Daniel, good to see you went ahead and are building the Hiraga. Sometimes photos are deceiving, but thar heatsink does look a bit small. I built my Hiragas as a pair of monoblocks, and gave each output transistor a huge heatsink and event then they ran on the hot side ( 60 deg. celcius on surface, to be exact). Take a look at the pic bellow to see what I mean. Also running 35V rails at 2A quiescent.
Anyway, great amp - loved the midrange and truthness of tone. Unfortunately it didn't drive my ATCs very well in the bass region, so I tore them apart and I'm building a design by a Scandinavian fellow named Nygaard.
Good luck on your project
J.Guilherme
Anyway, great amp - loved the midrange and truthness of tone. Unfortunately it didn't drive my ATCs very well in the bass region, so I tore them apart and I'm building a design by a Scandinavian fellow named Nygaard.
Good luck on your project
J.Guilherme
Hello,
Guilherme you are absolutely right about the heatsink. The heatsink sold in Paris did have a thermal resisistance of 0,9 celsius/watt and there was just one transistor on each of the four of them. My last chassis did i did use for my 30 watt hiraga had a krell-like chassis using one heatsink for 2 transistors, But it was a massive heatsink ( more then 1 kilogram) but it still got hot. With metal prices going up it is getting difficult to get good heatsinks for this kind of amps for a reasonable price. Greetings, Eduard
Guilherme you are absolutely right about the heatsink. The heatsink sold in Paris did have a thermal resisistance of 0,9 celsius/watt and there was just one transistor on each of the four of them. My last chassis did i did use for my 30 watt hiraga had a krell-like chassis using one heatsink for 2 transistors, But it was a massive heatsink ( more then 1 kilogram) but it still got hot. With metal prices going up it is getting difficult to get good heatsinks for this kind of amps for a reasonable price. Greetings, Eduard
HI all!
thanks MJL21193,
Probably going to leave the caps blue or perhaps paint them red or something (unsure at the moment...) didnt think of polishing them...
I am jealous that you have the origional transistors! the original 2SA627/2SD188 are so hard to find now !
let me know if you have some more laying around !!!
currently I have origional spec 2SC1775A(E)/2SA872A(E) all hfe matched and 2SA634/2SC1096 (NEC) only my output stage is a little bit upgraded for higher power output.
u should build it ! I have only listened to one channel mono but its very promising....
Zen Mod,
If you do get the CD-ROMS i think you will be happy there is alot of good info and they are layed out very well in terms of finding info.
Guilherme,
Nice setup !!!
I agree with you about the heatsinks,
the heatsinks pictured are approx 75 x 300 x 35 ~0.37C/W (x4)
i have decided not to use these in the final chassis. I have some larger ones which i will probably use, I think i will end up with approx 34V rails and 1-2 A bias. and i would prefer not to burn people.!!
Interesting you found the bass response was lacking i have listened and measured and it seems good to me. then again 6 x 0.2F will help
-Dan
thanks MJL21193,
Probably going to leave the caps blue or perhaps paint them red or something (unsure at the moment...) didnt think of polishing them...
I am jealous that you have the origional transistors! the original 2SA627/2SD188 are so hard to find now !
let me know if you have some more laying around !!!
currently I have origional spec 2SC1775A(E)/2SA872A(E) all hfe matched and 2SA634/2SC1096 (NEC) only my output stage is a little bit upgraded for higher power output.
u should build it ! I have only listened to one channel mono but its very promising....
Zen Mod,
If you do get the CD-ROMS i think you will be happy there is alot of good info and they are layed out very well in terms of finding info.
Guilherme,
Nice setup !!!
I agree with you about the heatsinks,
the heatsinks pictured are approx 75 x 300 x 35 ~0.37C/W (x4)
i have decided not to use these in the final chassis. I have some larger ones which i will probably use, I think i will end up with approx 34V rails and 1-2 A bias. and i would prefer not to burn people.!!
