dear sir
greetings every one at diy i am a new member but under
moderation iwanted to know if anyone has constructed quasar
1000 watts @4 ohms i made legend stsage master 500 watt @ 8 OHMS
HAD NO PROBLEMS GOOd sound easy to make now ready to make
quasar as suggested by maibasicradan location bajaluka and victor
1986 does any PCB pattern exists wanting some feedback on sound
quality power any special tips while assembling it hope any one can
help me
andrew lebon
agra india
greetings every one at diy i am a new member but under
moderation iwanted to know if anyone has constructed quasar
1000 watts @4 ohms i made legend stsage master 500 watt @ 8 OHMS
HAD NO PROBLEMS GOOd sound easy to make now ready to make
quasar as suggested by maibasicradan location bajaluka and victor
1986 does any PCB pattern exists wanting some feedback on sound
quality power any special tips while assembling it hope any one can
help me
andrew lebon
agra india
Quasor is very good. no problem
You will need IRFP240 bee same(5%) just like MJE15034-35,
attention offset <10mV and bias 30mA
You will need IRFP240 bee same(5%) just like MJE15034-35,
attention offset <10mV and bias 30mA
Quasor is the closest jagodic has gotten to the original
doug self "blameless" design.
I built the BJT version of this and it is the most transparent
amp one could imagine, most distortions are nearly
immeasurable unless you have 5000$ test equiptment.
A most rewarding project that will dazzle you with its
sound and is more refined than the quasi NMOS amps.
doug self "blameless" design.
I built the BJT version of this and it is the most transparent
amp one could imagine, most distortions are nearly
immeasurable unless you have 5000$ test equiptment.
A most rewarding project that will dazzle you with its
sound and is more refined than the quasi NMOS amps.
Thank you "ostripper" for nice oppinion about amp. It is very clasic topology and according to Radan, it is performing excelent.
One correction: name of that design is QUASOR and not QUASAR!
One correction: name of that design is QUASOR and not QUASAR!
Hey, Boraomega, one question .., why the irf510 for VBe??
I,ve never seen fet used for this.
I use the standard BD139 VBE, but I use BJT OPS.
The only mods other than that I use LED or precision voltage
source IC with buffer for CCS and mine runs on +-60V
without the cascode. But it sounds MUCH better than
junk sony or JVC amps and I get 150W/250W 8/4 ohm.
Very reliable circuit tolerant of most mods..😀 😀
I,ve never seen fet used for this.
I use the standard BD139 VBE, but I use BJT OPS.
The only mods other than that I use LED or precision voltage
source IC with buffer for CCS and mine runs on +-60V
without the cascode. But it sounds MUCH better than
junk sony or JVC amps and I get 150W/250W 8/4 ohm.
Very reliable circuit tolerant of most mods..😀 😀
Well ostripper, I believe you already answered your own question in another topic (power amp under development):
"The one mod that is interesting in the good doctor's design is
the use of FET as the VBE (Thermal coeff same as MOSfet outputs??)"
…which doesn't mean that it is not possible to make equally good thermal bias control with BJT-s in Vbe multiplier.
Each designer has some preferences regarding particular sub-circuits, sometimes justified, sometimes it is just like that...
As CCS sub-circuit I prefer one of those two given on a picture attached to this post. To my taste, both are giving way better results than any LED based version.
"The one mod that is interesting in the good doctor's design is
the use of FET as the VBE (Thermal coeff same as MOSfet outputs??)"
…which doesn't mean that it is not possible to make equally good thermal bias control with BJT-s in Vbe multiplier.
Each designer has some preferences regarding particular sub-circuits, sometimes justified, sometimes it is just like that...
As CCS sub-circuit I prefer one of those two given on a picture attached to this post. To my taste, both are giving way better results than any LED based version.
Attachments
amplifier working
dear sir
greetings everyone especially malbasicradan for the help
made it on stage master mk 2 pcb its working as you said even
posted picture of amplifier ugly but working can you tell me your
biasing techniqe running it on 75 volts dc 60000 mfd on each rail
have made the softstart circuitand dc protection waiting to wind my
torroidal what was your secondary ac voltage
do ultrafast rectifiers give a cleaner sound what type of load do you
use
1 the 15pf circuit diagram shows it connected tobase of mpsa92 and
collector of mje350 but pcb layout shows it connected from output
to drain pin of irf510 WHICH IS CORRECT will be making pcb from
factory near my house will keep you posted
thanking you
andrew lebon
dear sir
greetings everyone especially malbasicradan for the help
made it on stage master mk 2 pcb its working as you said even
posted picture of amplifier ugly but working can you tell me your
biasing techniqe running it on 75 volts dc 60000 mfd on each rail
have made the softstart circuitand dc protection waiting to wind my
torroidal what was your secondary ac voltage
do ultrafast rectifiers give a cleaner sound what type of load do you
use
1 the 15pf circuit diagram shows it connected tobase of mpsa92 and
collector of mje350 but pcb layout shows it connected from output
to drain pin of irf510 WHICH IS CORRECT will be making pcb from
factory near my house will keep you posted
thanking you
andrew lebon
15pf need to be conect to base mpsa 92 and collector mje 350 is corect soryyyyy!
