CL60 vs SL22
Note: Ametherm state these are conservative recommended values to achieve long life
CL60
Resistance at 25C: 10 Ohms
Resistance at Max Current (5A): 180 mOhms
Max steady state current: 5A
Max Energy: 36J
Instantaneous Failure: Not Stated
Diameter: 19.56mm
SL22
Resistance at 25C: 14 Ohms
Resistance at Max Current (5A): 120 mOhms
Max steady state current: 5A
Max Energy: 75J
Instantaneous Failure: 200J
Diameter: 22mm
My dumb brain says SL22 would be quite a bit better than CL60.
Lower in-rush current at 14 Ohms (vs 10 Ohms of CL60)
Significantly higher energy rating of 75J (vs 36J of CL60) and 200J instantaneous.
I'll keep looking around for whats available but I'm not too concerned YET. Hahaha
I have had no issues with CL60 but if there is something better eg SL22, then it makes sense to use it.
Edit: Another option is MS22.
Note: Ametherm state these are conservative recommended values to achieve long life
CL60
Resistance at 25C: 10 Ohms
Resistance at Max Current (5A): 180 mOhms
Max steady state current: 5A
Max Energy: 36J
Instantaneous Failure: Not Stated
Diameter: 19.56mm
SL22
Resistance at 25C: 14 Ohms
Resistance at Max Current (5A): 120 mOhms
Max steady state current: 5A
Max Energy: 75J
Instantaneous Failure: 200J
Diameter: 22mm
My dumb brain says SL22 would be quite a bit better than CL60.
Lower in-rush current at 14 Ohms (vs 10 Ohms of CL60)
Significantly higher energy rating of 75J (vs 36J of CL60) and 200J instantaneous.
I'll keep looking around for whats available but I'm not too concerned YET. Hahaha
I have had no issues with CL60 but if there is something better eg SL22, then it makes sense to use it.
Edit: Another option is MS22.
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Thought this might be helpful for some people. There is a lot to read, I only quoted a small fraction.
Linear Power Supply Design
Major Myth Regarding Capacitance I only heard about this myth recently, and while I can imagine how it came about, it's completely bogus. Some people claim that as the capacitance is increased for a given sized transformer, the peak current is also increased. There are conflicting additional claims that the RMS input current to the transformer either A) does, or B) does not increase as well. Added to this is a further claim that the transformer will overheat because the current is higher.
In essence, this is all complete rubbish. Incorrect measurement techniques or bad simulation practices may lead one to believe that this is the case, but it is not.
Linear Power Supply Design
Major Myth Regarding Capacitance I only heard about this myth recently, and while I can imagine how it came about, it's completely bogus. Some people claim that as the capacitance is increased for a given sized transformer, the peak current is also increased. There are conflicting additional claims that the RMS input current to the transformer either A) does, or B) does not increase as well. Added to this is a further claim that the transformer will overheat because the current is higher.
In essence, this is all complete rubbish. Incorrect measurement techniques or bad simulation practices may lead one to believe that this is the case, but it is not.
Thermistors
I’m currently running with 600,000uf and have a soft start comprising of 4 x thermistors in series (40 ohms cold) with the 1000va transformer primary which are shorted out by a timer relay. That gives about 160v to the transformer which then ramps up to 230v over 5 or so seconds. The thermistors cool down quite quickly when shorted so if I have an issue with the mains power dropping off and then back on momentarily (has happened before) then the supply still soft starts each time.
I’m currently running with 600,000uf and have a soft start comprising of 4 x thermistors in series (40 ohms cold) with the 1000va transformer primary which are shorted out by a timer relay. That gives about 160v to the transformer which then ramps up to 230v over 5 or so seconds. The thermistors cool down quite quickly when shorted so if I have an issue with the mains power dropping off and then back on momentarily (has happened before) then the supply still soft starts each time.
Excellent article of Rod's
I have found over the years that once you have reached a sufficient size cap in the supply, going much bigger tends to change the sound - for example, the Rifa 10mF at 63 volts produces a 'slightly' different sound to the 33mF one in the same supply - using the Siemens/Epcos caps produces a discernable different sound altogether with a similar difference regarding the 2 capacitance sizes.
And using 2 different types of capacitors in a C-R-C type supply can also produce a quite different result (ie 10mF Epcos [ripple], 0.1R, 10mF BHCs [output] - this is especially applicable when it comes to the 'audiophiler' types of caps like the Mundorfs, Nichi, Silmics, SlitFoils, etc rather than the industrial type caps
Curiously, banking up a bunch of 2,2mFs (= 10mF) didn't produce the expected benefits at all - tried this with the Rifa's, Nichicons (GTs) and Silmics, so not an exhaustive example but an indication that a lot of assumptions about the simple power supplies aren't as simple as they seem ...
I do disagree with Rod in the area of diode selection - to me, they make an immediate and obvious difference and the only block bridges I'd ever use are those IXYS Shottky ones - generally I prefer the soft recovery types like the MSRs but in some circumstances, the 'brighter' diodes are more suitable.
