Improving bass response after it is built?

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rcnewcomb
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Improving bass response after it is built?

Post by rcnewcomb »

Build #2 has been settling in for about 5 days now. It's a redwood/mahogany dreadnought from a Stewmac kit. Obviously I used a different top.

I've noticed the bass is not nearly as strong as the treble. What are my options?

1. Do I need to give it more time to settle in?
2. Are there some braces that I could/should sand to improve the bass response?
3. Should I just let it be and move on to the next build?
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop
ruby@magpage.com
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Re: Improving bass response after it is built?

Post by ruby@magpage.com »

I don't know, but I recently finished an oak ladder braced 16" guitar with the opposite problem - the bass is much louder than the treble. Can't wait to hear the discussion.

Ed
Ed M
tippie53
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Re: Improving bass response after it is built?

Post by tippie53 »

Do you have any pictures of the bracing or others from when you where building?
Also what style of guitar?
what bracing scheme ?
top wood ?
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ruby@magpage.com
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Re: Improving bass response after it is built?

Post by ruby@magpage.com »

Not trying to hijack, but just give more info for better discussion. This one is bass heavy and a little weak on volume. The details were done with help from Haans Brentrup who specialized in this type of instrument.

Red spruce, sitka bracing, Osage Orange plate:

Ed
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rcnewcomb
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Re: Improving bass response after it is built?

Post by rcnewcomb »

tippie53 wrote:Do you have any pictures of the bracing or others from when you where building?
Also what style of guitar?
what bracing scheme ?
top wood ?
It is the standard StewMac dread brace pattern on a redwood top.
Image
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop
rcnewcomb
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Re: Improving bass response after it is built?

Post by rcnewcomb »

Thinking about this further. Does a thicker top mean less bass?
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop
johnnparchem
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Re: Improving bass response after it is built?

Post by johnnparchem »

Thicker top or taller braces mean less bass. Basically stiffness supports the trebles but hurts the bass. But if I were to try to tune the top at this stage I would work on the braces. When I work on the braces, I try to take a bit from a few areas listening to the top by tapping as I go. If I remove from an area and it sounds better I remove a bit more from the same area. If it makes no difference I go to the next target on my list and follow the same procedure. The order that I use is the tone bar scallops, then knock down the the far peaks of the tone bars, then the near peaks of the tone bars, the x brace scallops and the far xbrace peak. If the top was not already closed I would take a bit from the xbrace cross if the above did not help.
ruby@magpage.com
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Re: Improving bass response after it is built?

Post by ruby@magpage.com »

John

Do you have some electronic equipment or do you listen with your ears to the tap tone. In my experience, I don't have enough exposure to even start thinking about what is "better" - is there some set of rules to follow?

Ed
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johnnparchem
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Re: Improving bass response after it is built?

Post by johnnparchem »

I do both, ears and software. There is a free tool visual analyzer http://www.sillanumsoft.org/ that can show the resonance freaquencies of the guitar. It just needs a PC and almost any microphone. I set up as described in a document by Trevor Gore http://www.goreguitars.com.au/attachmen ... ata_R1.pdf.

What I would be looking is to move the top resonance to around 180 Hz. A bit higher in a small guitar.

One could also listen, in this case the guitar is described as too much treble and lacking bass. What I would look for is to make the pitch of the tap note lower. It is important to not do to much at a time. Make some changes that you think you can hear string it up it see if you are happier.
ruby@magpage.com
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Re: Improving bass response after it is built?

Post by ruby@magpage.com »

Thanks John. I'll give my failing ears a work out on the one I am in the middle of now

Ed
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