Hello
You have to make a plan about the amplifier you want to build .
You have to know the quality of the amp before you decide ' I want to build these or that" !
If you start something and after you change your mind you probably end up with amp later you won't like it .. Waste of money..
The Mostre is great amp if carefully built .
That amp has the reputation , quality !
To give up because you don't find a part one or two day just not worth it.
There are great new parts but you have to study and do some test , research.
I had the original Hiraga Class A transistors and I sold them because I find better sounding parts ! I did tested!
Even N Pass wrote it is possible to replace those old parts with a new one . But you have to test them !
JFet available on the Ebay , Even matched set for $10 2 pair . You can use 2SK170 &2SJ74 BL , Y , GR , V grade . You have to adjust the 1K resistor to set up the right bias.
For example buy 2PC 1K trim pot , when you know the right value replace it with resistors.
I think there is no reason to give up something specially if you have the most of the parts which cost more.
Like transformer , heat sink etc .
Which amp you want to build , the Class A or the Le Monstre??
You have to have the DIY spirit , do not give up.
Also use the Net to find out the transistor complementary parts .
Do not mix the up , not enough just one PNP and another NPN!
I wrote these to encourage you , not to criticise , I have over 21 years DIY experience . I know sometimes frustrating to get the right parts but to solve the problem do not change all the amp to something else!
Greetings
You have to make a plan about the amplifier you want to build .
You have to know the quality of the amp before you decide ' I want to build these or that" !
If you start something and after you change your mind you probably end up with amp later you won't like it .. Waste of money..
The Mostre is great amp if carefully built .
That amp has the reputation , quality !
To give up because you don't find a part one or two day just not worth it.
There are great new parts but you have to study and do some test , research.
I had the original Hiraga Class A transistors and I sold them because I find better sounding parts ! I did tested!
Even N Pass wrote it is possible to replace those old parts with a new one . But you have to test them !
JFet available on the Ebay , Even matched set for $10 2 pair . You can use 2SK170 &2SJ74 BL , Y , GR , V grade . You have to adjust the 1K resistor to set up the right bias.
For example buy 2PC 1K trim pot , when you know the right value replace it with resistors.
I think there is no reason to give up something specially if you have the most of the parts which cost more.
Like transformer , heat sink etc .
Which amp you want to build , the Class A or the Le Monstre??
You have to have the DIY spirit , do not give up.
Also use the Net to find out the transistor complementary parts .
Do not mix the up , not enough just one PNP and another NPN!
I wrote these to encourage you , not to criticise , I have over 21 years DIY experience . I know sometimes frustrating to get the right parts but to solve the problem do not change all the amp to something else!
Greetings
Last edited:
Yep Sure I do understand what you say but troubled is I am a beginner at this and I see it as too much variation of transistor part numbers for this amp plus I don’t want to search the word wide for a set of transistors just for one amp
I have built a couple of things but mostly Tube Phono stage and Tube Single ended Headphone Amps so I think I will consider a F3 maybe the F4 or the JLH from Geoff’s the Class A amp website least I can get the transistors for it Easily without the confusion of different part numbers
Hi Colin,
I think you'll find what you need if you keep looking - the links gaborbela and I posted above will help, and I'm sure you can find other on the internet.
If you really think it's too much trouble then since you already have the pcb (right?) why not do the "modern equivalents" 8W version on the link I posted above? It uses BC550/560 and TIP2955/3055, which are available just about anywhere, and 2SK246/2SJ103, which you can get from
the Ambslab link above.
Cheers
Nigel
I think you'll find what you need if you keep looking - the links gaborbela and I posted above will help, and I'm sure you can find other on the internet.
If you really think it's too much trouble then since you already have the pcb (right?) why not do the "modern equivalents" 8W version on the link I posted above? It uses BC550/560 and TIP2955/3055, which are available just about anywhere, and 2SK246/2SJ103, which you can get from
the Ambslab link above.
