MOSFET replacement queston. K135 and J50 with BUZ900/BUZ905 vs BUZ901/BUZ906
Hi all,
I have some noise issues in my amp and I would like to replace the mosfets. I already have a thread running about the amp here but I want to know what are my options for the MOSFETS.
I have already dug around but I want to make sure there is not something I am missing.
The originals are: K135 and J50 MOSFETS
People recommend:
BUZ900 & BUZ905 as the exact replacements at $10 each ;( for $120 total from Newark
or I found the
BUZ901 & BUZ906 as alternative replacements at $8 each
for $96 total from Newark
I also found the BUZ900 & BUZ905 on eBay from a Chinese seller for $5 each
BUZ900 Manu IR Encapsulation TO 3 N Channel Power Mosfet | eBay
BUZ905 Manu IR Encapsulation TO 3 NEW Product Under Development | eBay
The parts from China will cost me about $70 with shipping but will take forever to come and I am not sure if they are legit :/
I compared the specs on the BUZ900/BUZ905 vs BUZ901/BUZ906 and the only difference is the Vds respectively being 160V,-160V and 200V,-200V. The Hitachi MOSFETs are rated at Vds 160V and -160V. They also share the same datasheets!
For me it is a clear choise to go with the cheaper and better Vds MOSFET set of BUZ901, BUZ906. What do you guys think? Is it going to screw things up?
Thanks!
Hi all,
I have some noise issues in my amp and I would like to replace the mosfets. I already have a thread running about the amp here but I want to know what are my options for the MOSFETS.
I have already dug around but I want to make sure there is not something I am missing.
The originals are: K135 and J50 MOSFETS
People recommend:
BUZ900 & BUZ905 as the exact replacements at $10 each ;( for $120 total from Newark
or I found the
BUZ901 & BUZ906 as alternative replacements at $8 each
I also found the BUZ900 & BUZ905 on eBay from a Chinese seller for $5 each
BUZ900 Manu IR Encapsulation TO 3 N Channel Power Mosfet | eBay
BUZ905 Manu IR Encapsulation TO 3 NEW Product Under Development | eBay
The parts from China will cost me about $70 with shipping but will take forever to come and I am not sure if they are legit :/
I compared the specs on the BUZ900/BUZ905 vs BUZ901/BUZ906 and the only difference is the Vds respectively being 160V,-160V and 200V,-200V. The Hitachi MOSFETs are rated at Vds 160V and -160V. They also share the same datasheets!
For me it is a clear choise to go with the cheaper and better Vds MOSFET set of BUZ901, BUZ906. What do you guys think? Is it going to screw things up?
Thanks!
The output devices have little to with noise in amplifiers.
Since they can last a lifetime, I see quite a few amps still fitted with these original parts from around 1980. The amplifier may have noise problems due to other failures like electrolytic capacitors, corrosion, solder joints, rough handling etc. but not heard of a need to take your solution yet.
Still, If you just want some shiny new output MOSFETs, fine.
Since they can last a lifetime, I see quite a few amps still fitted with these original parts from around 1980. The amplifier may have noise problems due to other failures like electrolytic capacitors, corrosion, solder joints, rough handling etc. but not heard of a need to take your solution yet.
Still, If you just want some shiny new output MOSFETs, fine.
you are walking a wrong path and as far as i can tell you have been told more than once ...
Since you seem to manage with electronics , then since it seems that you have plenty of money to spend do this ...
remove one of the modules , operate it with a generic power supply outside the construction to see how it will behave outside the box . I expect it if it doesn't have any damage to be dead quiet .
The things i may tell only from the pictures you posted is that you have mechanical problems that have a lot to do with how your trafo is made and mounted ( its not factory made it seems to me that its costume made )
Obviously you have also some wiring issues computer cables is the worst as flat cables when it comes to audio signals ( if audio is traveling inside mixed with other signals )
Since you seem to manage with electronics , then since it seems that you have plenty of money to spend do this ...
remove one of the modules , operate it with a generic power supply outside the construction to see how it will behave outside the box . I expect it if it doesn't have any damage to be dead quiet .
