Sorry.
The distinction didn't occur to me until you mentioned it, Mouse. I suspect that places me firmly at the baseball bat level of remonstration. My first grade teacher was right, after all.
The distinction didn't occur to me until you mentioned it, Mouse. I suspect that places me firmly at the baseball bat level of remonstration. My first grade teacher was right, after all.
Re: Sorry.
Dear boy, a baseball bat? One would prefer a cricket bat, or possibly if one was of the lower orders, a pickaxe handle...... 😉
Colescuttle said:
Dear boy, a baseball bat? One would prefer a cricket bat, or possibly if one was of the lower orders, a pickaxe handle...... 😉
Help with matching (DUMMY ALERT!)
Everything I'm reading indicates that even when not absolutely necessary matched devices contribute to the stability and sonics of a discrete SS amp circuit. In anticipation of the boards being ready soon I've bought as many transistors as I can find (and afford) and will try to get the best matches possible. I have two questions:
1) My DMM has an Hfe measuring capability. Is there a better, simple, alternate measurement that I could employ? I don't have a variac or any other equipment. If I use Hfe or another approach, what do I look for? In other words, how good a match is a "match?"
2) Which of the following devices get matched with which, in channel and across channels: Q1, Q2, Q3, Q4, Q5, Q7, Q8, Q9, Q12, T1, U3, U4, U5, U6?
Thanks.
Notjusteedumbgeorge
Everything I'm reading indicates that even when not absolutely necessary matched devices contribute to the stability and sonics of a discrete SS amp circuit. In anticipation of the boards being ready soon I've bought as many transistors as I can find (and afford) and will try to get the best matches possible. I have two questions:
1) My DMM has an Hfe measuring capability. Is there a better, simple, alternate measurement that I could employ? I don't have a variac or any other equipment. If I use Hfe or another approach, what do I look for? In other words, how good a match is a "match?"
2) Which of the following devices get matched with which, in channel and across channels: Q1, Q2, Q3, Q4, Q5, Q7, Q8, Q9, Q12, T1, U3, U4, U5, U6?
Thanks.
Notjusteedumbgeorge
Hi Colescuttle,
Look at the design on both Pavel's and Mike's web pages. They go through all of that. The same information is spread out in these threads.
Just click on the "www" under each member to get to their sites.
-Chris
Look at the design on both Pavel's and Mike's web pages. They go through all of that. The same information is spread out in these threads.
Just click on the "www" under each member to get to their sites.
-Chris
Ohter transistors
Hi there,
I have a pair of 2SA1216/2SC2922 power and 2SA968/2SC2238 driver transistors laying around. Would these be usable in the AAK symasym, or are these too fast at 50MHz ft as compared to 30 MHz for the 5200/1943.
Is there anyone who can advise about possible changes to the feedback network?
Thanks
Rick
Hi there,
I have a pair of 2SA1216/2SC2922 power and 2SA968/2SC2238 driver transistors laying around. Would these be usable in the AAK symasym, or are these too fast at 50MHz ft as compared to 30 MHz for the 5200/1943.
Is there anyone who can advise about possible changes to the feedback network?
Thanks
Rick
Re: Ohter transistors
Hi Rick, these transistors shouldn't be a problem... 2SA1216/2SC2922 has already been used in symasym without problems.
Mike
Rick NL said:
Hi Rick, these transistors shouldn't be a problem... 2SA1216/2SC2922 has already been used in symasym without problems.
Mike
Hi all,
to keep the discussions focused I started a "Symasym AAK model builder's thread" for all technical questions such as parts substitutions, and variations in values between Mike's original and AAK's suggestions. This is especially for those who ordered the AAK designed PCB in the recent group buy.
Symasym AAK builder's thread
I compiled the variances of resistor values between the circuits, and questions to it, in
post number 10
to keep the discussions focused I started a "Symasym AAK model builder's thread" for all technical questions such as parts substitutions, and variations in values between Mike's original and AAK's suggestions. This is especially for those who ordered the AAK designed PCB in the recent group buy.
Symasym AAK builder's thread
I compiled the variances of resistor values between the circuits, and questions to it, in
post number 10
Anyone other than me...
... considering trying regulated supply for the just the front and VAS stages?
... considering trying regulated supply for the just the front and VAS stages?
Nothing yet..
My last amp project was repairing an Exposure integrated. I was surprised there are regulation not just on the pre but the power amp too. After repairing, I like the way the amp sounded.
The onboard supply designed into the AAK Symasym pcb should ensure the output stage have quick access to juice when it needs it so I'm thinking of removing the 22r at the rails and fit regulation for the low level stages.
Reading up on a few options at the moment. I would appreciate a few suggestions or is this a crazy idea and not worth the complication?
Looked up regulation on Self's and JLH's books but not much there.
As you know Ake I have ordered the AAK boards.
Meantime, I'm dreaming of cases, trafo and whatifs...
My last amp project was repairing an Exposure integrated. I was surprised there are regulation not just on the pre but the power amp too. After repairing, I like the way the amp sounded.
The onboard supply designed into the AAK Symasym pcb should ensure the output stage have quick access to juice when it needs it so I'm thinking of removing the 22r at the rails and fit regulation for the low level stages.
Reading up on a few options at the moment. I would appreciate a few suggestions or is this a crazy idea and not worth the complication?
Looked up regulation on Self's and JLH's books but not much there.
As you know Ake I have ordered the AAK boards.
Meantime, I'm dreaming of cases, trafo and whatifs...
Hi cromodora,
Symasym's combination of front end filtering, and low psrr is more than enough. Regulating the front end would only complicates things without any added benefits IMO.
Best regards,
Al
Symasym's combination of front end filtering, and low psrr is more than enough. Regulating the front end would only complicates things without any added benefits IMO.
Best regards,
Al
The output transistors 2sc5200-OQ/2sa1943-OQ Are there any bennfits sonical to use them compared to MJL21193/94 or MJL1302/MJL3281?I have lots of them.
🙂
🙂
It depends on your taste, the MJL21193/4 sound very lovely, tubish like, the MJL3281/1302 sound very clear/hard, the SC5200/SA1943 very soft but clean. My Favourite is MJL0281/0302 (or MJW), they sound crystal clear and clean but no sign of hard sound.
Mike
Mike
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