Magnum IA120 Integrated information

[P.Allan.]

Hi i recently purchased one of the above amplifiers in working condition off trade me but would like to know more about the company ect or even get some service info schematics ect.
judging by the date codes on the devices i would say the amp was manufactured about the middle nineties but have been unable to find any information on the net any help would be greatly apreciated.
Thanks Peter.

 

[P.Allan.]

I have spent some time working out the schematic for this amp and will post it for any one else who may be interested if i am allowed to do so.
However the audition of this amp was rather dissapointing and as i bought it cheaply i will probably use the case transformer and better quality parts to build something new.
Does any one have any suggestions for an AB design of arround 50-60W?
Regards to all.

 

[Zen Mod]

line stage is basically LTP with buffer ;
rest is MC stage with small bjts , few OPs as supply reg for MC stage , two SIP OPs for MM stage , rec buffer OP

power amp is slightly tweaked Hitachi schematic from their Application notes , but with typical Olde England diminutive Iq .

if you're interested - I can post schematic ( power stage is floating already somewhere on DiyA ) , for preamp I need to scan ......

recommendation - leave it as is - you can hardly squeeze anything better sounding in that case/heatsink

or - remove entirely preamp pcb , make decent input selector and attenuator and use just power amp as integrated .

I'm writing all this presuming that your IA120 is similar to IA125 , which I owned somewhere in the past

 

[P.Allan.]

This amp seems somewhat different to the model you describe i would be interested in the schematics you have and would gladly send you a PDF of my schematic if you wish to compare them.

 

[P.Allan.]

here is an internal picture of the amp

 

[Zen Mod]

huh - that's surprise ..... completely different ....

anyway - this is schematic of IA125 , output section

 

[P.Allan.]

here is the schematic for those who may be interested

 

[voltarin]

Thanks, it´s very usefull to me.

 

[Lamvi62]

Magnum IA120

Hello, I just walked in your community for a problem to my Magnum IA120 amplifier, the mine has a different scheme and the chipset broken, you can know the name of this chip because I can not read the letters. Thank you
vincenzo
P.S. I can not insert a photo of the interior of the amp
https://www.facebook.com/photo.php?fbid=10208300745543595&set=p.10208300745543595&type=3&theater

 

[Lamvi62]

https://www.facebook.com/photo.php?fbid=10208300745543595&set=p.10208300745543595&type=3&theater

 

[herbie333]

Hi,


i'm repairing a MAGNUM IA120.


One channel is working, the second has a DC offset of -44 V. Surprisingly the loudspeaker relais is on.
Many of the components are broken or burned, so that i cannot change it.


First I was happy that I found here a circuit, but i am not able to read the component values.


Have anyone the circuit diagram with a better quality?


Greetings from Austria,
Herbert