Samson C03 capsule
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The Samson C03 that I've got here (it was very cheap) has two of what they claim are 19mm capsules back-to-back - nearly an inch apart. The size claim they make for the capsule is ridiculous if you look closely though - the diaphragm is about 14mm, and there's a phase compensator around the outside. And these are back-electret capsules, not 'proper' externally polarised ones.
Or is your Samson C03 different?
Or is your Samson C03 different?
Junk
I have two CO1s I cut the capsule apart it is a realy cheap design IMO. I have changed parts in the CO1 trying to make it better. I could not get rid of the hiss. The electronics are not bad the capsule is the weak spot. The capsule has high noise IMO.
I have two CO1s I cut the capsule apart it is a realy cheap design IMO. I have changed parts in the CO1 trying to make it better. I could not get rid of the hiss. The electronics are not bad the capsule is the weak spot. The capsule has high noise IMO.
They changed the electronics in the C03 completely - it sounds better than the C01 (and yes, that is two C01 capsules in a C03), but it's still not good. 'Junk' is a very appropriate word to describe them.
What I thought might be a good idea was to remove any reference at all to 'Samson' from the body (which is the best part of it), and put some rather better innards in. The body is diecast, and there's not a staggeringly large amount of room in there, but I would have thought that with some care, a 1" capsule and some solid state electronics would fit. Dunno about a tranny, though...
What I thought might be a good idea was to remove any reference at all to 'Samson' from the body (which is the best part of it), and put some rather better innards in. The body is diecast, and there's not a staggeringly large amount of room in there, but I would have thought that with some care, a 1" capsule and some solid state electronics would fit. Dunno about a tranny, though...
clintrubber
Well-known member
:shock: Oops, surprised to hear that the '03 uses back electret as well.
from SOS:
http://www.soundonsound.com/sos/nov03/articles/samsonc03.htm?session=946b3857abf5d993feeaa6e368ceecfa
Hmm, SOS-info isn't what it used to be... there's a place of course for BE, but it's good to see that the Lab-people reveal the real facts...
Bye,
Peter
Well, this sucks... 68 bucks down the crapper! 
Isn't that false advertisement? Go to Samsons website and there's nothing anywhere that says it's an electret capsule... Not even in the C03 manual!!!
This is the stuff lawsuits are made of!!! :twisted:
Peace,
Al.
Isn't that false advertisement? Go to Samsons website and there's nothing anywhere that says it's an electret capsule... Not even in the C03 manual!!!
This is the stuff lawsuits are made of!!! :twisted:
Peace,
Al.
Interesting to see a double-cardioid wired 3-way.
> surprised to hear that the '03 uses back electret as well.
Nothing horribly wrong with back electret. Voltage is voltage. And if you don't want to pay for the good stuff (high electret voltage in thin film), the back-plate is the place for the electret.
High hiss suggests they didn't bother with a proper grid (gate) resistor, but rely on leakage to keep the gate near ground. People who hack the Panasonic capsules sometimes add a 100MegΩ or more gate resistor. Is that the FET that I'm seeing in the C03 picture you posted? Since Gus has tried upgrading the rest without success, maybe time to hack that.
It can still be just a cheap capsule. Bad choice of size, spacing, voltage, and damping. Fixing basic flaws would be more trouble than making your own, or finding a better cheap capsule.
Hmmmm... a 2-capsule double-cardioid may need massive equalization to be flat in all 3 patterns. And that's a likely place for big hiss. But assuming they are basically flat cardioid capsules, cardioid is probably just one capsule, little or no EQ. Omni should be both, and no EQ. Only bi-di would have huge cancellation, all in the bass. It might rumble, not what you'd call hiss.
I swear the housing around the capsule looks like the capsule mount from some $6 headphones I've found trashed.
> surprised to hear that the '03 uses back electret as well.
Nothing horribly wrong with back electret. Voltage is voltage. And if you don't want to pay for the good stuff (high electret voltage in thin film), the back-plate is the place for the electret.
