Has Anyone else used MJE13005's Switching Transistors for the output stage.

[John Biles]

Hello Everyone,
my local parts store lists MJE13005 8A NPN Switching Transistors in their Catalog.
as they were $1.78 each i thought i'd try them in My B Class Amplifier as i use a quasi-complimentary output stage using NPN's.
This Transistor is used mainly in Motor Switching circuits.

If you do a web search it is easy to find a data sheet.

i have been using them in my test amp for a few months with no problems.
I started with 2N3055's amd latter changed over to MJE15003's and to me the MJE13005's sound just as good or slighty better than the MJE15003's.
I normally Pay around $7.00 for MJE15003's

 

[destroyer X]

I have used TIP142 and TIP147 as output darlington transistors

I think they distorted the trebles.

And i could read, in our forum, that they are not adequated, as we cannot adjust the internal emitter driver resistor.

Really made for switching purposes.

Treble distortion was boering.... really strange harshing, scratching sound....

The bass was very nice and deep, but a little unprecise too.... but the bass quality was more the amplifier fault than the darlington unit fault.

regards,

Carlos

 

[MikeB]

Hi !
You should be careful with switchingtransistors, typically they are
constructed for switching and can dissipate much power for only
very short time. Take a look to SOA diagrams...
(I guess you meant mj15003 ?)

Mike

 

[tlf9999]

I think you will just be fine.

I have used TIP's in linear applications without any trouble. I have used IRF devices (designed exclusively for switching) in audio applications very successfully.

Transistors are transistors.

 

[jackinnj]

I have used the MJE13005 in a switcher with the MC34166 controller and they worked quite well. I have a huge bunch leftover if anyone cares.

 

[Enzo]

"Transistors are transistors" is a bit flippant and not very accurate. There is a big space between get away with and should have. Transistors are not all made the same nor designed to be universal. One would not say cars are cars - all share similarities but a Honda Civic is not a unlimited class dragster nor is it an offroad like a jeep or Hummer. That Honda won't be very happy pulling a large travel trailer over the mountains, even if you do get away with it. Likewise the dragster is not a good choice for driving to the grocery store. The DC ratings on the switching transistors tend to be much lower than the ratings for switchmode applications.

WHy did you select the MJE13005 by the way? It would seem the 2N3055A would be better for you. Just for sake of discussion I assumed 30v rails, so +/-30VDC. That means potentailly 60v across the part. At those voltages the MJE13005 is rated less than an amp while the 2N3055A still has a 2 amp rating. The MJE13005 is only a 75 watt part, while the 2N3055A is good for 115 watts. Of course if you are just using it for a low power amp, then none of that matters much.

And I am not sure about MJE15003. Did you mean MJ15003 or MJE15030? I don't find MJE15003. The MJE15030 is a TO220 like the MJE13005.

 

[John Biles]

Hello Everyone,
Here's the datasheet for MJE13005

 

[tlf9999]

[BTransistors are not all made the same nor designed to be universal. [/B]

Absolutely true.

One would not say cars are cars - all share similarities but a Honda Civic is not a unlimited class dragster nor is it an offroad like a jeep or Hummer. [/B]

That's a valid argument if you can show that this application is either drag racing or offroading, not driving the kids to the park?

 

[N-Channel]

MJE13005 Datasheet

try this datasheet from OnSemi. A little better picture here:


http://www.onsemi.com/pub/Collateral/MJE13005-D.PDF

Best regards,

Steve

 

[djk]

For a switching transistor the MJE13005 has good SOA up to 50V or so. It is intended for 220V off line switching where it can control a couple of hundred watts.

The Beta drops like a rock above 1A, not something I would use.

An MJ15015 is used in the Carver M400T and the Crown Power Base 1, both 200W amplifiers. I pay USD$1.23 for mine. 180W SOA at 60V with good Beta out to 5A, 120V CE ratings.

 

[John Biles]

Here's a picture of my B Class Amplifier Using MJE13005 NPN Switching Transistors.

 

[Fritzell]

Sweet

Btw the 2N3055 isn't very linear and are often disregarded as bad for audio but if youre building a smallpower (~50W) poweramp you could parallell two 3055 since those are pretty cheap and reduce Large Signal noise and THD

 

[tlf9999]

John, how does it sound?

 

[John Biles]

It's Sounds fine, I've originally had the good old 2N3055's for the output then I changed them for MJE15003's and there wasn't a great difference.
Then i saw these (MJE13005's) in the local electronic store and downloaded the datasheet and decided to give them a go and i've been using them in my Amplifier for months with no problems.
I have all 3 different types of transistors mentioned on small heats, so it only takes me about 5 minutes to change them over.
I normally play the same song or group of songs when running tests with each new output transistor I try.
A it has been a couple of months since i ran tests to hear how much difference there is between the 3 different transistors, i think i will run some long tests and find out for myself which transistor sounds best.
I will most likely look for come other transistors to try on the output before I decide what will be used for the finally circuit.
Any Ideas?

 

[Fritzell]

The 2SC3281/2SA1302 are said to be very linear and has a good name in Hifi industry

 

[MikeB]

For TO3 you should try the MJ15024/25, seems to be a very good transistor.
I can't recommend the 2SC3281/2SA1302, they are no longer in
production and you will get fakes if you try to buy these.
I really like the Onsemi versions, the MJL3281/1302, these are still
in production and are widely used.

Mike

 

[Fritzell]

Aha sorry didn't saw that. The MJL are the motorola versions

 

[usekgb]

For TO3 you should try the MJ15024/25, seems to be a very good transistor.
I can't recommend the 2SC3281/2SA1302, they are no longer in
production and you will get fakes if you try to buy these.
I really like the Onsemi versions, the MJL3281/1302, these are still
in production and are widely used.

Mike

I've got piles of the 2SC3281/2SA1302's from repairing JBL EON's. One of these days, I'll get around to doing something with them.

Cheers,
Zach

 

[John Biles]

Hello Fritzell, you say that Paralleling output transistors reduce distortion and noise, I have read that before, have you heard or measured this yourself, was there a big difference?

 

[Fritzell]

Hey, i didn't measure this myself but it is discussed in Power Amplifier Design Handbook. The distorsion/noise is said to be halved because when you load a transistor with high Ic, Hfe will get lower