Over the years there has been quite a lot of 'heated discussion' about everything to do with power supplies and I don't think there is ever one single power supply design for a specific amplifier as it depends on the individual taste of the builder
I view the amplifier's supply as an active component of the circuit that includes the speakers - the total package, if you will ...
I have found over the years that once you have reached a sufficient size cap in the supply, going much bigger tends to change the sound - for example, the Rifa 10mF at 63 volts produces a 'slightly' different sound to the 33mF one in the same supply - using the Siemens/Epcos caps produces a discernable different sound altogether with a similar difference regarding the 2 capacitance sizes.
And using 2 different types of capacitors in a C-R-C type supply can also produce a quite different result (ie 10mF Epcos [ripple], 0.1R, 10mF BHCs [output] - this is especially applicable when it comes to the 'audiophiler' types of caps like the Mundorfs, Nichi, Silmics, SlitFoils, etc rather than the industrial type caps
Curiously, banking up a bunch of 2,2mFs (= 10mF) didn't produce the expected benefits at all - tried this with the Rifa's, Nichicons (GTs) and Silmics, so not an exhaustive example but an indication that a lot of assumptions about the simple power supplies aren't as simple as they seem ...
I do disagree with Rod in the area of diode selection - to me, they make an immediate and obvious difference and the only block bridges I'd ever use are those IXYS Shottky ones - generally I prefer the soft recovery types like the MSRs but in some circumstances, the 'brighter' diodes are more suitable.
Over the years there has been quite a lot of 'heated discussion' about everything to do with power supplies and I don't think there is ever one single power supply design for a specific amplifier as it depends on the individual taste of the builder
I view the amplifier's supply as an active component of the circuit that includes the speakers - the total package, if you will ...
Which rectifiers are you using. I would like to try them.
I think once you go regulated most things up stream of the regulator are less critical, compared with CRC.
Occasionally Rod has some useful information, but many times he is complaining about a problem that isn't really a problem, you just need to skin the cat differently.
The size of the last cap has quite a significant affect in the output impedance of a CRC supply between 20Hz and 200Hz.
On a regulated supply with feedback, the output impedance is less of a problem.
I'm tending toward zero feedback though. The simulated results are very good. Output impedance is not as low as the feedback version but better than the stock CRC we have grown accustomed too.
I think once you go regulated most things up stream of the regulator are less critical, compared with CRC.
Occasionally Rod has some useful information, but many times he is complaining about a problem that isn't really a problem, you just need to skin the cat differently.
The size of the last cap has quite a significant affect in the output impedance of a CRC supply between 20Hz and 200Hz.
On a regulated supply with feedback, the output impedance is less of a problem.
I'm tending toward zero feedback though. The simulated results are very good. Output impedance is not as low as the feedback version but better than the stock CRC we have grown accustomed too.
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I think once you go regulated most things up stream of the regulator are less critical, compared with CRC.
Yes, I think so too, even with the simple C-Mxs - surprisingly, the Pooge (ALW Audio) and TeddyRegs (Pink Fish Media) seem to transfer the 'raw supply sound' unlike the Super-Regs of Walt Jung, Jan Didden, and derivatives - I used to be quite obsessive about all this, not so much these days.
The size of the last cap has quite a significant affect in the output impedance of a CRC supply between 20Hz and 200Hz.
I think it's not just the size but also the type - there's quite a lot of support for not using electros at all in the output of power supplies - this maybe suitable for lower current circuits but pretty awkward in power amps - I think SIM for reducing Zoutput can be quite misleading but ....
Try the MSR 1560, or 860 - there's a whole family of them out now - those IXYS blocks are pretty okay for me too (not cheap!) and some of the old Phillips BYV's are also quite okay
Yes, I think so too, even with the simple C-Mxs - surprisingly, the Pooge (ALW Audio) and TeddyRegs (Pink Fish Media) seem to transfer the 'raw supply sound' unlike the Super-Regs of Walt Jung, Jan Didden, and derivatives - I used to be quite obsessive about all this, not so much these days.
The size of the last cap has quite a significant affect in the output impedance of a CRC supply between 20Hz and 200Hz.
I think it's not just the size but also the type - there's quite a lot of support for not using electros at all in the output of power supplies - this maybe suitable for lower current circuits but pretty awkward in power amps - I think SIM for reducing Zoutput can be quite misleading but ....
Try the MSR 1560, or 860 - there's a whole family of them out now - those IXYS blocks are pretty okay for me too (not cheap!) and some of the old Phillips BYV's are also quite okay
Try a 100uF poly on the output, if you can physically fit one - the polyesters are okay but still a bit big - the Teddy's use the Tant caps and they work okay - I did try some big Jantzen polypropylenes but just found them slightly better than the MKCs - try some of those Russian K73-16 metal jacket ones or the Epcos B32529 - a nice surprise there.