High hiss suggests they didn't bother with a proper grid (gate) resistor, but rely on leakage to keep the gate near ground. People who hack the Panasonic capsules sometimes add a 100MegΩ or more gate resistor. Is that the FET that I'm seeing in the C03 picture you posted? Since Gus has tried upgrading the rest without success, maybe time to hack that.
It can still be just a cheap capsule. Bad choice of size, spacing, voltage, and damping. Fixing basic flaws would be more trouble than making your own, or finding a better cheap capsule.
Hmmmm... a 2-capsule double-cardioid may need massive equalization to be flat in all 3 patterns. And that's a likely place for big hiss. But assuming they are basically flat cardioid capsules, cardioid is probably just one capsule, little or no EQ. Omni should be both, and no EQ. Only bi-di would have huge cancellation, all in the bass. It might rumble, not what you'd call hiss.
I swear the housing around the capsule looks like the capsule mount from some $6 headphones I've found trashed.
clintrubber
Well-known member
Sure, fully agree. The surprising part just being that people still don't get the free lunch they were thought to be getting.
Also surprised to see those two capsules so far removed from each other - for some reason I understood it to be necessary/better/... these needed to be closer - otherwise 'frequency implications' would happen.
Thought to have read some article addressing this issue but can't remember where - and all this is before my first coffee so I'm not really capable yet to derive the probably obvious implications of that spacing myself right now. :wink:
Bye,
Peter
Yeah, that mounting is weird. I would have expected the capsules to be mounted with the diaphragms in the same plane; maybe the phase compensaors are supposed to correct for that.
That does look like an FET peeking out there. Maybe replacing the FETs and using a couple nice gigohm bias resistors would be a good first step in rehabilitating these puppies.
That does look like an FET peeking out there. Maybe replacing the FETs and using a couple nice gigohm bias resistors would be a good first step in rehabilitating these puppies.
[quote author="PRR"]
High hiss suggests they didn't bother with a proper grid (gate) resistor, but rely on leakage to keep the gate near ground. People who hack the Panasonic capsules sometimes add a 100MegΩ or more gate resistor. Is that the FET that I'm seeing in the C03 picture you posted? Since Gus has tried upgrading the rest without success, maybe time to hack that. [/quote]
The electronics in the C01 and the C03 are completely different. The black bits you can see in the C03 (okay, it's not the best pic in the world) are bits of plastic that the capsule mounting bolts screw into. You might like the next bit - each capsule has its own impedance converter, and this appears to be a surface-mount TL072. The capsules are connected directly to the non-inverting inputs, with a 1Gohm bias resistor. The pattern changing appears to take place with the aid of a HEF4066BT CMOS switch hanging directly from the outputs of the 072. Neat? (don't answer that question...)
The C01 has a much simpler, and more conventional FET input. I've changed the FET for a lower noise one, and played around with the bias resistor (yes it has one), and managed to improve the noise by a measly 0.5dB when the capsule is connected. Let's face it - it's a noisy capsule, for whatever reason.
The electrical noise from each capsule/impedance converter is effectively uncorrelated - and appears to add into the output whatever pattern you select.
[quote author="yan_b"]how do you take off the grill?[/quote]
You don't need to - when you have removed the diecast body, there are four screws in the top of the internal framework that hold the screen over the capsules - remove these and the top will come off. If you unplug the blue LED connector, the top is completely removable.
High hiss suggests they didn't bother with a proper grid (gate) resistor, but rely on leakage to keep the gate near ground. People who hack the Panasonic capsules sometimes add a 100MegΩ or more gate resistor. Is that the FET that I'm seeing in the C03 picture you posted? Since Gus has tried upgrading the rest without success, maybe time to hack that. [/quote]
The electronics in the C01 and the C03 are completely different. The black bits you can see in the C03 (okay, it's not the best pic in the world) are bits of plastic that the capsule mounting bolts screw into. You might like the next bit - each capsule has its own impedance converter, and this appears to be a surface-mount TL072. The capsules are connected directly to the non-inverting inputs, with a 1Gohm bias resistor. The pattern changing appears to take place with the aid of a HEF4066BT CMOS switch hanging directly from the outputs of the 072. Neat? (don't answer that question...)