The things i may tell only from the pictures you posted is that you have mechanical problems that have a lot to do with how your trafo is made and mounted ( its not factory made it seems to me that its costume made )
Obviously you have also some wiring issues computer cables is the worst as flat cables when it comes to audio signals ( if audio is traveling inside mixed with other signals )
Thanks for the suggestions guys. It is a lot of $$ but it is just frustrating. It is good to know that replacement parts are available of I need to replace them.
I have reconnected and cleaned all the contacts/screw in wires.
The trafo does hum by itself when disconnected from the circuit :/
One channel has more noise than the other.
What I will do first is reflow all the solder joints.
Than I will see if I can get a DC Power Supply from somewhere and hook up the module to it.
And I hope that will narrow it down to the Transofrmer or something else (mosfets?)
I have reconnected and cleaned all the contacts/screw in wires.
The trafo does hum by itself when disconnected from the circuit :/
One channel has more noise than the other.
What I will do first is reflow all the solder joints.
Than I will see if I can get a DC Power Supply from somewhere and hook up the module to it.
And I hope that will narrow it down to the Transofrmer or something else (mosfets?)
K135 / J50 are VERY reliable.
They will normally either work or not work. However they can sometimes fail in other ways. This will normally be show as either rail voltage across the output terminals or early clipping in the amplifier.
If the amplifier is working you are looking in the wrong area for the cause of your noise.
I would begin by chacking the output to see if you have any dc volts accross the output terminals. If you have track along the feedback path to find the cause.
Don
They will normally either work or not work. However they can sometimes fail in other ways. This will normally be show as either rail voltage across the output terminals or early clipping in the amplifier.
If the amplifier is working you are looking in the wrong area for the cause of your noise.
I would begin by chacking the output to see if you have any dc volts accross the output terminals. If you have track along the feedback path to find the cause.
Don
I just re-flowed one of the PCBs and no change.
I checked the DC voltages at the output with a multimeter and an oscilloscope. The channel I've been doing work (right) on is -30mVDC and the left is +4mVDC.
Next week I will see if I can plug in a bench-top lab power supply for the rails... and if that changes anything.
I checked the DC voltages at the output with a multimeter and an oscilloscope. The channel I've been doing work (right) on is -30mVDC and the left is +4mVDC.
Next week I will see if I can plug in a bench-top lab power supply for the rails... and if that changes anything.
if you guys don't mind we can discuss the troubleshooting in the thread below and leave this thread for replacement identification for the K135 and J50 MOSFETS
http://www.diyaudio.com/forums/soli...use-model-100-hum-buzz-troubleshooting-2.html
Others and myself would appreciate your input.
http://www.diyaudio.com/forums/soli...use-model-100-hum-buzz-troubleshooting-2.html
Others and myself would appreciate your input.
"Don't think about fakes in China"
My experience of Chinese transistors has been bad.
Bought some irfp240's and they lasted 10 minutes.
Breakdown voltage is far too low.
So any spikes on power lines will blow them.
Replaced them with some from RS Components and still going a year on !
If your amp is old I would be looking at electrolytics dying of old age first.
Check bias too.
My experience of Chinese transistors has been bad.
Bought some irfp240's and they lasted 10 minutes.
Breakdown voltage is far too low.
So any spikes on power lines will blow them.
Replaced them with some from RS Components and still going a year on !
If your amp is old I would be looking at electrolytics dying of old age first.
Check bias too.
Hello,
ECX10N and ECX10P are the similar to K135 J70 isn't it ?
Lateral MOSFETs (Buy Online) | Profusion
ECX10N and ECX10P are the similar to K135 J70 isn't it ?
Lateral MOSFETs (Buy Online) | Profusion
As always, you get what you pay for. Anyway, the overwhelming majority of Chinese products, including electronic components, is offered for suspiciously little money. In addition, failures of Chinese products/components are reported frequently. So, why shouldn't all of us be very careful?
