Double Bass I have a soundpost question...(not involving "drilling a hole in the top".)

[TroyK]

Such speculation is in no way forbidden. Only answering so that this not-so-subtle insinuation that the DB moderators are forbidding people to reply to a topic is answered directly. Just to be clear: Not liking a moderator's opinion, voicing your dislike for it, then having a moderator reply they don't want to discuss the disagreement further does not a forbidden topic make.

Right. Keep in mind we are members and moderators and we were the former before we were the later.

As a moderator, there are a variety of ways to prevent, warn, or penalize people for the way they choose to participate. No such actions were taken in that other discussion, though you're acting like they were.

That other topic had been opined upon by players and luthiers and I had spent an hour or so researching the topic and shared my conclusions. You did zero research on your own, but kept replying with "why are you being so closed minded?" What I said was that if you had a point to make that contradicted mine or James's it should be based on something.

Let's bring it here. Why don't you take the sound post out of your bass, bring the strings up to tension, play it for
an hour and report back?

I'll wait right here, but stop asking me to prove that bigfoot isn't real.

If you want to troll me across discussions, the distinction between participating as a member and participating as a moderator might become more apparent to you.

 

[Ryan in PDX]

The picture in my previous post is of the sides and top, with the two bass bars (which in mandolins are known tone bars) on the top; it is an F-style mandolin. The asymmetry is partially due to the style of this mandolin, but can also be somewhat defined by the builder as it relates to tone. The tone bars pictured in the previous post are referred to as parallel tone bars, even though they aren't technically parallel. Tone bars can also be integrated with bracing of the top (ie: X-bracing as shown in the A-style mandolin below).

View attachment 5400164

An interesting point is that arch top mandolins, with 8 or sometimes more high tension strings, have a large amount of pressure on the tops. The tone bars and other bracing methods help spread that tension over the top so the whole top vibrates, and also so the likelihood of top collapse is reduced. "Typically" a carved top mandolin will not have a sound post, although to rescue a collapsing top I have occasionally seen people insert a sound post.

Cool stuff, thanks again. I think I'd best leave this luthiery stuff to you wizards.

 

[GretschWretch]

As for the cat, I loved that cat! He was a prince among felines.

I grieve for the loss of your cat; I'm sorry he is no longer present tense. I have had cats all my life, but just before COVID I lost what I figured would be may last cat. But ten days after my retirement a one year-old female broke into my kitchen at 2:00 am, found no food but stuck around anyway, and she's never left. She's a wonderful animal, as close to a perfect cat as I've ever come.

 

[Don Hergert]

Yay for cats. We need a cats thread!!!

 

[Chris Fitzgerald]

I grieve for the loss of your cat; I'm sorry he is no longer present tense. I have had cats all my life, but just before COVID I lost what I figured would be may last cat. But ten days after my retirement a one year-old female broke into my kitchen at 2:00 am, found no food but stuck around anyway, and she's never left. She's a wonderful animal, as close to a perfect cat as I've ever come.

Beautiful story. We currently have two girls, one old, one young. Both lovable goobers. A house is not a home without lovable critters!

 

[1st Bass]

This was my little buddy, Gadget: always running to meet me when I came home from work...and always ready to inspect my lutherie work.

Sadly, a larger predator (coyote) made a midnight snack of him.
:-(

 

[Bar Star]

With two mods active in this thread, I would have thought that the “Cat Pics and Stories” thread would have been spun off on its own by now…

 

[GretschWretch]

This was my little buddy, Gadget: always running to meet me when I came home from work...and always ready to inspect my lutherie work.
View attachment 5400593

Sadly, a larger predator (coyote) made a midnight snack of him.
:-(

I think I lost one to a coyote as well. But she was a flame-point Siamese, and white cats start to lose their hearing as they age. Yours looks to be a Russian Blue.

 

[GretschWretch]

With two mods active in this thread, I would have thought that the “Cat Pics and Stories” thread would have been spun off on its own by now…

Well, I'll take the blame for keeping this one going. I'm #1 in the Exquisite/Glarry/Burning Fire Club, and we're notorious for being undisciplined and letting things fly wildly out of control in threads; loose constructionists and generalists in the extreme. I think by now the moderators have given up on us and try to just ignore us.

 

[GretschWretch]

Beautiful story. We currently have two girls, one old, one young. Both lovable goobers. A house is not a home without lovable critters!

But a home is not complete without a house possum.