The C01 has a much simpler, and more conventional FET input. I've changed the FET for a lower noise one, and played around with the bias resistor (yes it has one), and managed to improve the noise by a measly 0.5dB when the capsule is connected. Let's face it - it's a noisy capsule, for whatever reason.
This is simply two of the C01 cardiod capsules mounted back-to-back about 1" apart. If you add the outputs, you get an omni response, and if you subtract them, then you get a figure-8. The problem with the arrangement acoustically is that there will be cancellations in the figure-8 response where the wavelength is the same as the distance between the diaphragms - which I've now measure to be about 20mm. So, taking the velocity of sound to be 330m/s, we'd have a cancellation frequency of 330/0.02 = 16.5kHz. It's clear that the screen with holes in it surrounding each capsule will alter the front to back path length at different frequencies, but without plotting the response of the capsule with and without it present, it's not easy to even guess at what it is contributing.
The electrical noise from each capsule/impedance converter is effectively uncorrelated - and appears to add into the output whatever pattern you select.
That would be about it - it's effectively a plastic post mounted in a rubber moulding that has virtually no resiliance at all at low frequencies, considering the relatively low weight of the capsules. They may as well have mounted the capsules solidly onto the body of the mic for all the difference this makes to transmitted rumble pickup.
[quote author="yan_b"]how do you take off the grill?[/quote]
You don't need to - when you have removed the diecast body, there are four screws in the top of the internal framework that hold the screen over the capsules - remove these and the top will come off. If you unplug the blue LED connector, the top is completely removable.
[quote author="clintrubber"]
from SOS:
http://www.soundonsound.com/sos/nov03/articles/samsonc03.htm?session=946b3857abf5d993feeaa6e368ceecfa
Hmm, SOS-info isn't what it used to be... there's a place of course for BE, but it's good to see that the Lab-people reveal the real facts...
[/quote]
Yes... I have spoken to Paul White about this. He's cross, to say the least, and was going to have 'words' with Samson. His take on this is that he can't dismantle a mic when he gets it for review, and that he is completely in their hands, especially in cases like this when a piece of black foam is placed inside the grille, obscuring what's really in there completely.
If you read what Samson say in their advertising, technically the only sin they commit is to suggest that this is a 19mm capsule - which it absolutely isn't - it's about 14mm. All of their other sins are sins of omission. Yes, they are pulling a flanker on unsuspecting punters, and unwittingly Paul White has helped them. The other thing he said to me, in an attempt to justify the situation by other means (which you might find surprising in view of my comments about the impedance converter, and what follows it, above) is that "it sounded so much better than the C01".
Now, I don't trust his ears, either!
from SOS:
http://www.soundonsound.com/sos/nov03/articles/samsonc03.htm?session=946b3857abf5d993feeaa6e368ceecfa
Hmm, SOS-info isn't what it used to be... there's a place of course for BE, but it's good to see that the Lab-people reveal the real facts...
[/quote]
Yes... I have spoken to Paul White about this. He's cross, to say the least, and was going to have 'words' with Samson. His take on this is that he can't dismantle a mic when he gets it for review, and that he is completely in their hands, especially in cases like this when a piece of black foam is placed inside the grille, obscuring what's really in there completely.
If you read what Samson say in their advertising, technically the only sin they commit is to suggest that this is a 19mm capsule - which it absolutely isn't - it's about 14mm. All of their other sins are sins of omission. Yes, they are pulling a flanker on unsuspecting punters, and unwittingly Paul White has helped them. The other thing he said to me, in an attempt to justify the situation by other means (which you might find surprising in view of my comments about the impedance converter, and what follows it, above) is that "it sounded so much better than the C01".
