Hello, Is there somebody knows about Dynaco transistor amplifier type TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?
How about compare it with a Dynaco with tubes.
Regards Lars

On Sun, 1 Aug 2004 16:02:49 +0200, "Lars Brandt"
wrote:

Hello, Is there somebody knows about Dynaco transistor amplifier type TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?
How about compare it with a Dynaco with tubes.

These two were among the worst-sounding devices that Dyna ever made. I
would not bother with them except for utility/background.

Kal

Is it because it's transistor? Haven't Dynaco done a good transistor stereo
amplifier?

Lars


"Kalman Rubinson" skrev i meddelandet
...
On Sun, 1 Aug 2004 16:02:49 +0200, "Lars Brandt"
wrote:

Hello, Is there somebody knows about Dynaco transistor amplifier type
TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?
How about compare it with a Dynaco with tubes.

These two were among the worst-sounding devices that Dyna ever made. I
would not bother with them except for utility/background.

Kal

On Sun, 01 Aug 2004 20:11:11 GMT, "Lars Brandt"
wrote:

Is it because it's transistor? Haven't Dynaco done a good transistor stereo
amplifier?

These were Dyna's very first transistor devices and were lauded by
some simply because they were not completely terrible. There were low
expectations, like there are today for IC power amps.

I owned both. They worked but were inferior to the Dyna tube units
they replaced and inferior to the later Dyna transistor units.

Kal



Lars


"Kalman Rubinson" skrev i meddelandet
.. .
On Sun, 1 Aug 2004 16:02:49 +0200, "Lars Brandt"
wrote:

Hello, Is there somebody knows about Dynaco transistor amplifier type
TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?
How about compare it with a Dynaco with tubes.

These two were among the worst-sounding devices that Dyna ever made. I
would not bother with them except for utility/background.

Kal

Lars,

The Dyna PAT-4 (not TAP-4) will get no awards for sound quality. They
have several neat features if you need them, like microphone inputs
(labeled "Special") as I recall. They are reasonably trouble free,
except for the usual noisy switches and controls that you find on any 30
year old preamp.

The ST-120 is not an amp that I'd bother with. At this age, they often
have bad electrolytic capacitors. The input coupling caps can cause the
unit to oscillate and take out the output transistors. Even when they
are working perfectly, they don't sound great. OK for background or PA
work, not something that I'd go out of my way to listen to.

On either model the unit might have been built by the factory or as a
kit. The kits vary widely in quality because of the ability of the
builder. I've seen them range from "it's amazing it ever worked at
all" to "it's better than any of them that the factory built".

Regards,
Tim Schwartz


Lars Brandt wrote:

Hello, Is there somebody knows about Dynaco transistor amplifier type TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?
How about compare it with a Dynaco with tubes.
Regards Lars

"Lars Brandt" wrote in message ...
Hello, Is there somebody knows about Dynaco transistor amplifier type TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?

Listen to the Dynaco gear and decide if you like it. But newer gear
will probably sound better.

How about compare it with a Dynaco with tubes.

Try asking in:

rec.audio.tubes

There is a lot of mystique about tube gear. Many people like and use
the old Dynaco tube amps, and many people modify them to improve the
sound. A Dynaco tube amp will cost you more money and require more
maintenance and the Dynaco solid-state hardware.

If you're interested in sound quality, I think the NAD gear will be a
better choice for you. If I had the choice of any of the brands you
mention, I would choose NAD.

Regards Lars

Thank you for all the comments. I have got a some inputs:
That todays IC stereo amplifier is at least as good as 1970s Dynaco (PAT-4,
ST-120).
But when I heard this Dynaco home at a friend 1974 I think it sounds better
than even a Marantz reciever,better than everything I have listened to.
Regards
La
"N" skrev i meddelandet
om...
"Lars Brandt" wrote in message
...
Hello, Is there somebody knows about Dynaco transistor amplifier type
TAP-4
and ST-120. Is it good? What amlifier sounds best between todays cheaper
amplifier from NAD.
Can an old Dynaco sound good today from 1970?

Listen to the Dynaco gear and decide if you like it. But newer gear
will probably sound better.

How about compare it with a Dynaco with tubes.

Try asking in:

rec.audio.tubes

There is a lot of mystique about tube gear. Many people like and use
the old Dynaco tube amps, and many people modify them to improve the
sound. A Dynaco tube amp will cost you more money and require more
maintenance and the Dynaco solid-state hardware.