Cheers
Nigel
Yep I have seen that version with the BC550/560 but that’s my point two many versions of the amp plus there’s a thread I have seen somewhere that saying using different transistors from the originals changes the Iimpedance of the amp from 4ohms I think It said to about 20 ohms not sure why but its drifting away from what the amp is about in my view Also the TIP2955/3055 sound a bit too dark for my taste the Quad 303 comes to mind with theses transistors you see that’s the problem that good amp can be ripped a part and cloned that there no longer the good amps you once knew
PS if I come across the correct transistors I will have a go at the amp but as I have said I do not want to surf the planet for parts that may not even work sorry but Diy Audio for me is about building not searching for obsolete parts that may not be matched or even work when to get them
PS if I come across the correct transistors I will have a go at the amp but as I have said I do not want to surf the planet for parts that may not even work sorry but Diy Audio for me is about building not searching for obsolete parts that may not be matched or even work when to get them
Hello
Kristijan tested both verision and he wrote he didn't heard any diference between the old and new type of transistors !
I don't know if it change the impedance , I dont think so!
JEAN HIRAGA - Le Monstre Amplifier PCB
Greetings
Kristijan tested both verision and he wrote he didn't heard any diference between the old and new type of transistors !
I don't know if it change the impedance , I dont think so!
JEAN HIRAGA - Le Monstre Amplifier PCB
Greetings
Ok perhaps he tested it and got the different impedances
Just to say it may sound like I Am being ungratefully to some of your help please don’t think this as this is not indented
So to Start Again
We need
2SC1775/2SK170
2SA872/2SJ74
2SB716/2SD756
Right I Have now source the 1775 so let’s say I have the 2SC1775 for the moment so ok
We have
2SC1775/2SK170
2SA872
2SJ74 Replacement is a 2SJ103
2S716 Replacement for is a 2SB647
/2SD756 Replacement for is a 2SC2632
So let’s say
Q1 2SC1775
Q3 2SK170
Q4 2SB647
Q5 2SA 872
Q7 2SJ103
Output
Q6 2SC5200
Q8 2SA1943
Please Note the replacements were recommended by my supplier
Just to say it may sound like I Am being ungratefully to some of your help please don’t think this as this is not indented
So to Start Again
We need
2SC1775/2SK170
2SA872/2SJ74
2SB716/2SD756
Right I Have now source the 1775 so let’s say I have the 2SC1775 for the moment so ok
We have
2SC1775/2SK170
2SA872
2SJ74 Replacement is a 2SJ103
2S716 Replacement for is a 2SB647
/2SD756 Replacement for is a 2SC2632
So let’s say
Q1 2SC1775
Q3 2SK170
Q4 2SB647
Q5 2SA 872
Q7 2SJ103
Output
Q6 2SC5200
Q8 2SA1943
Please Note the replacements were recommended by my supplier
Attachments
Last edited:
Hi Colin,
Don't worry - I can remember having trouble finding parts for the Monstre, and believe me, it's a lot harder down here in Brazil than up in Scotland!
From your last post it seems you are planning on switching the 2SJ74 for a 2SJ103 while keeping the 2SK170. I don't think this will work well - there is nothing wrong with the 2SJ103, but if you use it then you should also change the 2SK170 for 2SK246. This is because 2SJ74/2SK170 are a complementary pair, as are 2SJ103/2SK246. This isn't a big problem - anywhere you can find 2SJ103 you will probably find 2SK246 also. (Ampslab, linked above, for example.) You can keep the 2SK170 to use in some other project - there are loads of schematics on the Pass Labs forum here that use them.
I used a non-complementary jfet pair on the first one I built (8W version) and I had to mess around with the circuit a good deal to get dc offset down to sensible levels, which was really a pain, and I'm sure there were plenty of other things wrong with it as a result. There's no point in saving a little work finding the right parts now only to create work after the amp is built...
Similar things probably apply to the other pairs.
Cheers
Nigel
Don't worry - I can remember having trouble finding parts for the Monstre, and believe me, it's a lot harder down here in Brazil than up in Scotland!
From your last post it seems you are planning on switching the 2SJ74 for a 2SJ103 while keeping the 2SK170. I don't think this will work well - there is nothing wrong with the 2SJ103, but if you use it then you should also change the 2SK170 for 2SK246. This is because 2SJ74/2SK170 are a complementary pair, as are 2SJ103/2SK246. This isn't a big problem - anywhere you can find 2SJ103 you will probably find 2SK246 also. (Ampslab, linked above, for example.) You can keep the 2SK170 to use in some other project - there are loads of schematics on the Pass Labs forum here that use them.
