hard to believe that the 10B
does.

Hoping it would address this void, I dug up the Stereo Review of the
Marantz
10B (December 1965). This has to be one of the most worthless
reviews ever
penned by Julian Hirsch. It's little more than a puff piece, full
of
descriptions like "in a class by itself," at least one important
factual
error ("Butterworth-filter i.f."), and excuses ("I could do no more
than
ascertain the limits of my own test instruments"). And NOT ONE WORD
about
the actual measured selectivity or capture ratio. (The IHF useable
selectivity
was measured as 2.1 microvolts. That doesn't say much. The
manufacturers
spec for "RF Sensitivity" is 2.0 microvolts.)

Here the one thing Julian said relating to selectivity, which
doesn't answer
anything:

"The Butterworth-filter i.f. section never needs alignment, and is
unaffected
by tube changes. It has a flat, phase-linear 200-kc pass band, with
skirt
slopes of 108dB per octave. This far exceeds the performance
obtained with
ordinary i.f. transformers, and makes adjacent-channel interference
a most
unlikely occurance."

What does "108dB per octave" tell us about the selectivity? Does
anyone know?

As far as adjacent-channel interference being unlikely, that is
definitely a
lie. The Butterworth thing is inaccurate. Julian should have known
that
"Butterworth" doesn't go along with "phase-linear." A suitable
translation of
the comments about alignment might be:

"You'll have to hope and pray it never needs alignment, because when
it does,
you'll have to send it to one of the few people in the world who can
do it
properly, and pay them all the money you've got to do it right."

As I understand it, the 10B was DESIGNED not to require much
alignment
(because of how difficult it is) with a relatively simple
capacitance
compensation for each IF tube. If someone messes with the actual
alignment,
which was purposefully made hard to get to, you might be in deep
trouble.
Of course, after 40 years, even the actual IF alignment might need
some work.

I wonder if Julian actually measured the 10B selectivity, but simply
didn't have
the nerve to report it. He certainly measured the selectivity of
later tuners,
such as measuring the Sansui TU-9900 as having 100dB alternate
channel
selectivity, which very well supports the manufacturer's spec of
90dB.


Lies, Damned Lies, and 10B specs

Charles Peterson <charlesp@...>
 

The specs for the Marantz 10b tuner now shown on the classic-audio site
list the alternate channel selectivity as 150dB and the adjacent channel
selectivity as 42dB. These specs (which I believe are from the manufacturer)
can't possible be correct, can they? What is the actual measured selectivity
of the 10b?

I've never heard of any other tuner having 150dB alternate channel selectivity.
Not even close. And while there are a handful (MR78 for one) that can beat
42dB adjacent channel selectivity, it's hard to believe that the 10B does.

Hoping it would address this void, I dug up the Stereo Review of the Marantz
10B (December 1965). This has to be one of the most worthless reviews ever
penned by Julian Hirsch. It's little more than a puff piece, full of
descriptions like "in a class by itself," at least one important factual
error ("Butterworth-filter i.f."), and excuses ("I could do no more than
ascertain the limits of my own test instruments"). And NOT ONE WORD about
the actual measured selectivity or capture ratio. (The IHF useable selectivity
was measured as 2.1 microvolts. That doesn't say much. The manufacturers
spec for "RF Sensitivity" is 2.0 microvolts.)

Here the one thing Julian said relating to selectivity, which doesn't answer
anything:

"The Butterworth-filter i.f. section never needs alignment, and is unaffected
by tube changes. It has a flat, phase-linear 200-kc pass band, with skirt
slopes of 108dB per octave. This far exceeds the performance obtained with
ordinary i.f. transformers, and makes adjacent-channel interference a most
unlikely occurance."

What does "108dB per octave" tell us about the selectivity? Does anyone know?

As far as adjacent-channel interference being unlikely, that is definitely a
lie. The Butterworth thing is inaccurate. Julian should have known that
"Butterworth" doesn't go along with "phase-linear." A suitable translation of
the comments about alignment might be:

"You'll have to hope and pray it never needs alignment, because when it does,
you'll have to send it to one of the few people in the world who can do it
properly, and pay them all the money you've got to do it right."

