Larrchild
Well-known member
I think we have whats called a "Sarchasm" , Svart.
I was kidding Raff there.
I know my photoshop art is good. I don't need smoke.
Now circuits..thats another kettle of fish. :shock:
CCS and the TUBE
- Thread starter analag
- Start date
Help Support GroupDIY Audio Forum:
I think we have whats called a "Sarchasm" , Svart.
I was kidding Raff there.
I know my photoshop art is good. I don't need smoke.
Now circuits..thats another kettle of fish. :shock:
rafafredd
Well-known member
I´m sorry Larr, but that last one by Winston is the best.
Let´s finally get back to the thread. Anyone ever tried a LM317 as CCS in a tube preamp?
Larrchild
Well-known member
Winston wins by several lengths, no doubt!
Or for more juice, a TV horizontal output bipolar wrapped around a LM317?
CJ
Well-known member
OK, I know a plate resistor makes noise, but isn't a solid state device doing the same thing, being a resistor, that is?
So how is the noise going thru the current source compare with the noise going thru a resistor?
Will it be the same?
Just one aspect of the design, I know.
So how is the noise going thru the current source compare with the noise going thru a resistor?
Will it be the same?
Just one aspect of the design, I know.
Winston OBoogie
Well-known member
OK, "CCS and the TUBE" it is then.
What's the objective?
I'm not against any circuit topology if it's clearly better, or at least significantly cheaper yet not necessarily magnitudes worse, than other alternatives.
Arguably, one of the better sounding CCS circuits is the one linked to below from G. Pimm:
http://home.pacifier.com/~gpimm/self_bias_ccs.gif
However, sometimes I can't hear much difference between that circuit and a 10M45S.
I'm currently diggin' using a CCS to feed local regulators. The idea came from reading Lynn Olson's site. Here's a circuit example of his:
http://www.nutshellhifi.com/IT-Triode-Amp.gif
Gotta go and sleep for a couple of hours.
Wasn't dissin' yer circuit Rowan, just playing around after working too many hours. Sorry if it offended, none meant.
Edit 1: Like your RCA art Larr :grin: :thumb:
Edit 2: Would just like to drag NY Dave's name into this one more time... :roll:
What's the objective?
I'm not against any circuit topology if it's clearly better, or at least significantly cheaper yet not necessarily magnitudes worse, than other alternatives.
Arguably, one of the better sounding CCS circuits is the one linked to below from G. Pimm:
http://home.pacifier.com/~gpimm/self_bias_ccs.gif
However, sometimes I can't hear much difference between that circuit and a 10M45S.
I'm currently diggin' using a CCS to feed local regulators. The idea came from reading Lynn Olson's site. Here's a circuit example of his:
http://www.nutshellhifi.com/IT-Triode-Amp.gif
Gotta go and sleep for a couple of hours.
Wasn't dissin' yer circuit Rowan, just playing around after working too many hours. Sorry if it offended, none meant.
Edit 1: Like your RCA art Larr :grin: :thumb:
Edit 2: Would just like to drag NY Dave's name into this one more time... :roll:
pstamler
Well-known member
About that carrot...no, I wasn't kidding. But it's not really a Stamler carrot -- I'm just the reporter. It's a Lansman carrot.
Peace,
Paul
Peace,
Paul
CJ
Well-known member
Yeah, whats so funny about peace, love and understanding, anyway? :?:
rafafredd
Well-known member
Well, he posted a nice schem for discussion, winston talked about a cheesburger just as an example, and it evolved into a "classic graphics thread", as CJ put it. But the graphs used the original analag schem, so he people was making ridiculous of his design. Then everybody made it clear that it was not the intention.
Now it´s up to Analag to accept the apologies (or not) and get back in the forum for discussing CCS and tubes.
I think that´s it.
Now it´s up to Analag to accept the apologies (or not) and get back in the forum for discussing CCS and tubes.
I think that´s it.
Larrchild
Well-known member
What you don't understand, Roger is that analag was going to pull the schematic anyway.