I used a non-complementary jfet pair on the first one I built (8W version) and I had to mess around with the circuit a good deal to get dc offset down to sensible levels, which was really a pain, and I'm sure there were plenty of other things wrong with it as a result. There's no point in saving a little work finding the right parts now only to create work after the amp is built...
Similar things probably apply to the other pairs.
Cheers
Nigel
Hello
I say the same , when you have a transistor, fet or JFet please look up the complementary parts . You can't replace the 2SJ74BL with 2SJ103BL and leave the 2SK170BL . They will not work properly together...
At JFet you have to pay attention what grade BL ,GR ,V ,Y etc .
Even if they are complementary pairs and one is BL grade , the pair is GR not the best idea to use them !
You will end up with a big offset and that just a small problem.
These is the original Hiraga Le Monstre!
For example
2SJ74BL complementary pair 2SK170BL
2SA872E ------------------ 2SC177E
2SB716 -------------------2SD746
2SB754---------------------2SD844
If you change the NPN you have to find the complementary part PNP and change that to.
The transistors has different MHz (speed), pF(capacitance) , etc .Those are very important!
That is why you can not exchange them!
Other wise you end up with a mess.
I built these amp , I sold at least 80 kits with home made PC board no complain at all.
I wrote on the Ebay you can get matched (important that to) pair 2SJ74BL & 2SK170BL .
You have to buy them !In case if they aren't matched you end up one side sound different than another !
Seriously!
The black end white the original schematic! If you want the orig Le Monstre please use that!
Believe me better to get the right parts from the begening , atherwise you will spend much more .
I just want to help !
Greetings
I say the same , when you have a transistor, fet or JFet please look up the complementary parts . You can't replace the 2SJ74BL with 2SJ103BL and leave the 2SK170BL . They will not work properly together...
At JFet you have to pay attention what grade BL ,GR ,V ,Y etc .
Even if they are complementary pairs and one is BL grade , the pair is GR not the best idea to use them !
You will end up with a big offset and that just a small problem.
These is the original Hiraga Le Monstre!
For example
2SJ74BL complementary pair 2SK170BL
2SA872E ------------------ 2SC177E
2SB716 -------------------2SD746
2SB754---------------------2SD844
If you change the NPN you have to find the complementary part PNP and change that to.
The transistors has different MHz (speed), pF(capacitance) , etc .Those are very important!
That is why you can not exchange them!
Other wise you end up with a mess.
I built these amp , I sold at least 80 kits with home made PC board no complain at all.
I wrote on the Ebay you can get matched (important that to) pair 2SJ74BL & 2SK170BL .
You have to buy them !In case if they aren't matched you end up one side sound different than another !
Seriously!
The black end white the original schematic! If you want the orig Le Monstre please use that!
Believe me better to get the right parts from the begening , atherwise you will spend much more .
I just want to help !
Greetings
Attachments
Hi
OK yes I know you are trying to help and thank you for that
please take a look at this list taken from my supplier now maybe you can see why I am confused as to which transistors i require the complement are the transistors that i have pleas take a look for your selfs at Cricklewood Electronics - CCTV. CCTV Equipment. CCTV Systems. Digital CCTV Cameras
Part No.: 2SA872A
PNP TO92 ECB 120V 50mA 200MHz Very Low Noise Audio. Complement to 2SC1775A
Part No.: 2SC1775A
NPN TO92 ECB 120V 50mA 200MHz Very Low Noise Audio. Complement to 2SA872A
Part No.: 2SJ74
PFET TO92 go to 2SJ103
Part No.: 2SB716
2SB716 PNP TO92 ECB Suggested Equivalent: 2SB647
Part No.: 2SD756
NPN TO92 ECB go to 2SC2632
Hi Colin,
They are sending you to parts they have, instead of ones that are obsolete and therefore they don't have. This is sometimes a big help, I guess, except it's not in this case. If you are designing a circuit then you can (sometimes, I guess) change other things to make the 2SJ103 work instead of the 2SJ74, for example. In the case of the Monstre, however, the jfets are paired with another (in this case the 2SJ74 is paired with the 2SK170) which is very similar but of opposite polarity. If you want to redesign the circuit to use 2SJ103 you can, but you need to switch to 2SK246 also, which is exactly what the "modern equivalents" circuit does.
