Hello!
I need some good circuits (PCB) which based on 2N3055... How much power is possible to get with these? 😕
I need some good circuits (PCB) which based on 2N3055... How much power is possible to get with these? 😕
Hi,
This is a very old device. I used to use these for audio in the late 60's.
Although they appear to have a high Ptot, this is for a water cooled heatsink, and most samples available could never reach this even then.
There are some designs dating from the 70's that use them, including the Quad 303. (Or it used an equivalent).
One that I made at that time was this:
http://sound.westhost.com/jll_hood.htm
Not much power, but it sounded better than the Quad.
Unless you have a zero budget, I would suggest looking at some more modern devices.
Cheers,
This is a very old device. I used to use these for audio in the late 60's.
Although they appear to have a high Ptot, this is for a water cooled heatsink, and most samples available could never reach this even then.
There are some designs dating from the 70's that use them, including the Quad 303. (Or it used an equivalent).
One that I made at that time was this:
http://sound.westhost.com/jll_hood.htm
Not much power, but it sounded better than the Quad.
Unless you have a zero budget, I would suggest looking at some more modern devices.
Cheers,
2N3055
Hello macgyver
John Linsley-Hood’s 15W Class-A power amp which based on 2N3055
Hi, go to
http://www.gmweb.btinternet.co.uk/jlh1996.htm

Hello macgyver
John Linsley-Hood’s 15W Class-A power amp which based on 2N3055
Hi, go to
http://www.gmweb.btinternet.co.uk/jlh1996.htm

Re: 2N3055
Here is a Thread about 2N3055 amplifier
with schematics.
2N3055 amplifier - thread
Have you Searched here
at diyaudio?
2N3055 is such a usual transistor, that very many amplifiers
have used this as Output devices.
/halo - now searching the web for some more - with PCB
#######################################################
Here is the results, 12 hits
for search:
Google: "power amplifier" 2N3055 PCB schematics
nickgreek said:Hello macgyver
John Linsley-Hood’s 15W Class-A power amp which based on 2N3055
Hi, go to
http://www.gmweb.btinternet.co.uk/jlh1996.htm
![]()
Here is a Thread about 2N3055 amplifier
with schematics.
2N3055 amplifier - thread
Have you Searched here
at diyaudio?
2N3055 is such a usual transistor, that very many amplifiers
have used this as Output devices.
/halo - now searching the web for some more - with PCB
#######################################################
Here is the results, 12 hits
for search:
Google: "power amplifier" 2N3055 PCB schematics
Another classic design based on the 2n3055 was the
Dynaco St-120. On a good day it could do 60 watts/ch
but usally about 55 watts/ch.
The sound is unique and is one of the simpliest designs of a
power amplifier.
The schematic/PCB is located at -
http://home.indy.net/~gregdunn/dynaco/components/ST120
🙂
Dynaco St-120. On a good day it could do 60 watts/ch
but usally about 55 watts/ch.
The sound is unique and is one of the simpliest designs of a
power amplifier.
The schematic/PCB is located at -
http://home.indy.net/~gregdunn/dynaco/components/ST120
🙂
A Good Old Dynaco ST120
that was a Good Oldie Amp! 😉
and simple and easy to build, too
##########################################################
I recommend a visit at Ted's Website!
Ted's World of Power Amplification - Schematics & Schematics and ....
##########################################################
I like that
/halo - has got one more schematic
Thanks, tedted said:Another classic design based on the 2n3055 was the
Dynaco St-120. On a good day it could do 60 watts/ch
but usally about 55 watts/ch.
The sound is unique and is one of the simpliest designs of a
power amplifier.
The schematic/PCB is located at -
http://home.indy.net/~gregdunn/dynaco/components/ST120
🙂
that was a Good Oldie Amp! 😉
and simple and easy to build, too
##########################################################
I recommend a visit at Ted's Website!
Ted's World of Power Amplification - Schematics & Schematics and ....
##########################################################
I like that
/halo - has got one more schematic

