Why are string bows so hairy?
All violin bows I have seen are designed to hold a width of at least 1cm of hair. However, in my string training, I was always taught to rotate the bow so that only the outer-most hairs contact the strings. So what is all the other hair for? I imagine the answer is either:
- The extra hair serves only to support the tension of the bow. Or,
- My training is incorrect, and there are times when it is correct to press the bow flat against the strings so they are engaged by the full width of bow hair.
(To elaborate on my training: In my youth I had a decade of classical violin lessons. Revisiting violin technique now I realize that I was always trained to rotate the bow so that only the outer-most hairs (i.e., those opposite my thumb on the bow hand) make contact with the strings. I was taught to modulate bow speed and bow distance from the bridge in order to control volume. The only time it was correct to attack, "pronate," or otherwise press the bow against the strings with more force so that more hair contacted them, was to get the bow to bounce or skip; and in such a case the purpose was to effect a rebound, not to engage the string with more hair. Indeed: intentionally pulling the bow with all hairs flattened across a string seems to only produce a more muddy, scratchy tone.)
orchestral-strings bow archeterie
asked 8 hours ago
feetwetfeetwet
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feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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All violin bows I have seen are designed to hold a width of at least 1cm of hair. However, in my string training, I was always taught to rotate the bow so that only the outer-most hairs contact the strings. So what is all the other hair for? I imagine the answer is either:
- The extra hair serves only to support the tension of the bow. Or,
- My training is incorrect, and there are times when it is correct to press the bow flat against the strings so they are engaged by the full width of bow hair.
(To elaborate on my training: In my youth I had a decade of classical violin lessons. Revisiting violin technique now I realize that I was always trained to rotate the bow so that only the outer-most hairs (i.e., those opposite my thumb on the bow hand) make contact with the strings. I was taught to modulate bow speed and bow distance from the bridge in order to control volume. The only time it was correct to attack, "pronate," or otherwise press the bow against the strings with more force so that more hair contacted them, was to get the bow to bounce or skip; and in such a case the purpose was to effect a rebound, not to engage the string with more hair. Indeed: intentionally pulling the bow with all hairs flattened across a string seems to only produce a more muddy, scratchy tone.)
orchestral-strings bow archeterie
asked 8 hours ago
feetwetfeetwet
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
All violin bows I have seen are designed to hold a width of at least 1cm of hair. However, in my string training, I was always taught to rotate the bow so that only the outer-most hairs contact the strings. So what is all the other hair for? I imagine the answer is either:
- The extra hair serves only to support the tension of the bow. Or,
- My training is incorrect, and there are times when it is correct to press the bow flat against the strings so they are engaged by the full width of bow hair.
(To elaborate on my training: In my youth I had a decade of classical violin lessons. Revisiting violin technique now I realize that I was always trained to rotate the bow so that only the outer-most hairs (i.e., those opposite my thumb on the bow hand) make contact with the strings. I was taught to modulate bow speed and bow distance from the bridge in order to control volume. The only time it was correct to attack, "pronate," or otherwise press the bow against the strings with more force so that more hair contacted them, was to get the bow to bounce or skip; and in such a case the purpose was to effect a rebound, not to engage the string with more hair. Indeed: intentionally pulling the bow with all hairs flattened across a string seems to only produce a more muddy, scratchy tone.)
orchestral-strings bow archeterie
asked 8 hours ago
feetwetfeetwet
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
All violin bows I have seen are designed to hold a width of at least 1cm of hair. However, in my string training, I was always taught to rotate the bow so that only the outer-most hairs contact the strings. So what is all the other hair for? I imagine the answer is either:
- The extra hair serves only to support the tension of the bow. Or,
- My training is incorrect, and there are times when it is correct to press the bow flat against the strings so they are engaged by the full width of bow hair.
(To elaborate on my training: In my youth I had a decade of classical violin lessons. Revisiting violin technique now I realize that I was always trained to rotate the bow so that only the outer-most hairs (i.e., those opposite my thumb on the bow hand) make contact with the strings. I was taught to modulate bow speed and bow distance from the bridge in order to control volume. The only time it was correct to attack, "pronate," or otherwise press the bow against the strings with more force so that more hair contacted them, was to get the bow to bounce or skip; and in such a case the purpose was to effect a rebound, not to engage the string with more hair. Indeed: intentionally pulling the bow with all hairs flattened across a string seems to only produce a more muddy, scratchy tone.)
orchestral-strings bow archeterie
orchestral-strings bow archeterie
asked 8 hours ago
feetwetfeetwet
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 hours ago
feetwetfeetwet
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 hours ago
feetwetfeetwet
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 8 hours ago
feetwetfeetwet
23010
asked 8 hours ago
feetwetfeetwet
23010
23010
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
feetwet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
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Even if you angle the bow quite strongly, the entire breadth of hair does touch the string as soon as you put some pressure on the bow (the outermost hairs will get stretched and give way, i.e. the bow sinks deeper and the other hairs touch the string too. Only at very low pressure, i.e. very low dynamic level, is it really only the outermost hairs that touch the string. That's probably the idea behind this whole angling thing: to allow pianissimo to be even gentler, while still having all those other hairs for louder passages.