Becouse my english is not so good I dont understand what you say with this( can you tell me your
biasing techniqe running it on 75 volts dc 60000 mfd on each rail
have made the softstart circuitand dc protection waiting to wind my
torroidal what was your secondary ac voltage),please tell me!?
Becouse my english is not so good I dont understand what you say with this( can you tell me your
biasing techniqe running it on 75 volts dc 60000 mfd on each rail
have made the softstart circuitand dc protection waiting to wind my
torroidal what was your secondary ac voltage),please tell me!?
quasar supply
dear sir
thanks for the prompt reply i wanted to ask you
1 transformer secondary voltage
2 for what do you use it outdoor sound what type of speakers do
you use
3
heat sink used its size
canyou post a picture of it on diy
how did you bias your amplifier bias setting
thanking you
andrew lebon
dear sir
thanks for the prompt reply i wanted to ask you
1 transformer secondary voltage
2 for what do you use it outdoor sound what type of speakers do
you use
3
heat sink used its size
canyou post a picture of it on diy
how did you bias your amplifier bias setting
thanking you
andrew lebon
quasar diyers
hi everyone
good to see interest in quasar 1000 watt how many diy
are making it can share tips with you all like soft start dc protector
tone controls etc
thanking you all
andrew lebon
hi everyone
good to see interest in quasar 1000 watt how many diy
are making it can share tips with you all like soft start dc protector
tone controls etc
thanking you all
andrew lebon
Building Quasar 1000Watt
Hi All,
I am busy building a Quasar amp. Will post pics later. I am almost finished with the amp. Still waiting for my transformer before I can test the amp. It is close to festive season and everything is am bit slow now. Andrew can you please share your DC protector and softstart circuit with us. I would really appretiate this. Thanks😎 😎 😎
Macd
Hi All,
I am busy building a Quasar amp. Will post pics later. I am almost finished with the amp. Still waiting for my transformer before I can test the amp. It is close to festive season and everything is am bit slow now. Andrew can you please share your DC protector and softstart circuit with us. I would really appretiate this. Thanks😎 😎 😎
Macd
reply
hi macd
good to know you are making the amp did you match the
mosfets well tomorrow i will e mail u the dc protector and soft start
will help u if u need mosfet matcher schematic please i u can post
pictures of your amp bye
andrew lebon
hi macd
good to know you are making the amp did you match the
mosfets well tomorrow i will e mail u the dc protector and soft start
will help u if u need mosfet matcher schematic please i u can post
pictures of your amp bye
andrew lebon
reply
hi black
greetings well u asked for pictures i did not have any pcb
so i built on dr boras stage master mk 2 pcb added 2 small pcb
and made it work picture is on dx turbo page of destroyer he was kind
en
ough to post it will be getting pcbs made then i will redo the amp
hi black
greetings well u asked for pictures i did not have any pcb
so i built on dr boras stage master mk 2 pcb added 2 small pcb
and made it work picture is on dx turbo page of destroyer he was kind
en
ough to post it will be getting pcbs made then i will redo the amp
dc protector surge limiter
hi macd
greetings the dc protector is from edwin paij website only
replace bc 550 bc560 with bc 547 and bc557 if bc550 bc560 is not
available it has a pcb layout very compact circuit works component
easily available surge limiter for transformer is from krell ksa50 clone
amplifier in the circuit diagram use top part of circuit 18 0 18 volt
transformer 1000 mf condenser.015 condenser2.2k 1watt 220k 100mf condenser for time delay mpsa 56 tr and irf 610 tr for operating the relay for mains resistance use 25 ohms 20 watt relay 24 volts dc can
be made on small veroboard do not use relay 2 as shown in circuit
if not happy can e mail u more circuits
thanking you
andrew
hi macd
greetings the dc protector is from edwin paij website only
replace bc 550 bc560 with bc 547 and bc557 if bc550 bc560 is not
available it has a pcb layout very compact circuit works component
easily available surge limiter for transformer is from krell ksa50 clone
amplifier in the circuit diagram use top part of circuit 18 0 18 volt
transformer 1000 mf condenser.015 condenser2.2k 1watt 220k 100mf condenser for time delay mpsa 56 tr and irf 610 tr for operating the relay for mains resistance use 25 ohms 20 watt relay 24 volts dc can
be made on small veroboard do not use relay 2 as shown in circuit
if not happy can e mail u more circuits
thanking you
andrew
- Status
- Not open for further replies.