People who know understand schematics better than I do can explain it better, but the bottom line is that you shouldn't suppose their website is saying that 2SJ103 is a "drop-in" replacement for 2SJ74.
Cheers
Nigel
Hello
The 2SA872A & 2SC1775A OK
2SB716 not equal with 2SB647
2SB716 pdf, 2SB716 description, 2SB716 data sheets, 2SB716 view ::: ALLDATASHEET :::
http://www.datasheetcatalog.org/datasheet/HitachiSemiconductor/mXyzuyvu.pdf
Please look at the Gain bandwidth fT the replacement has140MHz the orig has 150MHZ
that would be OK
Also the capacitance COB the replacement has 20pF the orig has 1.8pF
These a big difference
If you use 2SB647/A please use 2SD667/A with it
Those are complementary parts!
Please do not use the ECG catalog ,look up the parts on the Net
So 2SB647/A goes with 2SD667/A The JFet you can not replace with 2SJ103 , you must find 2SJ74BL if you have 2SK170BL!
There are lot of parts even matched parts on Ebay!
I know the extra cost but you must have to have .
Also if you have unmatched complementary parts the two side will sound differently!The easiest think you buy matched parts , or have to buy enough to matched hfE at transistors
IGS at JFets
I know life is not easy , but you must get the parts which work well together!
Greetings
The 2SA872A & 2SC1775A OK
2SB716 not equal with 2SB647
2SB716 pdf, 2SB716 description, 2SB716 data sheets, 2SB716 view ::: ALLDATASHEET :::
http://www.datasheetcatalog.org/datasheet/HitachiSemiconductor/mXyzuyvu.pdf
Please look at the Gain bandwidth fT the replacement has140MHz the orig has 150MHZ
that would be OK
Also the capacitance COB the replacement has 20pF the orig has 1.8pF
These a big difference
If you use 2SB647/A please use 2SD667/A with it
Those are complementary parts!
Please do not use the ECG catalog ,look up the parts on the Net
So 2SB647/A goes with 2SD667/A The JFet you can not replace with 2SJ103 , you must find 2SJ74BL if you have 2SK170BL!
There are lot of parts even matched parts on Ebay!
I know the extra cost but you must have to have .
Also if you have unmatched complementary parts the two side will sound differently!
The easiest think you buy matched parts , or have to buy enough to matched hfE at transistorsIGS at JFets
I know life is not easy , but you must get the parts which work well together!
Greetings
Last edited:
Yep thank you Lads
Yes when I ordered the transistors I emailed then first to check if they had the originals and the list I posted up here was what they came back with as equivalents It just shows you can’t trust them all the time they even said they had the 2SC1775 but it was out of spec Here is the email they sent me
Sorry to say, but when we checked the latest batch of 2SC1775A we found they
were out of spec (low gain) so we withdrew them from sale.
We are expecting a new batch in a few days.
If this is inconvenient, we can refund you or send you alternatives
(2SC2240) although they are slightly lower gain and half the price. (We
could send 4).
Best Regards
Syd
I didn’t know a transistor could be out of spec I mean a 2SC1775 is a 2SC1775 isn’t it
So looks like I should stop using them unless I no the transistors I want
Yes I an afraid I can become very confused with my PNP and NPNs yes I will order matched pairs of eBay as you all have said it’s the easteyet way
Again thank you for your help and patients
Yes when I ordered the transistors I emailed then first to check if they had the originals and the list I posted up here was what they came back with as equivalents It just shows you can’t trust them all the time they even said they had the 2SC1775 but it was out of spec Here is the email they sent me
Sorry to say, but when we checked the latest batch of 2SC1775A we found they
were out of spec (low gain) so we withdrew them from sale.
We are expecting a new batch in a few days.
If this is inconvenient, we can refund you or send you alternatives
(2SC2240) although they are slightly lower gain and half the price. (We
could send 4).