If you're interested in sound quality, I think the NAD gear will be a
better choice for you. If I had the choice of any of the brands you
mention, I would choose NAD.

Regards Lars

Lars -

First let me say that the speakers are the most important part of the
audio system, with perfect speakers, a system can sound marvelous;
without great speakers a $100,000 amplifier can be made to sound just
plain awful...

Still great speakers do need a decent preamp and power amplifier, or
the sound can be very compromised, muffled, unclear, and distorted.

So you do need all three: speakers, preamp, power amp to be at a very
high quality level, or in some instances, where their complementary or
non-complementary imperfections tend to balance out...

In these old 1970's Dynaco transistor units, the sound could be very
variable, I highly dispute that they were ALWAYS "bad".

The Preamp PAT-4 was a very simple circuit, but it could suffer
sonically as they were built with the cheapest capacitors money could
buy... It usually does not sound good when compared to the prior
PAS-3x tube Preamp. The PAS-3x can even be improved with better caps,
and this tube preamp is still known for its decent sound some 40 years
later...

Regarding the Stereo 120's, there were something like 100,000+ of
these sets made, and most were kits assembled by people who could be
anywhere along the bell curve from numb-nut-techie-wannabee's to very
competent in terms of soldering and assembly...

Second, in the Stereo 120 there were many variations of parts, and due
to the minimalist design, there was a very great "interaction" among
the parts, which resulted in a wide range of amps with differing
sounds. My own opinion, some Dynaco Stereo 120's sounded excellent,
some sounded thin, tinny, and bad.

Now in order to charactorize them all, they first would have to be
working properly... Some transistors are not forever. Some lose
"beta" gain, and thus fail slowly over time. I've seen some Stereo
120's with bad British BC-108a input transistors, and thus their sound
becomes bad, as they are no longer working properly. Also, some caps
go bad after 15, 30, or 35 years, this can also mess up the sound ( or
account for a complete lack of it ).

When talking about sets that are "WORKING PROPERLY", I find the
not-too-early Stereo 120's are perhaps the best. These have either the
BC-108a or BC-237a input transistors, electrolytic caps; round metal
transistors for drivers in the "killer-dog-collar" heat sinks, brown
phenolic boards, and house numbered 2N3055 output transistors. They
can sound excellent. It is these which are perhaps the best examples
in this genre for a stock, original, amplifier. At a very minimum,
these older sets will some new electrolytic caps, and new heat-sink to
the chassis thermal grease ( if the builder put it in at all! ) and
tightening of the ground leads, but their sound is detailed, slightly
bass heavy, and in general, very good.

Later Stereo 120's notably with better green fiber circuit boards are
sonically ruined with tantalum input caps; TIP Mod Plastic driver
transistors, and minor circuit changes to prevent the TIP Parts and
2N3772 Output Transistors from self-destructing in oscillation to the
detriment of the sound. These are usually the worst sounding
Stereo-120 units.

My own Bender-Stereo 120.ULT Level 3A Rebuild Amplifier Kit which uses
my proprietary ULT output transistors, replaces most of the resistors,
caps, and transistors in the set, bringing the amp 30 years later into
the 21st century, to a better than Krell/Levinson/Cello Sonic, and the
"Reviews" on my website speak for themselves, as I did not write any
of them.

--
Steven L. Bender, Designer of Vintage Audio Equipment


See my Bender Amplifier Rebuild Kit Pages:

http://slbender.netfirms.com
or
http://slbender.exactpages.com


My Vintage Akai Reel to Reel Photo Pages:

http://slbender.netfirms.com/akai.html
or
http://slbender.exactpages.com/akai.html


The updated Akai Reel to Reel Dates & Details Page:

http://slbender.netfirms.com/akaidt.html
or
http://slbender.exactpages.com/akaidt.html


Support: The Alternative Breast Cancer Research ( ABCR ) Project

http://abcr.netfirms.com
or
http://abcr.exactpages.com



"Lars Brandt" wrote in message ...
Thank you for all the comments. I have got a some inputs:
That todays IC stereo amplifier is at least as good as 1970s Dynaco (PAT-4,
ST-120).
But when I heard this Dynaco home at a friend 1974 I think it sounds better
than even a Marantz reciever,better than everything I have listened to.
Regards
Lars