Interesting you found the bass response was lacking i have listened and measured and it seems good to me. then again 6 x 0.2F will help
-Dan
u should build it ! I have only listened to one channel mono but its very promising....
One thing that I really liked about the Hiraga was the soundstage. I was very impressed with some recordings where the voice of the singer would come from the center in such a convincing manner that it was hard to believe there was nothing but air between those speakers. So hurry up building that second channel
J.Guilherme
One thing that I really liked about the Hiraga was the soundstage. I was very impressed with some recordings where the voice of the singer would come from the center in such a convincing manner that it was hard to believe there was nothing but air between those speakers. So hurry up building that second channel
J.Guilherme
Hello Daniel,
I did take a closer look at your pictures and i think it will be difficult to incorporate these chokes somewhere. Because my job is about making holes in metal sheets i know the trouble you have been through???
If your chassis layout is close to the one used by the original hiraga. You could try mounting the choke under the first capacitor with some long-sized stand-offs . If they are potted and to high you can make a rectangular or square hole in the bottomplate. This way you can gain some soace if the feed you are using are a few centimeters high. The amp once completely finished will get quiet hot. On the cd-rom you can read that they did spend a lot of time to improve heat circulation in the chassis. Mounting the heatsinks with their '' backs '' against the sides of the chassis will cool them down but will make life hard for the capacitors. Mounting them with sturdy stand-offs about 15 mm long will create a kind of chimney effect so air can rise on all sides of the heat sink. I remember Hiraga did talk about this before making the chassis that was widely known as le classe A.
The replcement for the original power transistors were considered better by the magazine and all the people that did build these monsters. Maybe some french internet sites have more updates on the hiraga amps. BUT this amp was described as a perfect marriage of design and choice of components. Why not use a regulated power supply?
The 8 watt hiraga which did get his name le monstre from a stax 8 watt amplifier using a 1200 va power transformer has been elaborated using more capacitors, car batteries, supercapa. Hiraga then did write that regulated power supplies did have advantages but sonically using no active components was the way to go.
I think if 30 watt power output will not be enough then 35 watt will not be enough either. I think you will need a big choke to make it work like a choke input. Using 200mhenry there would probably give the the voltage a huge swing when switching on. It used to be easy to get 20 henry tango chokes suitable for choke-input tube designs. They were not exactly cheap ( even when bought in Japan) but i did buy eight at once after having tried one. Using a choke-input for a hiraga amp will make the voltage drop close to the original ones. I do have some chokes 100mh 1,3 ohm 1,3A potted and 400mh 4,2 ohm 2A not potted. The ones in the hiraga were 200mh not potted. I remember switching to a choke-input with my tube amps ( which also meant using another power transformer ( same VA) to compensate the voltage drop did give it more authority. If one day i will switch to bi-amping and using solid state for the bass i would surely get myself a choke input power supply. They will be at least 10 cubic centimeters make it 15 to be sure but it will be more beneficial than doubling the va of the power transformer.
If you would be in europe i would lend you a pair to give it a try. But now i realize you use the same powersupply for both channels so the 100mh will be tortured to much. Allthough it is a professional part ( made by bourdeau something like French Emt ) it will probably have a short life or the induction will drop to much.
Greetings, Eduard
I did take a closer look at your pictures and i think it will be difficult to incorporate these chokes somewhere. Because my job is about making holes in metal sheets i know the trouble you have been through???
If your chassis layout is close to the one used by the original hiraga. You could try mounting the choke under the first capacitor with some long-sized stand-offs . If they are potted and to high you can make a rectangular or square hole in the bottomplate. This way you can gain some soace if the feed you are using are a few centimeters high. The amp once completely finished will get quiet hot. On the cd-rom you can read that they did spend a lot of time to improve heat circulation in the chassis. Mounting the heatsinks with their '' backs '' against the sides of the chassis will cool them down but will make life hard for the capacitors. Mounting them with sturdy stand-offs about 15 mm long will create a kind of chimney effect so air can rise on all sides of the heat sink. I remember Hiraga did talk about this before making the chassis that was widely known as le classe A.