Best Regards
Syd
I didn’t know a transistor could be out of spec I mean a 2SC1775 is a 2SC1775 isn’t it
So looks like I should stop using them unless I no the transistors I want
Yes I an afraid I can become very confused with my PNP and NPNs yes I will order matched pairs of eBay as you all have said it’s the easteyet way
Again thank you for your help and patients
Hello
The 2SC2240 total different transistor , different pin out etc.
Do not take that!
If you want a good amp (I think that is the reason you DIY) do yourself a favour ,just use the original parts !
And if you can get matched pairs it worth to pay some extra and you will be sure both channel sound the same.
These people in the store they want to sell what ever they have . They look up at the ECG book the replacement,they make money .
I would not take different (replacement parts) just what I ordered )or MONEY BACK!
There is no such think out of spec (probably fake parts) hard to find parts! No longer at production! Toshiba stop produce 2SC1775.
The reason I want to buy produced by Sanyo , after the data (at least that good or even better parts) .
But I will see , I had these amp , I prefer the Class A.. To me that amp is closer to my taste .
But the Le Monstre not bad either!
Greetings
The 2SC2240 total different transistor , different pin out etc.
Do not take that!
If you want a good amp (I think that is the reason you DIY) do yourself a favour ,just use the original parts !
And if you can get matched pairs it worth to pay some extra and you will be sure both channel sound the same.
These people in the store they want to sell what ever they have . They look up at the ECG book the replacement,they make money .
I would not take different (replacement parts) just what I ordered )or MONEY BACK!
There is no such think out of spec (probably fake parts) hard to find parts! No longer at production! Toshiba stop produce 2SC1775.
The reason I want to buy produced by Sanyo , after the data (at least that good or even better parts) .
But I will see , I had these amp , I prefer the Class A.. To me that amp is closer to my taste .
But the Le Monstre not bad either!
Greetings
I would not be so worried about transistors.
Even BC547B/BC557B can work well.
The difference is so minimal, that you can never hear it with your ears.
If you measure distortion you may see a slight difference.
BC550C/BC560C are excellent and low noise variants.
Easy to find in most shops. They are very low in price, but good!
They have high gain, because they are have 'C'.
BC547B is normal gain, because have 'B'
Even BC547B/BC557B can work well.
The difference is so minimal, that you can never hear it with your ears.
If you measure distortion you may see a slight difference.
BC550C/BC560C are excellent and low noise variants.
Easy to find in most shops. They are very low in price, but good!
They have high gain, because they are have 'C'.
BC547B is normal gain, because have 'B'
Hi Colin,
I agree with lineup. The "modern equivalents" circuit uses BC550/560, as did both of my Monstre builds. I'm sure the original transistors also work well, perhaps better, but I believe the jfet pair makes the biggest difference - and gaborbela is right about using a matched set, if you can get them, but getting the complementary parts is the most important thing, IMHO.
Cheers
Nigel
I agree with lineup. The "modern equivalents" circuit uses BC550/560, as did both of my Monstre builds. I'm sure the original transistors also work well, perhaps better, but I believe the jfet pair makes the biggest difference - and gaborbela is right about using a matched set, if you can get them, but getting the complementary parts is the most important thing, IMHO.
Cheers
Nigel
Hello
BC550C/560C great transistor , try to get both from the same company , like Philips etc.
Also U can use ZTX transistors , you can find them at Great B.
ZTX450/550 for small signal
ZTX653/753 for driver
Those are great transistors , just pay attention the pin out different . You can twist the lead of them.
2SK170BL /2SJ74BL must , do not replace it with 2SJ103BL or if you do you have to replace the 2SK170BL to with 2SK246BL to!
But after my experience 2SK170BL/4SJ74BL would be the best choice.
Do you have the original power transistors , or you plan to use something else?
Greetings
gabor
BC550C/560C great transistor , try to get both from the same company , like Philips etc.
Also U can use ZTX transistors , you can find them at Great B.
ZTX450/550 for small signal
ZTX653/753 for driver
Those are great transistors , just pay attention the pin out different . You can twist the lead of them.
