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Commercial IC power amps used by vendors

Started by ponchojuan, August 26, 2009, 09:28:21 AM

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ponchojuan

I started this thread to to create a central point for understanding what the major vendors are using for their power amp section in their product lines.  I think there is a lot to be learned from their designs as well as track records for reliability and performance.

Many vendors are now using power IC audio amps with good results.  If you have information to share based on your own newer amps or experience under the hood, please share.  Please keep conjecture, hypothication, and SWAG to yourself. "Just the facts Mam".

Poncho

ponchojuan

It appears the MG series of Marshall amps is using the TDA7293.  The IC appears to be used in both the MG50DFX as well as the MG100DFX.  Here are the schematics.  I have the 100W and like the sound and projection.  Seems pretty rugged and does not put out that much heat.

http://www.ampix.org/albums/userpics/10003/Marshall_MG50dfx.pdf

http://www.ampix.org/albums/userpics/10003/MArshall_MG100DFX.pdf

I will have the 100W apart this weekend and will snap some pics to share.

Poncho

teemuk

#2
Marshall commonly uses the TDA7293 chips in the high power amps, not only in MG series. Marshall also has used TDA and LM series chips.

Carlsbro and AER use TDA7293/7294 chips as well.

Crate uses TDA series chips in their low powered amps.

Vox uses TDA series chips or LM3886.

Line 6 uses TDA series chips or LM3886.

Tech 21 uses LM3876 in the Trademark 60 and Power Engine.

Aguilar uses Tripath chips to control the output's switching MOSFETs.

New low power Kustom amps use TDA series chips.

Peavey has used LM series of chips.

Fender has commonly used TDA series chips.

Roland uses LM3886 at least in the new Cube 60 amp.


...Basically, I think they just pick what fits the application.

joecool85

Wow, I know the LM3886 works great for guitar oriented power amps, but didn't realize it was used commercial - and quite frequently no less!

Also, my Dean Markley K-20X uses a TDA2030.  I love the sound and output of it, it's pretty much the best practice amp I could ask for.  I do wish it had reverb though...
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

J M Fahey

I'd like to add TDA1514 used in 40W Marshalls and uPC1188 used in around 25W Fenders .
I´m drawing my simplified TDA7294 boards to use them in the close future.
I'll post results when tested "on the road".

dsmnoisemaker

i couldn´t find a difference between the MG50DFX and the MG100DFX schems you posted..
i don´t think that the MG100DFX uses only 1 TDA2394..maybe 2 in BTL mode?

by the way i noticed that the power capacitors were only 1000uF?? isn´t that too small?

mensur

Quote from: dsmnoisemaker on August 31, 2009, 10:06:07 PM
i couldn´t find a difference between the MG50DFX and the MG100DFX schems you posted..
i don´t think that the MG100DFX uses only 1 TDA2394..maybe 2 in BTL mode?

by the way i noticed that the power capacitors were only 1000uF?? isn´t that too small?
The difference between MG50/100 are in power supply (smaller mains transformer, couple of volts lower supply on MG50).
1000uF caps are correct values, thats a neat trick to emulate sag effect of tube power output.

dsmnoisemaker

haha, i mess with the chip number.. i meant TDA7293..
but still mensur, according to the datasheet, its maximum power is 100w at 4 ohms @ +-30v, but this thing has a fairly complicated current feedback ckt so its power sould be lower..

also, at 100W the THD is 10%..yikes!