give me a couple more weeks and I will look into the options for different PCBs.... Frans has kindly agreed that we can offer his shunt regulator as a separate PCB, so that may be an interesting option for many other builds too...
Thanks RollE2k! I already have the PCB and heatsinks from a friend who did not have the courage to complete the build, but Farnell do not stock all the parts I am looking for. Where to go for better caps and resistors?
Farnell do stock wyelvin 0.1% IMO bit more melow than IRC I tried.
IRC resistor I tried came to about £160
Ask Simon as he did listen to it if is worth it
IMO a few Zfoils around the RIAA may do prety well (not tried so far)
worth the effort? yes as long as one also matches left and right and positive and negative sides
Farnell do stock wyelvin 0.1% IMO bit more melow than IRC I tried.
IRC resistor I tried came to about £160
Ask Simon as he did listen to it if is worth it
IMO a few Zfoils around the RIAA may do prety well (not tried so far)
worth the effort? yes as long as one also matches left and right and positive and negative sides
I have built with all 0.1% parts from Farnell and Mouser. Mix of Vishay and Welwyn. Bought BC327/337's from SOS but watch out for their minimum order.
Val
I think matching is more profitable instead of using expensive, exotic parts.
Hence why using 0.1% resistors - the IRC isn't that expensive either. Also as the cartridge loading the matching isn't that important 1% is more than enough.
The biggest problem with Paradise i think is getting the transistors tightly matched - and i think that is where most people will have their "bottleneck" in this amp. Will start hfe matching my 300+300 transistors myself today, hopefully that will be enough.
By the way, just took a test of 10pcs of 337-transistors and they were all quite high hfe = 500-590 (most around 550), if i would get oscillation later with these transistors because of high hfe - is the caps below the pcb the fix or would it be better buying Another batch?
Have anybody built with high-hfe input stage?
Have anybody built with high-hfe input stage?
By the way, just took a test of 10pcs of 337-transistors and they were all quite high hfe = 500-590 (most around 550), if i would get oscillation later with these transistors because of high hfe - is the caps below the pcb the fix or would it be better buying Another batch?
Have anybody built with high-hfe input stage?
From which brand did you get these high hfe parts??
Thanks..
no they all work
that was just speculation by hesener that high hfe at the input can lead to oszillation
that was never proved in praxis
high hfe at the input has the theoretical advantage that less base current flows into the cartridge
since the paradise boards have input offset trim that red herring is from the table too
that was just speculation by hesener that high hfe at the input can lead to oszillation
that was never proved in praxis
high hfe at the input has the theoretical advantage that less base current flows into the cartridge
since the paradise boards have input offset trim that red herring is from the table too
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what is important for low output offset is thermal coupling of the input transistors
i never had that problem because my build is in a case
many build right in the open and than it matters
the easiest way is to put the input transistors into a paper matchbox other methods have being shown
i never had that problem because my build is in a case
many build right in the open and than it matters
the easiest way is to put the input transistors into a paper matchbox other methods have being shown
From which brand did you get these high hfe parts??
Thanks..
Bought already in May (haven't had time too look at them until now) from mouser.. its these parts:
BC33740BU Fairchild Semiconductor | Mouser
BC32740BU Fairchild Semiconductor | Mouser
Will start matching tomorrow!
Btw, they were almost half the price in May!
By the way - when matching with the circuit in the guide, i always see the voltage (mV) rising slowly while having the multimeter over the parallell 1K resistors, even and backs when removing the multimeter. i take it the value from the start is the value i want, and that the multimeter in some way makes the the voltage rise during measuring?
Bought already in May (haven't had time too look at them until now) from mouser.. its these parts:
BC33740BU Fairchild Semiconductor | Mouser
BC32740BU Fairchild Semiconductor | Mouser
Will start matching tomorrow!
Btw, they were almost half the price in May!
Did you ever tested them if they have ferrus leads??
It is interesting for me to know..
I bought the Fairchild TA part from Mouser and it had magnetic leads..
Thanks..
Did you ever tested them if they have ferrus leads??
It is interesting for me to know..
I bought the Fairchild TA part from Mouser and it had magnetic leads..
Thanks..
Hello!
I checked now - they are magnetical - is this really a big deal?
Regards,
Robert
Hello!
I checked now - they are magnetical - is this really a big deal?
Regards,
Robert
I`m afraid to admit that anything ferrus within the circuit will impose it`s signature on the sound..
Experts say that even the chasis of the instrument,if it`s magnetic will degrade the sound...
I think there must be a better part for the paradise then the BC327/337 .
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