That's what analag does.
We just got it out of the way a whole lot faster, but the fact remains that on at least 2 other occasions, he posts, some wiseguy makes a comment and we spend 3 pages giving him reaffirmation.
No More.
Accept our apology for our hooligan manners, and rejoin the topic we are trying to speak seriously on now.
Personally, I will try to add kielbasi and such to less offendible folk in the future. And it was still funny.
Lar'
That's what analag does.
We just got it out of the way a whole lot faster, but the fact remains that on at least 2 other occasions, he posts, some wiseguy makes a comment and we spend 3 pages giving him reaffirmation.
No More.
Accept our apology for our hooligan manners, and rejoin the topic we are trying to speak seriously on now.
Personally, I will try to add kielbasi and such to less offendible folk in the future. And it was still funny.
Lar'
Larrchild
Well-known member
Im gonna go mark up dave's stuff.
Equal-Time.
Equal-Time.
Larrchild
Well-known member
I'm telling ya, Roger, if someone did that to me, after I cleaned the keyboard of nose-spit, I would try to outdo them somehow and getback on topic by goin "ok guys, as I was saying"
And not be so thin skinned. But everyone's different.
And not be so thin skinned. But everyone's different.
Marik
Well-known member
The advantages of the SS CCS against the coil are obvious--low cost and space, very high and constant load (unlike of coil, which drops at the low end significantly), wide bandwidth, and high power supply rejection.
[quote author="Larrchild"] "ok guys, as I was saying"
[/quote]
OK guys, as I was saying in another thread on the same topic,
I tried both, deplition mode MOSFET DN2540 and current regulator IXP10M45S (which I suspect is a similar device). Both gave me two same problems--about 6db higher noise and occasional "boiling" spikes--the reason I put a coil there, instead (haha! don't start again here, I mean a copper around iron).
This is in agreement with CJ's passage:
So Gentlemen, take your arses off the Photoshop and start talkin' 'bout darn thing.
[quote author="Larrchild"] "ok guys, as I was saying"
[/quote]
OK guys, as I was saying in another thread on the same topic,
I tried both, deplition mode MOSFET DN2540 and current regulator IXP10M45S (which I suspect is a similar device). Both gave me two same problems--about 6db higher noise and occasional "boiling" spikes--the reason I put a coil there, instead (haha! don't start again here, I mean a copper around iron).
This is in agreement with CJ's passage:
So Gentlemen, take your arses off the Photoshop and start talkin' 'bout darn thing.
Winston OBoogie
Well-known member
Roger,
Sorry you missed Rowan's circuit before it was pulled. I do have a copy on my drive but it's not for me to re-post it as it's his circuit. Nor do I think I should give an explaination as to it's workings as, again, it's Rowan's.
I will explain my circuit though which you were kind enough to repost.
1/ The 'potato' is the H.T supply.
2/ This H.T. feeds the cheeseburgers which represent a cascoded pair of devices that are supplying current to the valve. The chocolate eclair supplying some 'turn-on' for them and the 'Winston' pack some bypassing.
3/ This 'Constant Current' arrangement feeds the 'Indian-Rope-Trick' guy who is performing the function of shunt regulator
4/ The role of load on the anode is taken by a hot-dog acting as a resistor.
5/ The biasing for the valve is the newly named 'Lansman carrot'.
6/ Signal from the valve's anode is coupled through a pair of Leyden Jars to different brand hot-dog R.
7/ Heat for the valve is supplied by a blowtorch which may eleviate the need for a L.T. line :wink:
8/ There is a coil/choke/inductor in the grid circuit.
A jocular way of presenting the idea I agree, but a decent idea and use of a CCS nonetheless IMHO. As I posted earlier, similar arrangements have been used to good ends by Lynn Olson.
A couple more links to some interesting reading regarding CCS loads along with a 'hot linked' picture of the Gary Pimm circuit I mentioned earlier which, again, I think is a good one to try:
And the reading:
http://home.pacifier.com/~gpimm/Active_loads_and_signal_current_control.html
http://www7.taosnet.com/f10/mustage.html
http://members.aol.com/sbench/outstru.html
Ciao.