2SK170BL /2SJ74BL must , do not replace it with 2SJ103BL or if you do you have to replace the 2SK170BL to with 2SK246BL to!
But after my experience 2SK170BL/4SJ74BL would be the best choice.
Do you have the original power transistors , or you plan to use something else?
Greetings
gabor
Boy you guys like to confuse a beginner
Are you saying none of the transistors I have listed will work with the schematic I posted could you pleas just post the part numbers I require for
Q1
Q2
Q3
Q4
Q5
And suggest a good transistor for Q6/7 in place of the 2N types
And if you can do the same for the updated version that uses the BC550C/560C transistor
This will give me Better choices on which one to build I think this will be much easier than talking about comp pairs that are not used but I have taken note of all your posts which will help in understanding the different transistors Valves are must easer
Thanks
Are you saying none of the transistors I have listed will work with the schematic I posted could you pleas just post the part numbers I require for
Q1
Q2
Q3
Q4
Q5
And suggest a good transistor for Q6/7 in place of the 2N types
And if you can do the same for the updated version that uses the BC550C/560C transistor
This will give me Better choices on which one to build I think this will be much easier than talking about comp pairs that are not used but I have taken note of all your posts which will help in understanding the different transistors Valves are must easer
Thanks
Hello
I still don't know what you have at your hand.
From these schematic
2SJ74BL or (Y)/ 2SK170BL or(Y) I think must !
Y the original but hard to find it , BL popular , you have to adjust the 2PC 1K resisters to set up the right bias.
Second line you can use BC550C/560C how Lineup advised
I would rather use ZTX450/550 (I think better quality)
Here you must care about the different pin out of the transistors!
For driver stage I would use also ZTX653 / ZTX753 . Different pin out , take care about that!
For power transistor if you use TO3 can (metal can)
MJ15022/23 great transistors or MJ15024/25I would try these if I do not have the orig semis. We advise the original because those were properly put together . Someone invested time and energy to achive these result.
That not mean you can not achive the same result or even better .
But to have the orig that would give the right base.
You can upgrade it .
If I wouldn't have the orig I would try these list .
Greetings
I still don't know what you have at your hand.
From these schematic
2SJ74BL or (Y)/ 2SK170BL or(Y) I think must !
Y the original but hard to find it , BL popular , you have to adjust the 2PC 1K resisters to set up the right bias.
Second line you can use BC550C/560C how Lineup advised
I would rather use ZTX450/550 (I think better quality)
Here you must care about the different pin out of the transistors!
For driver stage I would use also ZTX653 / ZTX753 . Different pin out , take care about that!
For power transistor if you use TO3 can (metal can)
MJ15022/23 great transistors or MJ15024/25I would try these if I do not have the orig semis. We advise the original because those were properly put together . Someone invested time and energy to achive these result.
That not mean you can not achive the same result or even better .
But to have the orig that would give the right base.
You can upgrade it .
If I wouldn't have the orig I would try these list .
Greetings
Attachments
Last edited:
Ok perhaps he tested it and got the different impedances
Just to say it may sound like I Am being ungratefully to some of your help please don’t think this as this is not indented
So to Start Again
We need
2SC1775/2SK170
2SA872/2SJ74
2SB716/2SD756
Right I Have now source the 1775 so let’s say I have the 2SC1775 for the moment so OK
We have
2SC1775/2SK170
2SA872
2SJ74 Replacement is a 2SJ103 No good
2S716 Replacement for is a 2SB647
/2SD756 Replacement for is a 2SC2632
So let’s say
Q1 2SC1775
Q3 2SK170 ??? what grade (BL, GR,V) need 2SJ74 same grade
Q4 2SB647 I would not use these specially with 2SC2632 not complementary pairs
Q5 2SA 872Q7 2SJ103 NO!Output
Q6 2SC5200
Q8 2SA1943 Please Note the replacements were recommended by my supplier
Hello
I see your list
You wrote 2SC1775 you dont have so Q5 is out to
Q3 2SK170BL is OK but only with 2SJ74BL , so Q7 is out
Only the output is OK but who knows those are real Toshiba parts??
Toshiba last 13 years or so not produced not one of these!
Greetings
Last edited: