then 73Vdc rail to rail was stating only half the voltage on your amplifier.
-/+75vDC, +-75Vdc & 73Vdc-0 -73Vdc are quite clear/unambiguous, all three work.
It was the "rail to rail" that caused the confusion.
-/+75vDC, +-75Vdc & 73Vdc-0 -73Vdc are quite clear/unambiguous, all three work.
It was the "rail to rail" that caused the confusion.
So is it safe for 2SC5200 and 2SA1943 to run on that supply voltage? so far my amp not smoking yet, it sounding good.
You need to look at the temperature de-rated SOAR for a capacitive/inductive loading.
post1471 said
If you have lot's of money, then this is a good method, better than all the simulations can ever predict.
post1471 said
It seems that your method is "does it smoke?"But have you looked at and evaluated the HV SOA of these devices?
If you have lot's of money, then this is a good method, better than all the simulations can ever predict.
I don't have money, that's the reason why I'm using the said device because it's cheaper than the suggested one.
I'm not an engineer AndrewT but I can build an amp.
I'm not an engineer AndrewT but I can build an amp.
Junie,
If you already have the boards and are willing to build a very
ROBUST power supply please buy On Semi or equivalent output devices. This design if properly built will last several DECADES. This is one of the most important places to spend money. The outputs do a lot of work and get hot if driven hard. Also, use a very good insulator under the transistor. Heat transfer is imperative. It will only hurt once in the initial buy.
Most of my ten output amps are running 75 to 85 volt rails. They never get hot. I have the bias set at 1 amp per rail with the fuse removed and my meter across the gap as discussed in the Marshall Leach website. Others use different methods to achieve bias, I chose to use this method. As I dialed up the bias the bass just came alive. I use a small screwdriver with a long wooden handle taped to it to keep me out of the live stuff when adjusting the pot. I also was careful to flow the solder to both sides of the board. Some of the devices have contact on the front/back and others on both sides. The frontend is very congested. Layout your build so you can solder the components without too much stress.
Tad
If you already have the boards and are willing to build a very
ROBUST power supply please buy On Semi or equivalent output devices. This design if properly built will last several DECADES. This is one of the most important places to spend money. The outputs do a lot of work and get hot if driven hard. Also, use a very good insulator under the transistor. Heat transfer is imperative. It will only hurt once in the initial buy.
Most of my ten output amps are running 75 to 85 volt rails. They never get hot. I have the bias set at 1 amp per rail with the fuse removed and my meter across the gap as discussed in the Marshall Leach website. Others use different methods to achieve bias, I chose to use this method. As I dialed up the bias the bass just came alive. I use a small screwdriver with a long wooden handle taped to it to keep me out of the live stuff when adjusting the pot. I also was careful to flow the solder to both sides of the board. Some of the devices have contact on the front/back and others on both sides. The frontend is very congested. Layout your build so you can solder the components without too much stress.
Tad
Mr. Junie What Mr. Tryonziess has stated He,s correct. This is a great amp, and if you need some extra trannies just let me know. Evette
Pcb's
Hi All, I've just picked up on this thread am I too late to buy some 10 transistor Leach pcb's or does anyone on the forum know where I can buy them.
Ian
Hi All, I've just picked up on this thread am I too late to buy some 10 transistor Leach pcb's or does anyone on the forum know where I can buy them.
Ian
Been a long time since I've been on here. Hi to any I've missed.
Anyway, I recall drilling and tapping heatseanks for this very amp. It was at that time I realized I had an injury and could go no further. A couple years (!) later when I was feeling better I found new interests.
I just unearthed a box in the garage. Within is a set of partially completed Leach 10 transistor boards, A nice Mark Levinson (by powertronix) fully potted transformer, the heatsinks I was going to use, and some ON outputs new in the tube (got to through them)
I have no intententions to finish this and was going to stick the whole thing on ebay - but figured I'd pop in here first. Any interest?
Anyway, I recall drilling and tapping heatseanks for this very amp. It was at that time I realized I had an injury and could go no further. A couple years (!) later when I was feeling better I found new interests.
I just unearthed a box in the garage. Within is a set of partially completed Leach 10 transistor boards, A nice Mark Levinson (by powertronix) fully potted transformer, the heatsinks I was going to use, and some ON outputs new in the tube (got to through them)
I have no intententions to finish this and was going to stick the whole thing on ebay - but figured I'd pop in here first. Any interest?
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