As I understand it, the 10B was DESIGNED not to require much alignment
(because of how difficult it is) with a relatively simple capacitance
compensation for each IF tube. If someone messes with the actual alignment,
which was purposefully made hard to get to, you might be in deep trouble.
Of course, after 40 years, even the actual IF alignment might need some work.

I wonder if Julian actually measured the 10B selectivity, but simply didn't have
the nerve to report it. He certainly measured the selectivity of later tuners,
such as measuring the Sansui TU-9900 as having 100dB alternate channel
selectivity, which very well supports the manufacturer's spec of >90dB.


Short rant on Muting

fades@...
 

I forgot to agree wholeheartedly with the Muting point. And perhaps
my #1 pet peeve: muting and mono/stereo on the same switch, making it
impossible to choose to listen to stations in weak stereo. Amazing
how many "good" tuners (like some top Pioneers) did that. -Eric


Re: Where's the MR77 IF switch?

fades@...
 

We hang our collective heads in shame... I'm not sure where I got
that bad info, but it's gone now.
http://www.geocities.com/tunerinfo/#mcintosh

Thanks, guys. -Eric

(--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:
The Tunerinfo site must be wrong, then, because it says "Not quite
an MR 78
(two IF settings rather than 3, for one thing..."

With only one IF setting, the MR77 has a most incredible compromise
IF,
giving 90dB/47dB alt/adj selectivity with 0.2% distortion. While a
fair
number of tuners achieve the same alt selectivity in their "narrow"
mode, maybe a handful can achieve the same adj selectivity in any
mode
without modification.

It is, in fact, narrower than the MR78's middle IF mode, but gives
the same
rated distortion nonetheless.

I see also the MR77 was introduced in 1970 and the MR78 was
introduced in
1972, which is also pretty amazing.


There is no IF selectivity switch on the MR-77, that's what the
MR-78
is all about! The MR-78 is an MR-77 with some added bells and
whistles, the switchable IF selectivity is the most important one,
and
the only one I can remember.


Re: Accuphase T-107 - Resolution

Gary Aigen
 

Well, I went and heard this tuner this evening and did a fairly good
comparison with my NAD 4155 which I brought with me. The difference
was surprising to me: the Accuphase was more open, revealing, with
better soundstage as well as better bass and top-end. You probably
can guess that I came home with it. The best part is that my wife
heard the difference as soon as I set it up and was pleased that I
bought it. Now if I could only compare it to a Sansui 9900 or an MR-
78.
Gary


--- In FMtuners@y..., aigenga@y... wrote:
Does anyone have any knowledge of this tuner - how does it sound in
comparison with some of the fine tuners discussed in this forum?

I have an opportunity to buy this tuner for $595 in mint
condition.
I will be auditioning it on Teusday and hopefully get to compare it
to a Magnum Dynalabs model, but it will be a limited listening
opportunity.

Thanks for any info or leads on info (reviews, etc,).
Gary


Re: Where's the MR77 IF switch?

John <jbyrns@...>
 

You can't always believe everything you read, just because it's in
print! The numbers you quote for the MR-77 are the same ones that
are
on Roger Russell's page, but I suspect they are wrong. I am pretty
sure that the MR-74, MR-77, and MR-78 all used the same basic "RIMO"
filter for the normal selectivity setting, and they should all have
similar selectivity figures when set for "normal" selectivity.

John

--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:
The Tunerinfo site must be wrong, then, because it says "Not quite
an MR 78
(two IF settings rather than 3, for one thing..."

With only one IF setting, the MR77 has a most incredible compromise
IF,
giving 90dB/47dB alt/adj selectivity with 0.2% distortion. While a
fair
number of tuners achieve the same alt selectivity in their "narrow"
mode, maybe a handful can achieve the same adj selectivity in any
mode
without modification.

It is, in fact, narrower than the MR78's middle IF mode, but gives
the same
rated distortion nonetheless.

I see also the MR77 was introduced in 1970 and the MR78 was
introduced in
1972, which is also pretty amazing.


There is no IF selectivity switch on the MR-77, that's what the
MR-78
is all about! The MR-78 is an MR-77 with some added bells and
whistles, the switchable IF selectivity is the most important one,
and
the only one I can remember.