Now, I don't trust his ears, either!
The CO1 circuit is like the standard china copy of the schopes(sp) as best I can tell. 500meg grid to ground. The electronics are OK it is the capsule. I think the capsule is to restrictive with it air paths. The AT4033 I have sound way better and have lower noise as well. the 4033s are back electret SD 2 micron.
The co1 capsule is just a capsule. The fet is on the PCB and is a b105 IIRC. The capsule is a pressed together thing without any electronics in it.
I believe the CO3 is something like one of the CAD microphones. I think Lomo made a tube microphone that had two circuits inside mixed for patterns. One half of the capsule to a seperate tube circuit.
The co1 capsule is just a capsule. The fet is on the PCB and is a b105 IIRC. The capsule is a pressed together thing without any electronics in it.
I believe the CO3 is something like one of the CAD microphones. I think Lomo made a tube microphone that had two circuits inside mixed for patterns. One half of the capsule to a seperate tube circuit.
That's pretty a shocking looking microphone :shock: but they are cheap.
[Getting off topic slightly, but following on from Gus's comments above, I have been thinking about building a (tube) mic with seperate outputs for front and back capsules so that you can effectively make a recording, and then decide on the polarity pattern at the mix-down stage. Could be fun.]
I think listening tests are so subjective and I don't really trust anyone's ears anymore.
[Getting off topic slightly, but following on from Gus's comments above, I have been thinking about building a (tube) mic with seperate outputs for front and back capsules so that you can effectively make a recording, and then decide on the polarity pattern at the mix-down stage. Could be fun.]
clintrubber
Well-known member
from Steve:
I can very well imagine the problems that reviewers face - especially when manufacturers play tricks to create certain impressions. When in doubt about certain things, some questions for verifying would have helped, but you can't cover everything.
Point is of course that manufacturers kind of 'have' to play this game.
I mean, it's not good, but since we've all become so informed by all available www-info & such, I figure that at least some part of our opinions will be based on what we read i.s.o. hands-on experience.
Put another way, it'll be a fact that there will be people out there who (have to) base their opinions (well, at least their impressions) entirely on what they've read.
This isn't strange - at least speaking for myself I can say I haven't tried
solid state at 120V AND all kinds of electrolytics AND various kinds of
transformer-brands AND pentodes-as-triodes vs triodes etc etc.
Only 24 hours a day, so I (like everybody else) have impressions about certain subjects and they might very well be incorrect (as far as the the objective side of all this goes).
So despite that we know that back-electrets are not the total evil (I even understood some well respected mics happen to BE's, probably the mentioned AT's), manufacturers realize the bad rap and go to great lenghts to hide that a mic is a BE.
Same story could for instance be told about for starved plate stuff:
a piece of gear is advertised as having a 'genuine 12AX7'
but you don't get told on which voltage it runs.
While I have some starved plate stuff that (in this specific case) to my ears sounds better than some other stuff that runs on HT, generally speaking I guess we can agree that starved plate is cheaper in cost & sound.
So manufacturers realize they need to hide that it's running on the rectified heater voltage.
This all is totally in line with Kev's story of a while back: if you suggest to a customer that a certain cool looking piece of gear is inserted in the signal path and you turn a dial, the sound gets indeed better -while
the unit may not be inserted at all of even be a totally empty box with a few fake controls (I thought his story went somewhere along these lines).
So at least a considerable part of the people who have money to spend in this field can be misled.
And/or have ideas or opinions not based on that hands-on experience. So it's important they don't pass by your product because they've read that it can't be any good because it uses a certain kind of topology or technique.
Enough rambling, sorry, bye, over & out,
Peter
I can very well imagine the problems that reviewers face - especially when manufacturers play tricks to create certain impressions. When in doubt about certain things, some questions for verifying would have helped, but you can't cover everything.