The replcement for the original power transistors were considered better by the magazine and all the people that did build these monsters. Maybe some french internet sites have more updates on the hiraga amps. BUT this amp was described as a perfect marriage of design and choice of components. Why not use a regulated power supply?
The 8 watt hiraga which did get his name le monstre from a stax 8 watt amplifier using a 1200 va power transformer has been elaborated using more capacitors, car batteries, supercapa. Hiraga then did write that regulated power supplies did have advantages but sonically using no active components was the way to go.
I think if 30 watt power output will not be enough then 35 watt will not be enough either. I think you will need a big choke to make it work like a choke input. Using 200mhenry there would probably give the the voltage a huge swing when switching on. It used to be easy to get 20 henry tango chokes suitable for choke-input tube designs. They were not exactly cheap ( even when bought in Japan) but i did buy eight at once after having tried one. Using a choke-input for a hiraga amp will make the voltage drop close to the original ones. I do have some chokes 100mh 1,3 ohm 1,3A potted and 400mh 4,2 ohm 2A not potted. The ones in the hiraga were 200mh not potted. I remember switching to a choke-input with my tube amps ( which also meant using another power transformer ( same VA) to compensate the voltage drop did give it more authority. If one day i will switch to bi-amping and using solid state for the bass i would surely get myself a choke input power supply. They will be at least 10 cubic centimeters make it 15 to be sure but it will be more beneficial than doubling the va of the power transformer.
If you would be in europe i would lend you a pair to give it a try. But now i realize you use the same powersupply for both channels so the 100mh will be tortured to much. Allthough it is a professional part ( made by bourdeau something like French Emt ) it will probably have a short life or the induction will drop to much.
Greetings, Eduard
eduard said:
Did you see my little version of "Le monstre" ?
the link on my signature line below,
this particular amp had the imaging effect you mentioned and i am building the "Le class A" to achieve similar sonics with a little more power. ~30-50W
Interestingly the "le monstre" I built barely made 8W however sounds alot more powerful.
-Dan
Hello Daniel,
I did see your monster. It is a baby monster. The people in France did use high efficiency loudspeakers to compare electronics. I did build the 30 watt because at that time i did have low eff. transmission lines.
L'' audiophile did sell the fostex 103 ( low eff but difficult to drive) triangle tqwt 95 db, onken bass cabinets around 99, altec vots bass cabinets 103 db, tad 2001 with sandfilled horns 109 db. The 8 watt offered by the monster equipped with a huge power supply will make you shiver.
In the eighties i did built the hiraga mc amplifier called le pre pre. Using lead batteries, 470000MF caps. The author ( called Chretien) did explain the reason for using the caps by saying that these caps have a much lower esr and batteries also make noise because of the chemical process. Because of the very small signals generated by the cartridge this noise will mask some of the music so it should be reduced as much as possible. Chretien did compare it to a balance to weigh very light objects. It has to be heavy as hell to do so.
Musical signals related to recreate ambiance are said to be extremely small so if there are signals coming from the power supply overruling these even smaller signals the holographic image will be gone.
Number 36 of l'audiophile did describe le monstre using 2 12 volts 40ah car batteries in 1985!! Completely charged it will give you about 3 and a half hour of listening pleasure. Giving each channel their own batteries will double this. Maybe modern technology batteries have a bigger ah for the same price and or volume.
I remember my PREPRE was allways in charging mode except during listening sessions but it did use sealed batteries not the kind used in cars.
Greetings, eduard
P.s get these cd-roms and be amazed
I did see your monster. It is a baby monster. The people in France did use high efficiency loudspeakers to compare electronics. I did build the 30 watt because at that time i did have low eff. transmission lines.
L'' audiophile did sell the fostex 103 ( low eff but difficult to drive) triangle tqwt 95 db, onken bass cabinets around 99, altec vots bass cabinets 103 db, tad 2001 with sandfilled horns 109 db. The 8 watt offered by the monster equipped with a huge power supply will make you shiver.