 

[TroyK]

Pets are always on-topic, especially ones with lutherie chops.

 

[Bar Star]

That’s an un-sub for me. Good talk.

 

[Don Hergert]

We currently have 6 cats and one little dog who thinks he's a cat too. One of the cats is around 13 years old, the others and our little dog are about 11 years old. The dog and cats grew up together, all adoptees either off the street or given to us in owner-distress situations when our two sons were still kids and living at home. Our sons are moved out now, leaving us with the pets; we used to have 10 cats when our sons originally moved out (all adoptees), but age and disease has taken some from us. We of course love them all dearly.

Our morning care routine is pretty busy -- I'm in charge of the feedings, watering, walking the dog and I share the cat box cleanings with my wife. We're pretty meticulous about it all; in our early cat experiences we lost a few to cars and coyotes, so if we adopt a cat, it's an indoor cat for the rest of its life, and we keep them very tidy. I've actually learned how to herd cats. Plus our oldest cat has a thyroid problem so I also medicate him 2 times a day; his health is more brittle so we watch him more carefully.

When our sons were kids at home, about 11 years ago one of them brought home a beautiful stray Siamese, one of the most loving cats we've ever had. She was pregnant and presented us with 5 kittens: 3 Snowshoe Siamese, a gray tabby, and a tux. We adopted out one of the Snowshoes (with deep regrets among the kids), but couldn't part with the rest of them. They and the mom are 5 of our 6 cats now. The other cat, our oldest, is a Manx that our band's fiddler couldn't keep; he's one of the smartest cats we've ever seen. They are all pretty cohesive and get along remarkably well.

Of course it is horribly tough to loose a pet, and we're looking at a time when that's going to happen to all of ours. I used to wish that they would outlive us, but honestly it would be more traumatic for them if they lost us, so one of our main jobs in our old age -- we're going on 70 now -- is to outlive them so we can continue giving them living, and when that sad time comes, end of life care. We have a history of having cats live to be 15 to 20 years here, so we have to take care of ourselves too.

We are cat people, yes. But we do have a little dog too.

Access Port CATvantage

• Don Hergert
• Oct 14, 2018
• alcoa trapdoor

 

[Mark_T]

Meet Svend, one of 3 current cats. My bridge looks a little off kilter but I promise it’s fine now. I think it’s partially the angle.

 

[TroyK]

Nice work, Svend.

 

[Tmjohnson62]

Thanks, James. This link was helpful. (Quickly read. Soundposts appear in "violins" in the 15th century, in archtop instruments with greater downforce than "flat" top gizmos.

So, I still am curious if the soundpost was first a "prescriptive" solution to reinforce the (collapsing?) arched top plates, that later BECAME refined and manipulated to become a "tone function"?
It seems counter-intuitive to me, for a double bass esp., to dampen the resonant chamber of the whole corpus by inserting a stick that reduces the vibrations of both the top and back plates, IF you consider the ribs being similar to a drum's shell, and the front and back acting like drum "heads"...freely resonating, and sympathetically vibrating.
I would love to (someday!) $ubsidize the construction of a double bass with NO soundpost, BUT, with 2 Bassbars, (both E & G sides of the bridge feet), and see if the ribs then act as the coupling mechanism between the top and back, thus creating a "non-soundposted" body/corpus, that can withstand the downforce of the strings, and operate as a freely-resonating chamber, similar to a drum. I wonder what that would sound like?
Now, I must go out and purchase a s***load of Lottery tickets.
Fingers crossed.
Thanks for your time and expertise, James.

 

[Tmjohnson62]

I trust over past months you have trashed this thought. Violin and gamba family instruments have a bass bar and a sound post for 3 simple, intuitive reasons. Principles have been understood since long before 1500. A tall bridge causes pressure to soundboard, which will deform and/ or collapse w/o both. The bass bar and bridge work in concert to preventive. The post is essential to tie top vibrations with back. The bar facilitates transfer of vibration to the upper and lower bouts.

Finally, any person ~ musician, luthier recognizes instantly 'something' is amiss hearing a violin or gamba w/o post. The sound is just like pounding a cardboard box pizz or bowing one arco.
Matthew @ String Theory Violins

 

[turf3]

...Violin and gamba family instruments have a bass bar and a sound post for 3 simple, intuitive reasons. Principles have been understood since long before 1500. A tall bridge causes pressure to soundboard, which will deform and/ or collapse w/o both. The bass bar and bridge work in concert to preventive. The post is essential to tie top vibrations with back. The bar facilitates transfer of vibration to the upper and lower bouts.