Sorry you missed Rowan's circuit before it was pulled. I do have a copy on my drive but it's not for me to re-post it as it's his circuit. Nor do I think I should give an explaination as to it's workings as, again, it's Rowan's.
I will explain my circuit though which you were kind enough to repost.
1/ The 'potato' is the H.T supply.
2/ This H.T. feeds the cheeseburgers which represent a cascoded pair of devices that are supplying current to the valve. The chocolate eclair supplying some 'turn-on' for them and the 'Winston' pack some bypassing.
3/ This 'Constant Current' arrangement feeds the 'Indian-Rope-Trick' guy who is performing the function of shunt regulator
4/ The role of load on the anode is taken by a hot-dog acting as a resistor.
5/ The biasing for the valve is the newly named 'Lansman carrot'.
6/ Signal from the valve's anode is coupled through a pair of Leyden Jars to different brand hot-dog R.
7/ Heat for the valve is supplied by a blowtorch which may eleviate the need for a L.T. line :wink:
8/ There is a coil/choke/inductor in the grid circuit.
A jocular way of presenting the idea I agree, but a decent idea and use of a CCS nonetheless IMHO. As I posted earlier, similar arrangements have been used to good ends by Lynn Olson.
A couple more links to some interesting reading regarding CCS loads along with a 'hot linked' picture of the Gary Pimm circuit I mentioned earlier which, again, I think is a good one to try:
And the reading:
http://home.pacifier.com/~gpimm/Active_loads_and_signal_current_control.html
http://www7.taosnet.com/f10/mustage.html
http://members.aol.com/sbench/outstru.html
Ciao.
Winston OBoogie
Well-known member
[quote author="Marik"]The advantages of the SS CCS against the coil are obvious--low cost and space, very high and constant load (unlike of coil, which drops at the low end significantly), wide bandwidth, and high power supply rejection.
[/quote]
Cost: after looking at the costs myself, there wasn't really much in it. Providing one knows where to buy, a decent choke can be had for about $15. You also need to allow for the costs of a higher H.T. supply for the solid-state CCS if the same output swing is required.
Higher equivalent load: OK.
Bandwidth: hard one to argue with but I do think there is something very musical about a plain old resistor or choke. It's just an opinion or preference at the end of the day. I try not to put as much weight on specs as on what my gut says.
Power Supply Rejection: how much power supply do we need to reject?
If it's a lot then we should take another look at the supply.
A choke is pretty good at that too.
Anyway, I know you opted for a coil for your current storage device in light of the noise issues but do you remember what the sonic differences betwixt them where - aside from the noise that is?
Ciao.
[/quote]
Cost: after looking at the costs myself, there wasn't really much in it. Providing one knows where to buy, a decent choke can be had for about $15. You also need to allow for the costs of a higher H.T. supply for the solid-state CCS if the same output swing is required.
Higher equivalent load: OK.
Bandwidth: hard one to argue with but I do think there is something very musical about a plain old resistor or choke. It's just an opinion or preference at the end of the day. I try not to put as much weight on specs as on what my gut says.
Power Supply Rejection: how much power supply do we need to reject?
If it's a lot then we should take another look at the supply.
A choke is pretty good at that too.
Anyway, I know you opted for a coil for your current storage device in light of the noise issues but do you remember what the sonic differences betwixt them where - aside from the noise that is?
Ciao.
Marik
Well-known member
Cost: after looking at the costs myself, there wasn't really much in it. Providing one knows where to buy, a decent choke can be had for about $15...
Fair... unless you want to use a low DCR, high inductance, low capacitance choke. I actually tried an expensive Lundahl one and... did not like its sound at all :grin: Ended up with a $10 one. :green:
The other consideration is the size. If you want to squize the thing in 1U, it is quite hard to find one to fit.
...I do think there is something very musical about a plain old resistor or choke.