Re: Sherwood Micro CPU-100 Tuner Literature

gfredsen@...
 

yes, according to the CPI the buying power of US$1000 in 1978 would
have to be equal to $2750 today. Somebody just paid $2025 for that
TUX1 (?) Sansui tuner on Ebay and there is another one on there now.
it will be fun to see how much it brings. Have you compared the
Sherwood to other tuners as to sensitivity and fidelty? A very
interesting tuner, but can it be repaired if something goes wrong.


--- In FMtuners@y..., gentry@i... wrote:
About a year ago I acquired a Sherwood Micro-CPU 100 FM tuner. This
was advertised as the first computer controlled FM tuner. It's
still
performing well coupled with a Sherwood HP2000 integrated amp. The
seller sent the original owner's manual and some advertising
literature with the tuner. I've scanned and uploaded the Stereo
Review of the tuner and a Sherwood brochure.

I like the sound and enjoy it a lot. Does anyone else have and
additional information on this tuner. I can scan and send the
owner's
manual if there's any interest.

I also got a copy of the original bill of sale and cashier's check
used for the purchase in 1978. The original price was $1000 a chunk
of change today, but really a lot in 1978 for an FM only tuner.


Re: Where's the MR77 IF switch?

Charles Peterson <charlesp@...>
 

The Tunerinfo site must be wrong, then, because it says "Not quite an MR 78
(two IF settings rather than 3, for one thing..."

With only one IF setting, the MR77 has a most incredible compromise IF,
giving 90dB/47dB alt/adj selectivity with 0.2% distortion. While a fair
number of tuners achieve the same alt selectivity in their "narrow"
mode, maybe a handful can achieve the same adj selectivity in any mode
without modification.

It is, in fact, narrower than the MR78's middle IF mode, but gives the same
rated distortion nonetheless.

I see also the MR77 was introduced in 1970 and the MR78 was introduced in
1972, which is also pretty amazing.

There is no IF selectivity switch on the MR-77, that's what the MR-78
is all about! The MR-78 is an MR-77 with some added bells and
whistles, the switchable IF selectivity is the most important one,
and
the only one I can remember.


Re: Where's the MR77 IF switch? Short rant on Mut

John <jbyrns@...>
 

There is no IF selectivity switch on the MR-77, that's what the MR-78
is all about! The MR-78 is an MR-77 with some added bells and
whistles, the switchable IF selectivity is the most important one,
and
the only one I can remember.

John

--- In FMtuners@y..., Charles Peterson <charlesp@d...> wrote:
Now that the MR78 trades for a small fortune on eBay, the lesser
MR77 is
getting attention as a near-equal substitute. When I get around to
buying
costlier tuners, this model is near the top of my list.

I see one closing out today on eBay, in fact, currently at $400.

But where oh where is the IF selectivity switch? There doesn't
appear to
be such a switch on the front panel, only mode selector, stereo
filter,
muting, volume, and tuning.

If it's tied to the muting switch, I hope you get the narrow
bandwith in the
"Muting Off" position. In most cases, I think the proper selection
for muting
is OFF, if not REMOVED FROM UNIT.

I note that the ultimate selectivity is significantly (if not
substantially)
better on the MR78. MR78 maximum adjacent channel selectivity is
55dB while
MR77 adjacent channel selectivity is "only" 47dB, a full 8dB
difference. Of
course, even 47dB is pretty incredible adjacent channel
selectivity, with even
other "supertuners" like my Sansui TU-9900 only specing at 22dB.


Where's the MR77 IF switch? Short rant on Mut

Charles Peterson <charlesp@...>
 

Now that the MR78 trades for a small fortune on eBay, the lesser MR77 is
getting attention as a near-equal substitute. When I get around to buying
costlier tuners, this model is near the top of my list.

I see one closing out today on eBay, in fact, currently at $400.

But where oh where is the IF selectivity switch? There doesn't appear to
be such a switch on the front panel, only mode selector, stereo filter,
muting, volume, and tuning.

If it's tied to the muting switch, I hope you get the narrow bandwith in the
"Muting Off" position. In most cases, I think the proper selection for muting
is OFF, if not REMOVED FROM UNIT.

I note that the ultimate selectivity is significantly (if not substantially)
better on the MR78. MR78 maximum adjacent channel selectivity is 55dB while
MR77 adjacent channel selectivity is "only" 47dB, a full 8dB difference. Of
course, even 47dB is pretty incredible adjacent channel selectivity, with even
other "supertuners" like my Sansui TU-9900 only specing at 22dB.