Finally, any person ~ musician, luthier recognizes instantly 'something' is amiss hearing a violin or gamba w/o post. The sound is just like pounding a cardboard box pizz or bowing one arco.
Matthew @ String Theory Violins

The question however is not "what does a violin family instrument, designed for soundpost/bassbar, sound like if you take the post out?" The question is "can you design a violin family instrument without a post, using instead bracing attached to the top plate to resist string forces, an instrument that would sound good and not collapse?" And the other question would be "what if instead of one bar brace and one post, you had two posts and no bar brace [not two posts AND a bar brace]?"

I'm not sure anyone has answered either question specifically here, though James Condino's post may have addressed these questions.

It's obvious that the soundpost provides a direct link from top plate to back, to help excite the back plate; but at the same time it increases the stiffness of the whole thing which MIGHT reduce the overall ability of the box and enclosed air to resonate.

We see the examples of archtop guitars and mandolins which do not use soundposts, relying instead on top plate bracing (which is more complex than the violin family's single bar), and we see the violin family and gambas which also have arched plates and do use soundposts.

It's hard to imagine that in the 500 years of violin family history no one ever tried either option - no post, two posts. I don't mean for special purposes like mitigating feedback in a heavily amplified performance, I mean for a general purpose instrument. What we don't have, however, is the results of such experiments.

 

[Don Hergert]

I can add this much from my own experience as resulting theories...

Even as strange and sturdy as an Alcoa is, its arched design is nearly identical to that of a standard double bass and along with neck and end blocks, it has both a bass bar and a sound post. My particular Alcoa was used under normal string tension without a sound post long enough that the top acquired a sheet metal tear most of the way from the treble side F-hole to the treble side bridge foot. I gather it didn't happen immediately, but generally my Alcoa was thrashed -- the top repair is only one of quite a few major repairs that had to be made on my Alcoa before it was stable and playable again.

To me based on having seen the extreme top repairs that had to be made on my Alcoa, it is pretty clear that a major reason for the sound post in a double bass is to keep the top from failing. Even though I use low tension synthetic strings, I would never have my repaired Alcoa under concert pitch string tension without a sound post.

As implied earlier in this thread, I also play a couple of mandolins, both which are styled after a 1920s F-style mandolin, with a build design which has a carved arched top and back, with neck and end blocks and tone bars, but with no sound post. Though this is considered a trusted design, tops do occasionally fail and collapse with this kind of mandolin, and ironically, one of the possible quick and dirty solutions is to insert a sound post.

While this type of mandolin's arched design provides significant support for 8 high tension strings, the sound chamber is extremely small compared to the size-scale of of a double bass, or for that matter, that of a cello.

With these arched mandolins, there also are device attachments available for the back of the instrument to allow the back to vibrate freely instead of being deadened by the chest of the player. General consensus is that these devices noticeably improve the tone, volume and clarity of the instrument. It would also seem that on violins and violas the chin rest and shoulder rest do the same thing.

As many of you know, I also play banjo. These are very different stringed instruments from a carved mandolin or viol-family instrument, but they do have one thing in common: a very active sound board. My experience with a variety of banjos is that if they have a back, it is primarily to create an open space for echo tone to proceed outside of the instrument. The backs of these instruments are in constant contact with the torso of the player, so they don't contribute to tone or volume by vibration. Around 90% of the volume of a banjo comes directly off the front of the head.

I would also suggest that considering that a double bass in standing playing posture involves the upper bout resting against the player's body, and that sitting playing posture also usually has the back of the double bass resting against the player's knee, it would seem that having the sides and back of the instrument vibrating freely during play is not a major sound creating concern.

Better minds than mine have tackled this question, and we have here in TB/DB some true experts whose opinions I'd be honored to learn from...

But at this point to me the role of the sound post for a double bass seems to be primarily to support the top. I'm sure it transmits some vibrations to the back, as we can feel it doing so especially when playing in a sitting position, but given the deadening of the instrument against the body of a player, and also given the frequency range of the double bass, I doubt we can hear much if any of the sound contribution that the vibrating back makes. Going further, I'd also suggest that moving the sound post to achieve different tone qualities of a double bass is conceptually the same as moving a very effective mute from one very sensitive top location to another.

 

[Tmjohnson62]