In the eighties i did built the hiraga mc amplifier called le pre pre. Using lead batteries, 470000MF caps. The author ( called Chretien) did explain the reason for using the caps by saying that these caps have a much lower esr and batteries also make noise because of the chemical process. Because of the very small signals generated by the cartridge this noise will mask some of the music so it should be reduced as much as possible. Chretien did compare it to a balance to weigh very light objects. It has to be heavy as hell to do so.
Musical signals related to recreate ambiance are said to be extremely small so if there are signals coming from the power supply overruling these even smaller signals the holographic image will be gone.
Number 36 of l'audiophile did describe le monstre using 2 12 volts 40ah car batteries in 1985!! Completely charged it will give you about 3 and a half hour of listening pleasure. Giving each channel their own batteries will double this. Maybe modern technology batteries have a bigger ah for the same price and or volume.
I remember my PREPRE was allways in charging mode except during listening sessions but it did use sealed batteries not the kind used in cars.
Greetings, eduard
P.s get these cd-roms and be amazed
Hi Eduard,
I have the CD roms
I have seen the photos of the origional Le monstre and i think it is nice however i have about 84dB effiency speakers so i want the 30W+
Yeah when the orgional Le monstre was made (1980) i was less than 1 year old the year i was born
109dB effciency is huge !!! were these very expensive speakers ?
-Dan
I have the CD roms
I have seen the photos of the origional Le monstre and i think it is nice however i have about 84dB effiency speakers so i want the 30W+
Yeah when the orgional Le monstre was made (1980) i was less than 1 year old
the year i was born109dB effciency is huge !!! were these very expensive speakers ?
-Dan
hello,
Also read the thread '' has anyone used an lc power supply........ in the pass labs directory. Read the link mentioned by another dutch person called Boers about filament supplies. The choke used by l''audiophile did have a bigger inductance 200millihenry and it wasn't used for choke-input . But i think just like tube design there would be something like a critical induction to make it work like a real choke input. That would be the way to go if i would be still using solid state amps. It wouldn't be a problem to spend 300 euro or 400$ for the 2 chokes needed. So far every circuit did improve a lot after using a choke input Give it a try. I think Cello also did do it in the past. A choke doesn't go bad after 15 years like a regular cap so it is a very good investment with metal prices increasing day by day. Using a primary section of a power transformer can be cheap but you will not get a lot of induction and a lot wire isn't used at all and you need an air gap. It should be easy to make some because it is easier than iron with multiple windings. Get it vacuum impregnated and potted ( shielded?) and post your findings here greetings, eduard
Also read the thread '' has anyone used an lc power supply........ in the pass labs directory. Read the link mentioned by another dutch person called Boers about filament supplies. The choke used by l''audiophile did have a bigger inductance 200millihenry and it wasn't used for choke-input . But i think just like tube design there would be something like a critical induction to make it work like a real choke input. That would be the way to go if i would be still using solid state amps. It wouldn't be a problem to spend 300 euro or 400$ for the 2 chokes needed. So far every circuit did improve a lot after using a choke input Give it a try. I think Cello also did do it in the past. A choke doesn't go bad after 15 years like a regular cap so it is a very good investment with metal prices increasing day by day. Using a primary section of a power transformer can be cheap but you will not get a lot of induction and a lot wire isn't used at all and you need an air gap. It should be easy to make some because it is easier than iron with multiple windings. Get it vacuum impregnated and potted ( shielded?) and post your findings here greetings, eduard
Daniel,
They have been described in an article called le pavillion sable written by le dauphin. They were expensive the horns plus the drivers for stereo about 4000 euro if i remember well. Good investment though.
With 84db you will need the 30 watt . Imean 8 watt will be not enough to stress the neighbours. BUT i think the power is coming from the power supply
Organise a group buy for some chokes. I did see a transformer company from ukraine on this ite a few days ago But it will cost a lost to transport to australia and i think any transformer company could make a pair Greetings, Eduard
They have been described in an article called le pavillion sable written by le dauphin. They were expensive the horns plus the drivers for stereo about 4000 euro if i remember well. Good investment though.