Let's not remember the NAD 3020. It also used 2N3055s. If you heat sink them really well, you can probably get 40-50 watts in an AB output amp, maybe more. But you can find devices today that are more linear with higher BETA at high currents that will likely result in a better sound that is more tolerant of the overall topology.
Alvaius
Alvaius
AFAIK, the ST-120 doesn't have a 3055 anywhere in it...Another classic design based on the 2n3055 was the
Dynaco St-120. On a good day it could do 60 watts/ch
but usally about 55 watts/ch.
But the ST-80 does (40W/Ch).
www4.ncsu.edu/~jdchmiel/amp.zip
this is a zip of all the info that came with A Qkits amplifier kit I got once ampon a time that seems to be discontinued now. Anyways, it is rates 100x1@8ohm or 175x1@4ohm and i verified it at smoke X lots @ 2ohm. I am going to replce the fried 3055's with MJ15003's as it was reccomended to me on this board as being a better all around transistor. This schematic and parts list might help you get started tho..
this is a zip of all the info that came with A Qkits amplifier kit I got once ampon a time that seems to be discontinued now. Anyways, it is rates 100x1@8ohm or 175x1@4ohm and i verified it at smoke X lots @ 2ohm. I am going to replce the fried 3055's with MJ15003's as it was reccomended to me on this board as being a better all around transistor. This schematic and parts list might help you get started tho..
ST-120 has 2n3055 (Really)
On many versions of the ST-120 that were kit built, the output's were indeed 2n3055. Reviewing the parts list of my ST-120 Q5/Q6 were 2N3055 Dynaco Part # 571844. (Serial number 17828060).
Another test to see what version you have, look at Q3/Q4 (drivers). If they are 2n3053/2n4037 and NOT the TIP's, then you have a older kit version of the ST-120 that has not been modified.
On later models they did switch to a better output/drivers.
The reason a 2N3055 works is due to the regulated 72V power-supply. That's right the ST-120 actually had a regulated supply.
You may ask, but wait the 2N3055 has too low a Vceo. That is true but it does have a Vcer of 70 volts and a Vcb of 100V. Thus allowing a 2N3055 to just squeek in, assuming a little power supply droop.
The regulated supply is what I feel gives this amplifier it's unique sound even with slow outdated outputs such as 2N3055's.
🙂
On many versions of the ST-120 that were kit built, the output's were indeed 2n3055. Reviewing the parts list of my ST-120 Q5/Q6 were 2N3055 Dynaco Part # 571844. (Serial number 17828060).
Another test to see what version you have, look at Q3/Q4 (drivers). If they are 2n3053/2n4037 and NOT the TIP's, then you have a older kit version of the ST-120 that has not been modified.
On later models they did switch to a better output/drivers.
The reason a 2N3055 works is due to the regulated 72V power-supply. That's right the ST-120 actually had a regulated supply.
You may ask, but wait the 2N3055 has too low a Vceo. That is true but it does have a Vcer of 70 volts and a Vcb of 100V. Thus allowing a 2N3055 to just squeek in, assuming a little power supply droop.
The regulated supply is what I feel gives this amplifier it's unique sound even with slow outdated outputs such as 2N3055's.
🙂
Elliots Project 12 - El Cheapo Improved Amp
Rod Elliots Project 12 - El Cheapo Improved Amp
This amplifier is with cheap and easy to find components
is an improved version of an old 2N3055 amp.
El-Cheapo - A Really Simple Power Amplifier
---------------------------------------------
😉 Figure 3 - The "Even-Newer More-Improved" El-Cheapo 😉
/halo
Rod Elliots Project 12 - El Cheapo Improved Amp
This amplifier is with cheap and easy to find components
is an improved version of an old 2N3055 amp.
El-Cheapo - A Really Simple Power Amplifier
---------------------------------------------
😉 Figure 3 - The "Even-Newer More-Improved" El-Cheapo 😉
/halo
Attachments
At least this kinda crap has bypass c's
The 2N3055 has been around for over 30 years, do I hear innovation... come on.
crabby old guy building a tube pre amp
(its all a joke)
The 2N3055 has been around for over 30 years, do I hear innovation... come on.
crabby old guy building a tube pre amp
(its all a joke)
Well, for what it's worth, I just switched an ESP3A amp from 2N3055/MJ2955 to the MJ15003/15004. There was a significant difference. It sounded pretty good before, but sounded far better afterwards.
I have some spare old 2N3055s if you wanna drop by to pick 'em up...
I have some spare old 2N3055s if you wanna drop by to pick 'em up...
Re: ST-120 has 2n3055 (Really)
Live & learn.
Hmmm..I didn't know that. All the 120's I'd seen had the 3772's.ted said:On many versions of the ST-120 that were kit built, the output's were indeed 2n3055. Reviewing the parts list of my ST-120 Q5/Q6 were 2N3055 Dynaco Part # 571844. (Serial number 17828060).
Another test to see what version you have, look at Q3/Q4 (drivers). If they are 2n3053/2n4037 and NOT the TIP's, then you have a older kit version of the ST-120 that has not been modified.
On later models they did switch to a better output/drivers.
Live & learn.
Phase Linear ( i.e. Bob Carver ) used a whole bunch of 2N3055's in the 400 series IIRC ( about 6 or 8 per channel ) to deliver 200 Watts....
Ray
nostalgia aint what it used to be....
Ray
nostalgia aint what it used to be....
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