Point is of course that manufacturers kind of 'have' to play this game.
I mean, it's not good, but since we've all become so informed by all available www-info & such, I figure that at least some part of our opinions will be based on what we read i.s.o. hands-on experience.
Put another way, it'll be a fact that there will be people out there who (have to) base their opinions (well, at least their impressions) entirely on what they've read.
This isn't strange - at least speaking for myself I can say I haven't tried
solid state at 120V AND all kinds of electrolytics AND various kinds of
transformer-brands AND pentodes-as-triodes vs triodes etc etc.
Only 24 hours a day, so I (like everybody else) have impressions about certain subjects and they might very well be incorrect (as far as the the objective side of all this goes).
So despite that we know that back-electrets are not the total evil (I even understood some well respected mics happen to BE's, probably the mentioned AT's), manufacturers realize the bad rap and go to great lenghts to hide that a mic is a BE.
Same story could for instance be told about for starved plate stuff:
a piece of gear is advertised as having a 'genuine 12AX7'
but you don't get told on which voltage it runs.
While I have some starved plate stuff that (in this specific case) to my ears sounds better than some other stuff that runs on HT, generally speaking I guess we can agree that starved plate is cheaper in cost & sound.
So manufacturers realize they need to hide that it's running on the rectified heater voltage.
This all is totally in line with Kev's story of a while back: if you suggest to a customer that a certain cool looking piece of gear is inserted in the signal path and you turn a dial, the sound gets indeed better -while
the unit may not be inserted at all of even be a totally empty box with a few fake controls (I thought his story went somewhere along these lines).
So at least a considerable part of the people who have money to spend in this field can be misled.
And/or have ideas or opinions not based on that hands-on experience. So it's important they don't pass by your product because they've read that it can't be any good because it uses a certain kind of topology or technique.
Enough rambling, sorry, bye, over & out,
Peter
> surprised to see those two capsules so far removed from each other
They are cardioids. You have to leave the back wide-open. If you have to have an obstruction, it should be at least about as far away as it is wide. So a 19mm baffle 20mm away is just as close as can be without severe trouble.
> each capsule has its own impedance converter, and this appears to be a surface-mount TL072. The capsules are connected directly to the non-inverting inputs, with a 1Gohm bias resistor.
I sit corrected. It isn't totally cheap.
But the 072 has quite a high noise voltage. That begs for hackery. A lower-noise JFET-input chip, or a total re-work keeping only the sweet 1G resistor.
It may still be a noisy capsule.
> don't get the free lunch they were thought to be getting.
Golly. Flat across most of the audio band, three patterns, lower noise than many studios, output high enough to overwhelm the noise of any mike input, pretty case, $69-$99!!! :grin: , and you want a free lunch too? :roll: Why not a coffee maker as well? :wink:
It seems to me to be a very nicely designed product. If it were better, it would kill sales of higher-price mikes. Samson and the stores would have to live on the small profit possible in a $69-$99 selling price. That would be a commercial disaster.
They are cardioids. You have to leave the back wide-open. If you have to have an obstruction, it should be at least about as far away as it is wide. So a 19mm baffle 20mm away is just as close as can be without severe trouble.
> each capsule has its own impedance converter, and this appears to be a surface-mount TL072. The capsules are connected directly to the non-inverting inputs, with a 1Gohm bias resistor.
I sit corrected. It isn't totally cheap.
But the 072 has quite a high noise voltage. That begs for hackery. A lower-noise JFET-input chip, or a total re-work keeping only the sweet 1G resistor.
It may still be a noisy capsule.
> don't get the free lunch they were thought to be getting.
Golly. Flat across most of the audio band, three patterns, lower noise than many studios, output high enough to overwhelm the noise of any mike input, pretty case, $69-$99!!! :grin: , and you want a free lunch too? :roll: Why not a coffee maker as well? :wink:
It seems to me to be a very nicely designed product. If it were better, it would kill sales of higher-price mikes. Samson and the stores would have to live on the small profit possible in a $69-$99 selling price.