With 84db you will need the 30 watt . Imean 8 watt will be not enough to stress the neighbours. BUT i think the power is coming from the power supply
Organise a group buy for some chokes. I did see a transformer company from ukraine on this ite a few days ago But it will cost a lost to transport to australia and i think any transformer company could make a pair Greetings, Eduard
Hello Daniel,
If i would be able to wind my own chokes i would certainly do so. Are they big enough to make chokes for a choke-input power supply for your new amp? Probably you will have to make them vacuum impregnated to stop them from being noisy. Get a square iron tube ( or is a tube allways round? ) and put the choke inside surrounded by some kind of epoxy.
Right now i did switch to tube design but i wouldcertainly be interested in building a solid state with a choke input power supply if i wouldn't have has a 104 db system.
Did you read the thread i did tell refer to a few post ago? i am not interested in electronics to much because most of the time i just don't get it but this article did strenghten my opinion about choke inputs Greetings, Eduard
If i would be able to wind my own chokes i would certainly do so. Are they big enough to make chokes for a choke-input power supply for your new amp? Probably you will have to make them vacuum impregnated to stop them from being noisy. Get a square iron tube ( or is a tube allways round? ) and put the choke inside surrounded by some kind of epoxy.
Right now i did switch to tube design but i wouldcertainly be interested in building a solid state with a choke input power supply if i wouldn't have has a 104 db system.
Did you read the thread i did tell refer to a few post ago? i am not interested in electronics to much because most of the time i just don't get it but this article did strenghten my opinion about choke inputs Greetings, Eduard
Hello
Here is the link that should convince the hiraga fans to start searching for chokes.http://www.clarisonus.com/Research Reports/RR002-DCFilterTest/RR002-DCFilSupplyTest.html
Here is the link that should convince the hiraga fans to start searching for chokes.http://www.clarisonus.com/Research Reports/RR002-DCFilterTest/RR002-DCFilSupplyTest.html
eduard said:
Eduard Excellent article!
This information can be applied to linear supplies in general.
It is useful to read when people do some actual testing !
I am biased as i am employed as an electrical/electronics safety testing officer
I guess the 300B is close to an amplifier in its purest / simplest form
really would benefit from a very low ripple filament supply because it is a directly heated triode. In that application subtle differences in topology can perhaps create noticable differences in sonics.
any how, I am convinced to wind a couple of inductors in place of the resistors.
-Dan
HI
I have built that amp and I can tel you it is way mutch better amp than the Aleph30 .But I have to let you know right away diferent people diferent taste .
I have both amp and I would prefer the Class A over the Aleph30 but not over the AlephX .
If you are interested I ca let you know what type of transistors I use .I had the oportunity to give a try the original transistors but I find much better than the orig.
Righ now I want to give a try for a flat back transistor because I can solder that direct to the PC board .
Regards
I have built that amp and I can tel you it is way mutch better amp than the Aleph30 .But I have to let you know right away diferent people diferent taste .
I have both amp and I would prefer the Class A over the Aleph30 but not over the AlephX .
If you are interested I ca let you know what type of transistors I use .I had the oportunity to give a try the original transistors but I find much better than the orig.
Righ now I want to give a try for a flat back transistor because I can solder that direct to the PC board .
Regards
Someone recently posted a link to this truly excellent book:
OnSemi Rectifier Applications Handbook.
Take a look at Chapters 5 and 7, discussing all our standard rectifier and filter circuits in full detail.
Chapters 13 and 15 are also worth a reading (these deal with cooling and mounting issues of power semiconductors).
- Klaus
OnSemi Rectifier Applications Handbook.
Take a look at Chapters 5 and 7, discussing all our standard rectifier and filter circuits in full detail.
Chapters 13 and 15 are also worth a reading (these deal with cooling and mounting issues of power semiconductors).
- Klaus
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