Sherwood Micro CPU-100 Tuner Literature

gentry@...
 

About a year ago I acquired a Sherwood Micro-CPU 100 FM tuner. This
was advertised as the first computer controlled FM tuner. It's still
performing well coupled with a Sherwood HP2000 integrated amp. The
seller sent the original owner's manual and some advertising
literature with the tuner. I've scanned and uploaded the Stereo
Review of the tuner and a Sherwood brochure.

I like the sound and enjoy it a lot. Does anyone else have and
additional information on this tuner. I can scan and send the owner's
manual if there's any interest.

I also got a copy of the original bill of sale and cashier's check
used for the purchase in 1978. The original price was $1000 a chunk
of change today, but really a lot in 1978 for an FM only tuner.


Re: 70s Yamaha

James Yerkes swbell <yerkesj@...>
 

Speaking of the Yamaha CR2020 receiver, there is one now currently available for sale beautifully resored at austin  stereo in austin, Texas, beautifully restored price also of 600.00. web site is as follows:  www.austinstereo.com  lots of other really nice vintage hifi gear.

jim Yerkes, st louis, MO

Scott Guthrie wrote:

Thanks! For 20 years, I've wondered what the NFB stood
for. (you'd think I would've figured it out by now)
I think the CR-2020 used it also.

Yamaha refers to the circuitry as "PLL NFB."  The
"NFB" stands for "Negative
Feedback," something which doesn't generate a lot of
ad copy these days.
Somehow, Yamaha applies NFB around the PLL chip
through the discrete
transistors. I'm a believer in using as little NFB
as possible (or none),
but this circuit does seem to work in generating a
good sound.





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Re: 70s Yamaha

Scott Guthrie <scottallwave@...>
 

Thanks! For 20 years, I've wondered what the NFB stood
for. (you'd think I would've figured it out by now)
I think the CR-2020 used it also.

Yamaha refers to the circuitry as "PLL NFB." The
"NFB" stands for "Negative
Feedback," something which doesn't generate a lot of
ad copy these days.
Somehow, Yamaha applies NFB around the PLL chip
through the discrete
transistors. I'm a believer in using as little NFB
as possible (or none),
but this circuit does seem to work in generating a
good sound.



__________________________________________________
Do You Yahoo!?
Yahoo! GeoCities - quick and easy web site hosting, just $8.95/month.
http://geocities.yahoo.com/ps/info1


Re: 70s Yamaha

Charles Peterson <charlesp@...>
 

Does anyone own a 70s Yamaha? Like a CT 600 or 800 series? I'm
curious to know if they used discreet transistors or op-amps in the
audio stage. The question is aimed at maybe improving the audio
stage, not DXing. Thanks. jim...........
I just purchased a CT-1010 on ebay about a month ago to add to my collection of
tuners. It is a very nice sounding tuner, almost on par with my Sansui TU-9900
in audio quality (neither are as nice sounding as my tubed tuners however).
Tuning performance is OK but not quite as good as Kenwood KT-7500 (which
itself is not as good as TU-9900).

The output stage features discrete transistors AND a PLL chip. Ultimately,
the audio is buffered by discrete transistors, not op amps.

Yamaha refers to the circuitry as "PLL NFB." The "NFB" stands for "Negative
Feedback," something which doesn't generate a lot of ad copy these days.
Somehow, Yamaha applies NFB around the PLL chip through the discrete
transistors. I'm a believer in using as little NFB as possible (or none),
but this circuit does seem to work in generating a good sound.


Onkyo T-4055

gfredsen@...
 

Anyone have any experiance with this tuner? I remember that it was
reviewed very favorably in a comparative test in Absolute Sound (for
what thats worth)in the mid '70s. It seems very sensitive and
rejects the powerful transmitter that is about one mile from where I
live. It does not sound as good, to my ears, as my valved Sherwood
S3000V. The Onk has a noise filter and muting and I just wonder if
the fidelity could be made a great deal better by new caps and the
other mods mentioned on the Tuner Info site. It has fixed or
variable volume and scope outputs.
Thank you for providing this site,
Greg