Hmm, so by reducing 10 ohm or increasing 220 ohm in the feedback loop i get more "return power" in the input, is there a downside? witch resistor do you recommend changing and to what value?
I'm no electro engineer so bare with me Please 🙂
throw in a teaser
I'm no electro engineer so bare with me Please 🙂
throw in a teaser
I have discussed a bit with a colleague of mine about doubling the value of the 220 ohm resistor. what do you think about that, is there a downside by doing this?
My test speakers isn't that effective (89 - 90 db), but i think it should be louder than this.
I intend to build speakers dedicated to this amp, with high sensitivity.
My test speakers isn't that effective (89 - 90 db), but i think it should be louder than this.
I intend to build speakers dedicated to this amp, with high sensitivity.
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Yes you have halved the feedback and consequently increased the distortion and output impedence. This cannot fail but to have an impact on the overall sound of the amplifier.
Your test speakers are very low sensitivity for this type of amplifier, you should consider using more sensitive speakers as your overall solution. i cannot recommend messing with the feedback.
Shoog
Your test speakers are very low sensitivity for this type of amplifier, you should consider using more sensitive speakers as your overall solution. i cannot recommend messing with the feedback.
Shoog
i have build the 30w edition with 2sa1943 and 2sc5200 toshibas runing at 35volts and it sounds good
I used my Monstre with 85 dB speakers; never felt it lacked power but didn't aim for earsplitting spl either.
How much capacitance do you have in the PS?
Cheers
Johan
PS I actually preferred Monstre over 30W Hiraga but differences were subtle so YMMV
38400μF but the current is not regulated,only rectified...can anyone suggect a regulation scheme?
Your 38400 seems a bit low.
Although the original might be overkill I would suggest experimenting with more.
Original here: The Class-A Amplifier Site - Hiraga 'The Monster'
Cheers,
Johan
Although the original might be overkill I would suggest experimenting with more.
Original here: The Class-A Amplifier Site - Hiraga 'The Monster'
Cheers,
Johan
i wouldnt say its not enough and i doubt higher values have audible effects...but anyway my main concern is the regulation which i dont have right now...
tasos
tasos
Hi Tasos, please read post #1192 and #1193 the regulation psu and caps multiplier.
regards,
JOsh
regards,
JOsh
I actually found out that i had R1 and R2 interchanged
, have soldered them in their right position now. Will do a proper test after work tomorrow 🙂Have 2x22000uF Kemet caps per channel.
I have got some voltage regulator PCBs for sale. They are professionally designed and built following the schematic wich was introduced with the Kaneda power amp. Currently they are assembled to deliver ~13V at the output but they can be easily adjusted to any voltage. I use them togehter with JIMS audio le monstre PCBs, and they can be perfectly mounted back to back. Send me a PN if you are interested in a pair or two of the boards.
Fake 2SJ74s anyone?
Two weeks ago a asked a "nice" chinese seller (goodtronic) how he insures that his parts were genuine. This is what he answered:
"Sorry... I think this 2sj74 is not very good one... "
The german seller i just got 8 pieces at €4,76 a pop from was not so nice. She asured me that every single FET was checked for authenticity.
Well the 2SJ74s I got used to be J270s in their earlier life...
I am so annoyed - I will have a hard time sleeping tonight.
The hunt for the parts of this amp is highly aggrevating.
Anybody know a good source for 2sj74 at the moment?
Did anybody buy here lately:
Transistor HITACHI 2SJ74-BL - Transistors audio
(Hitachi???)
€3 a piece would be OK if genuine.
Two weeks ago a asked a "nice" chinese seller (goodtronic) how he insures that his parts were genuine. This is what he answered:
"Sorry... I think this 2sj74 is not very good one... "
The german seller i just got 8 pieces at €4,76 a pop from was not so nice. She asured me that every single FET was checked for authenticity.
Well the 2SJ74s I got used to be J270s in their earlier life...
I am so annoyed - I will have a hard time sleeping tonight.
The hunt for the parts of this amp is highly aggrevating.
Anybody know a good source for 2sj74 at the moment?
Did anybody buy here lately:
Transistor HITACHI 2SJ74-BL - Transistors audio
(Hitachi???)
€3 a piece would be OK if genuine.
My friend is building a cab for Hiraga. It is all Aluminium construction, supported inside with SS rods.
He sent me following pics
Regards
Sachin
He sent me following pics
Regards
Sachin
Yes heatsinks are anodized in Black color. Cab anodizing and faceplate is pending.
Regards
Sachin
Regards
Sachin