2n3055

[Ford_V6]

Hy

Waht amp can be built with 2N3055 transistors ? Here in romania they are extremly cheap. About 0.3 $

 

[Jeff R]

The 2N3055 is an old, rather generic transistor. Many amps can use it - just keep them within their voltage and current (and power) specifications.

 

[paulb]

Two designs that come to mind. Both recommend upgrading from 2N3055s to get better sound.

ESP P3A at www.sound.au.com

JLH Class A at www.gmweb.btinternet.co.uk

 

[argo]

Two designs that come to mind. Both recommend upgrading from 2N3055s to get better sound.

ESP P3A at www.sound.au.com

JLH Class A at www.gmweb.btinternet.co.uk

There are 2N3055-s and 2N3055-s. Depends from manufacturer IMO. Older original Motorola devices tend to sound much better than STmicrodynamics current production. ST had more inferior sound compared to Motoralas in my JLH Class A amp. MJ15003 is said to be far better than 2N3055 though.

 

[peranders]

Waht amp can be built with 2N3055 transistors ? Here in romania they are extremly cheap. About 0.3 $

Mr Car, I think you should start in the other end. Which output transistors can I efford? The big cost is case (maybe), smoothing caps (maybe) transformers (maybe).

I think to start with "this is really cheap", is not right if you look at the whole concept. Why put much work into an amp with crappy output transistors?

 

[Ford_V6]

I was just asking, i'am not planing to use them.

 

[Dj BASS AMP]

O L D !

 

[djk]

"Why put much work into an amp with crappy output transistors?"

While I agree with this in principle, I'd like to make a couple of points.

One of the best amplifiers I have ever heard is an all NPN design using outputs with an Ft of only 0.8Mhz, design does have something to do with the sound too.

Here is a design that can use 3055s and put out 100W/8R, notice that with a couple of small changes it could be an X amp feedback arrangement.

http://home.kimo.com.tw/skychutw/Circuits/Hadley622.pdf

 

[Diode]

3055's may not be suited for output transistors but make very good powersupply pass transistors for a high current regulated supply! If you are going to regulate your supply, use the 3055's unless a huge voltage will be used!!!! If maybe a friend gave you a bag of them for free and you want to use them, match them very closely. They will work. I'd use them in a subwoofer amp if so.....

Good luck.

 

[JojoD818]

3055s

Hi,

I've used 3055s since they are also cheap here in my country. Though sound is not a case when I used them. All I need was power and lots of power so I used a bunch of them.

I'll try posting the schematic asap.

JojoD

 

[red]

Hello to all!!
I have an answer to Ford_v6.Sorry for the inconvinient but it will be in Romanian.I'm not swering.Cross my heart.
Este mai simplu sa investesti intr-o pereche de Mj -uri decat sa folosesti 2n3055.Eu am folosit multe pt. amplificatoare si sunt o adevarata catastrofa...Sunt proaste,se ard repede si nu au viteza de reactie destul de mare.Intradevar obtii puteri mari dar numai pe medii pentru ca pe bas iti misca difuzorul dar nu il auzi...Asta e!!Stiu ca sunt ieftine si se pot inlocui usor dar daca faci un amplificator pe niste tranzistoare bune,il reglezi cum trebuie si nu iesi niciodata din parametrii lui de functionare nu il poti arde!!
Daca totusi vrei sa faci ceva puternic pe 2n3055 iti sugerez sa pui mai multe in paralel ca sa nu se incalzeasca.

 

[sayang001]

You could use the 2N3055 and 2N2905 in this design as well:

http://vanleusden.xs4all.nl/popeye/popeye_power_amp.pdf

But you would have to lower the supplyvoltages to +40V / -40V
the 2N3055 and 2N2905 cannot handle the higher voltages.

 

[Ford_V6]

Thanks red, but i was only asking. I'am not planning to use them. I use TIP transistors for now.

P.S. Ma bucur sa mai vad un roman pe forum.

 

[stefanbujor]

I've made an amplifier using 2N3055 (the ETI 480) which delivers arround 65 - 70W / 4ohm from a 33V suply.
I had lying around some old 2N3055 and I bought only 2 MJ2955 (for the final stage).
Verdict?
The MJ2955 were counterfeit and burned at arround 20W RMS, and also a lot of parts on my amplifier as well
The majority of 2N3055 available on the Romanian market are counterfeit, and that's why they don't sound veryy well and they don't handle more than 40W.
I made my amp (ETI 480) using some old (but gold ) 2N3055 and I'm very pleased of the way that it sounds.
Any of you, Ford or red know where I can get some real MJ15003?
Or some other power transitors (audio intended) that you bought and used in your amplifiers.

 

[Hornlover]

The 2N3055 can sound just fine. Just because it is old doesnt mean its not capable. A lot of factors can have an effect on the sound quality. You can always replace them at a later time if you desire to, if a better device becomes available. Use them, and dont worry about it.

 

[Lisandro_P]

The 2N3055/2955 are very capable power transistors for audio. Of course, there're better choices (more linear, less noisy, with better power handling), but that doesn't mean an amp built with such transistors will sound like crap.

My JLH '96 currently uses 2N3055 and sounds like a dream.

 

[mandat]

The old 2N3055 transistors have got FT about 800 kHz but actually produced transistors have got 4 MHz and you know where the reason is.

 

[destroyer X]

2N3055 is alike husband and wife, everybody say that is awfull, but they have one

At least they have one.

2N3773, 2N3772, 2N3771 are better.... and many BDY too.

All modern transistors do a better job.

But the JLH i assembled with new transistors...aaaaaghhh! bad sound they made, do not asked my why!...i cannot answer you...non sense?... i also think so.

here one explendid class A schematic.

regards,

Carlos

 

[Jonathan Bright]

Just a slight word of caution. The circuit that destroyer X just posted was origianlly published with one small mistake. It is the JLH from 1996 and the cap (C4) in the lower fb arm should go to earth and not to the -ive power supply rail. This is a very good place to start using all your old 2n3055's. A very extensive discussion of this design can be found at Geoff Moss's site which is referred to frequently in the "JLH 10watt class A" thread.

 

[destroyer X]

Jonathan, thank you, the position of C4 is really wrong.

Must connect it to earth.

thanks,

Carlos