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
|
show 1 more comment
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1 Answer
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Even if you angle the bow quite strongly, the entire breadth of hair does touch the string as soon as you put some pressure on the bow (the outermost hairs will get stretched and give way, i.e. the bow sinks deeper and the other hairs touch the string too. Only at very low pressure, i.e. very low dynamic level, is it really only the outermost hairs that touch the string. That's probably the idea behind this whole angling thing: to allow pianissimo to be even gentler, while still having all those other hairs for louder passages.
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
|
show 1 more comment
Even if you angle the bow quite strongly, the entire breadth of hair does touch the string as soon as you put some pressure on the bow (the outermost hairs will get stretched and give way, i.e. the bow sinks deeper and the other hairs touch the string too. Only at very low pressure, i.e. very low dynamic level, is it really only the outermost hairs that touch the string. That's probably the idea behind this whole angling thing: to allow pianissimo to be even gentler, while still having all those other hairs for louder passages.
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
|
show 1 more comment
Even if you angle the bow quite strongly, the entire breadth of hair does touch the string as soon as you put some pressure on the bow (the outermost hairs will get stretched and give way, i.e. the bow sinks deeper and the other hairs touch the string too. Only at very low pressure, i.e. very low dynamic level, is it really only the outermost hairs that touch the string. That's probably the idea behind this whole angling thing: to allow pianissimo to be even gentler, while still having all those other hairs for louder passages.
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
Even if you angle the bow quite strongly, the entire breadth of hair does touch the string as soon as you put some pressure on the bow (the outermost hairs will get stretched and give way, i.e. the bow sinks deeper and the other hairs touch the string too. Only at very low pressure, i.e. very low dynamic level, is it really only the outermost hairs that touch the string. That's probably the idea behind this whole angling thing: to allow pianissimo to be even gentler, while still having all those other hairs for louder passages.
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
answered 8 hours ago
leftaroundaboutleftaroundabout
19.4k3484
19.4k3484
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
|
show 1 more comment
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Also, sometimes the bow isn't angled and sometimes you reverse the angle, meaning you are primarily loading the hairs on the other side of the bow.
– Todd Wilcox
8 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
Yes, some pressure puts more of the hair in contact, but even when I put the maximum pressure I would use for a sustained note on my bows I see less than half of the hairs engaging the string, and because of the angle the "contact patch" is even narrower. (Granted, I prefer very stiff bows.) Importantly: You seem to be refuting one of the conclusions I drew from (limited, unrecorded) experimentation on my own instrument – in particular, do you assert that drawing more hair across the string at the same pressure (and speed, and rosin) produces louder sound? Not just scratchier sound?
– feetwet
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
@feetwet More hairs at the same pressure&speed does not seem to make it louder, that's true; but more hairs allow you to put more pressure in before the vibration stalls. So, in effect, more hairs do allow you to play louder, because more forceful.
– leftaroundabout
7 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
That makes sense. But only because I know the feeling and have experienced the effect of "stall pressure" – which, if it's not a formal term of art, should be! It suggests the existence of a theoretically rigorous "physics of stringed instruments" that incorporates the dynamics of bowing. I know extensive physics cover acoustics, harmonics, and easily models "struck" strings. Is there comparable science for "bowed" strings that goes to this level of detail?
– feetwet
6 hours ago
1
1
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
@feetwet I think it's pretty simple: to excite and sustain string oscillation, a hair of the bow must have enough pressure so when the string is moving in direction of the bowing, it will stay “stuck” on the rosin, yet not so much pressure that it prevents the string from slipping the same distance back with the lower dynamic friction coefficient. If you double the number of hairs, each hair takes up only have as much pressure, i.e. you can double the total force on the bow and still each of the hairs is in its “non-stalling range”.
– leftaroundabout
6 hours ago
|
show 1 more comment
feetwet is a new contributor. Be nice, and check out our Code of Conduct.
feetwet is a new contributor. Be nice, and check out our Code of Conduct.
feetwet is a new contributor. Be nice, and check out our Code of Conduct.
feetwet is a new contributor. Be nice, and check out our Code of Conduct.
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