Best regards!
In my experience the parts faked the most have been MOSFETs. Not power devices but humble SOT-23s. Fakes are normally easy to spot because the threshold voltage differs from the DS. The most recent example I have is RYC002N05 - this seems rather unique in the world of MOSFETs as its threshold is the lowest I've ever seen in a MOSFET - about equal to a bipolar transistor. The fakes I was sent by a couple of Taobao sellers were different from each other and had nowhere near the Vth of this device.
Eventually had to turn to a HK supplier to get the real thing which I verified by checking the Vth.
RYC002N05 - 0.9V Drive Nch MOSFET | ROHM Semiconductor - ROHM Co., Ltd.
Eventually had to turn to a HK supplier to get the real thing which I verified by checking the Vth.
RYC002N05 - 0.9V Drive Nch MOSFET | ROHM Semiconductor - ROHM Co., Ltd.
I'm concidering building the Cordell version of the Hafler, and have enough of both 2SK/SJ and BUZ to build the amp, but one type has to serve as potential spares for the other....
Irregardless of price and availability - is the BUZ series and 2 SJ/SK 35/150 sufficiently equivalent to be interchangable??
Irregardless of price and availability - is the BUZ series and 2 SJ/SK 35/150 sufficiently equivalent to be interchangable??
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The numbering of these lateral mosfet substitutes has long been a confusing issue. I believe from previous threads on this same topic, that whether they are labelled in the Renesas 2SK and 2SJ series, Semelab's BUZ series, Alfet ALF series or Profusion's ECF/ECX Exicon series, the different numbers are really only about marketing. Pick the appropriate package and comparable datasheets and see that they fall into the same groups for yourself. Note that there are differently specified power ratings for the defunct ALFET brand - more marketing reasons, I suspect.
Yes, Lateral mosfets being principally audio components, the details and marketing are sometimes smoke and mirrors. For some years now, the only current lateral audio mosfet power product has been single or double-die versions of the same original 2SK1058/J162 and 2SK 150/2SJ35 Hitachi/Renesas types. Anyways, I'm confident that you'll have little problem using genuine BUZ900 series semis in lieu of the similar package and rated types. To be on the safe side, there may be assembly differences, so I'd keep the brands consistent for each pair or set of pairs as necessary for Hafler designs. For the sake of repetition, don't even think of online Chinese sources. Choose a real, bricks and mortar type distibution business with tech support and a dependence on reliability to stay in business.
Yes, Lateral mosfets being principally audio components, the details and marketing are sometimes smoke and mirrors. For some years now, the only current lateral audio mosfet power product has been single or double-die versions of the same original 2SK1058/J162 and 2SK 150/2SJ35 Hitachi/Renesas types. Anyways, I'm confident that you'll have little problem using genuine BUZ900 series semis in lieu of the similar package and rated types. To be on the safe side, there may be assembly differences, so I'd keep the brands consistent for each pair or set of pairs as necessary for Hafler designs. For the sake of repetition, don't even think of online Chinese sources. Choose a real, bricks and mortar type distibution business with tech support and a dependence on reliability to stay in business.
Bob has written a document on testing and matching Lateral Mosfets for use in the amp
http://www.cordellaudio.com/poweramp/DH-220C_MOSFET.shtmlAs said above I think the new ones are all essentially the same and do not buy from Asia, get the real McCoy
I used some Profusion "-S" matched devices in one DH-200 proto, it is the one I kept.
One early proto used a pair of Semelab dual die devices in the TO-264 mounted to an old/removed LME49830 pcb.
http://www.cordellaudio.com/poweramp/DH-220C_MOSFET.shtmlAs said above I think the new ones are all essentially the same and do not buy from Asia, get the real McCoy
I used some Profusion "-S" matched devices in one DH-200 proto, it is the one I kept.
One early proto used a pair of Semelab dual die devices in the TO-264 mounted to an old/removed LME49830 pcb.