Agree with the choke. To me resistors have some fuzzy qualities in sound I don't neccessarily like.
Sure, for some applications they might be fine, but since I record classical music only, I am looking for max. transparency and dynamics, which resistors do not have. So just another opinion...
Power Supply Rejection: how much power supply do we need to reject?
If it's a lot then we should take another look at the supply.
A choke is pretty good at that too.
Hard to beat!
However, there is another point--chokes tend to pick hum, so careful orientation and shielding often is essential. In some situations it is impossible, though (for example, I live in an old house, with particularly screwed up wiring, so no shielding helps. For the same reason I cannot use ANY ribbon mics here--only in one place in the house, with certain angle).
Anyway, I know you opted for a coil for your current storage device in light of the noise issues but do you remember what the sonic differences betwixt them where - aside from the noise that is?
Yes,
With SD mics I prefer coil. It is just more musical and rounds edges very nicely.
However, for example, with ribbon mics I would prefer to use a CCS, as it has more clarity, has more defined bass and gives some edge and transparency on the top end.
Fair... unless you want to use a low DCR, high inductance, low capacitance choke. I actually tried an expensive Lundahl one and... did not like its sound at all :grin: Ended up with a $10 one. :green:
The other consideration is the size. If you want to squize the thing in 1U, it is quite hard to find one to fit.
...I do think there is something very musical about a plain old resistor or choke.
Agree with the choke. To me resistors have some fuzzy qualities in sound I don't neccessarily like.
Sure, for some applications they might be fine, but since I record classical music only, I am looking for max. transparency and dynamics, which resistors do not have. So just another opinion...
Power Supply Rejection: how much power supply do we need to reject?
If it's a lot then we should take another look at the supply.
A choke is pretty good at that too.
Hard to beat!
However, there is another point--chokes tend to pick hum, so careful orientation and shielding often is essential. In some situations it is impossible, though (for example, I live in an old house, with particularly screwed up wiring, so no shielding helps. For the same reason I cannot use ANY ribbon mics here--only in one place in the house, with certain angle).
Anyway, I know you opted for a coil for your current storage device in light of the noise issues but do you remember what the sonic differences betwixt them where - aside from the noise that is?
Yes,
With SD mics I prefer coil. It is just more musical and rounds edges very nicely.
However, for example, with ribbon mics I would prefer to use a CCS, as it has more clarity, has more defined bass and gives some edge and transparency on the top end.
[quote author="Larrchild"]What you don't understand, Roger is that analag was going to pull the schematic anyway.
That's what analag does.
We just got it out of the way a whole lot faster, but the fact remains that on at least 2 other occasions, he posts, some wiseguy makes a comment and we spend 3 pages giving him reaffirmation.Lar'[/quote]
Classic reverse psychology, my dear friend. Good one.
Take that, before I pull it.
analag
That's what analag does.
We just got it out of the way a whole lot faster, but the fact remains that on at least 2 other occasions, he posts, some wiseguy makes a comment and we spend 3 pages giving him reaffirmation.Lar'[/quote]
Classic reverse psychology, my dear friend. Good one.
Take that, before I pull it.
analag
Adjust the 1K pot until you get 150V at the anode of U2. Adjusting the pot will not affect the current sourcing through the tube, one of the beauties of the CCS.
The PSRR of this circuit is so high, a simple RC type filter network will work just fine. Multiple RC's of course.
Try some carbon film resistors on the plate, next time. Sounds better than metal film.
analag
The PSRR of this circuit is so high, a simple RC type filter network will work just fine. Multiple RC's of course.
Try some carbon film resistors on the plate, next time. Sounds better than metal film.
analag
I have done some bootstrapping on low gain tubes.
The downside is that the cap needs to be driven from a a low Z , so were still gonna need two active devices.
The upside is that it doesnt add any extra noise like a SS active CCS.
Just a thought.
The downside is that the cap needs to be driven from a a low Z , so were still gonna need two active devices.
The upside is that it doesnt add any extra noise like a SS active CCS.
Just a thought.