That would be a commercial disaster.Marik
Well-known member
[quote author="SmG"]The Samson C03 that I've got here (it was very cheap) has two of what they claim are 19mm capsules back-to-back - nearly an inch apart. The size claim they make for the capsule is ridiculous if you look closely though - the diaphragm is about 14mm, and there's a phase compensator around the outside. And these are back-electret capsules, not 'proper' externally polarised ones.
http://www.garnett-associates.pwp.blueyonder.co.uk/Samson/Image1.jpg
[/quote]
Are you sure it is a back electret? Looking at the pics it seems that they might use generic SD capsule used in ML603, etc. and put a housing around, as a phase correction. Two high Z resistors on another pic might suggest it, as well.
Can you take the capsules from the housing and post pics?
http://www.garnett-associates.pwp.blueyonder.co.uk/Samson/Image1.jpg
[/quote]
Are you sure it is a back electret? Looking at the pics it seems that they might use generic SD capsule used in ML603, etc. and put a housing around, as a phase correction. Two high Z resistors on another pic might suggest it, as well.
Can you take the capsules from the housing and post pics?
[quote author="clintrubber"]
Enough rambling, sorry
[/quote]
No apology necessary - it was all very much to the point, really. I'll confess that when offered the C03 very cheaply, I bought it knowing full well at that stage what was in a C01 - and in the full knowledge that I could well end up using the diecast body and grille - which really are the best parts of the mic - to house something rather better. And never mind comparing the C01 and C03 - when I compare either of them directly to the 'proper' large-diaphragm mics I have, it's like chalk and cheese - as you would expect.
But there is too much stuff about for everybody to be able to compare everything, to be sure - and this allows unscrupulous manufacturers to get away with all sorts of things, I suspect, especially when the reviews are going to be primarily subjective, and not subject to proper measurement scrutiny. But having looked at a couple of SOS mic reviews since the ill-fated C03 one, I've noticed that at least one has been shown disassembled - so maybe I've effected a slight change for the better - I don't know. I'd like to hope so, though. Paul White strikes me as being a sincere guy, though, which is why I mentioned it to him privately, rather than as an open letter to the magazine. He also has an electronics background, so he was quite intrigued by what I'd discovered inside anyway. Yes, he's seen the pictures.
[quote author="PRR"]or a total re-work keeping only the sweet 1G resistor. [/quote]
Oops, I forgot. The only other useful part.
Enough rambling, sorry
[/quote]
No apology necessary - it was all very much to the point, really. I'll confess that when offered the C03 very cheaply, I bought it knowing full well at that stage what was in a C01 - and in the full knowledge that I could well end up using the diecast body and grille - which really are the best parts of the mic - to house something rather better. And never mind comparing the C01 and C03 - when I compare either of them directly to the 'proper' large-diaphragm mics I have, it's like chalk and cheese - as you would expect.
But there is too much stuff about for everybody to be able to compare everything, to be sure - and this allows unscrupulous manufacturers to get away with all sorts of things, I suspect, especially when the reviews are going to be primarily subjective, and not subject to proper measurement scrutiny. But having looked at a couple of SOS mic reviews since the ill-fated C03 one, I've noticed that at least one has been shown disassembled - so maybe I've effected a slight change for the better - I don't know. I'd like to hope so, though. Paul White strikes me as being a sincere guy, though, which is why I mentioned it to him privately, rather than as an open letter to the magazine. He also has an electronics background, so he was quite intrigued by what I'd discovered inside anyway. Yes, he's seen the pictures.
[quote author="PRR"]or a total re-work keeping only the sweet 1G resistor. [/quote]
Oops, I forgot. The only other useful part.
Erm, it will be two noisy capsules, so 3dB higher in omni and figure-8.
