SOUND POST CRACK ~:-|

bassiszen · #1 10-08-2010, 09:23 PM

I own a very nice carved Chinese bass. I've had it about three years, and I'm the first owner. I paid about 10K for it. It has rarely left my place.

Anyway, I recently discovered a crack and came to realize that I have a wonderful sound post crack in the back. I took it to a very reputable luthier for a diagnosis, and was informed that it was going to cost a lot of money to fix it. I almost **** myself.

Has anyone ever encountered this sort of problem before? What does it usually stem from?

Thanks

Jake deVilliers · #2 10-09-2010, 12:00 AM

Bummer! I'm not sure there's a 'usual' cause, but often its the ribs shrinking and the soundpost staying the same length that's the problem.

New basses should have their posts looked at annually to keep more serious damage from happening. Its a lot easier to trim a soundpost than repair a crack.

I'm sure your bass will turn out well and live a long and happy life!

Good luck, Jake

Matt Ides · #3 10-09-2010, 07:09 AM

Trim the post and put in a patch

arnoldschnitzer · #4 10-09-2010, 07:11 AM

A soundpost crack in the back is usually caused by the bass falling forward onto the bridge. The shock is sent through the soundpost, which then splits the back. It tends to happen more in basses that have a tight soundpost. The permanent repair solution is to remove the back plate, glue up the crack, install an inlaid patch with the grain slightly skewed in relation to the wood of the back, then reinstall the back and fit a new soundpost. That can be very expensive. The less expensive fix is to glue up the crack with the top still attached, then fit a small patch under the soundpost, working through the f-hole. This is a common repair, and can sometimes last as long as the instrument.

bassiszen · #5 10-09-2010, 05:37 PM

Quote:

Originally Posted by arnoldschnitzer

A soundpost crack in the back is usually caused by the bass falling forward onto the bridge. The shock is sent through the soundpost, which then splits the back.

Arnold, Thanks for the information.

The bass never fell forward onto the bridge. Aside from bringing it home, it's only left my house for short stints to the luthier. My other bass takes the brunt of my travels.

When I first noticed the crack I thought it was a scratch in the finish. Very small maybe about an inch. Less than a week later it had doubled in size, and then doubled again. There's even a little rise on the top of the bass where the soundpost sits. Is it possible that the soundpost was too long and that bass shrunk that much in only a few years?

Should I loosen the strings to the point of taking the bridge off?

bassics1975 · #6 10-09-2010, 07:49 PM

A number of situations could lead to such a crack. In many cases, an improperly fitted soundpost could be the culprit but being a newer bass, it is probably just the movement of the wood as it looses moisture in drier climates. I had the same thing happen to a new carved bass one winter. Our climate here could be rough...humid summers and dry winters. I actually found that the instrument spoke better after the fact. Sometimes there is a silver lining to a cloud.

arnoldschnitzer · #7 10-10-2010, 06:08 AM

Quote:

Originally Posted by bassiszen

There's even a little rise on the top of the bass where the soundpost sits. Is it possible that the soundpost was too long and that bass shrunk that much in only a few years?

Should I loosen the strings to the point of taking the bridge off?

Yes, it's possible that the crack was caused by shrinkage, especially if the wood was damp and/or unseasoned when the bass was built. And it may be that the back was carved thin for tone.

Yes, you should take off the bridge and try to push the soundpost over, so the bass can relax.

robobass · #8 10-10-2010, 06:27 AM

10k for a Chinese bass? Is that right?

LHbassist · #9 10-10-2010, 06:47 AM

The origin of your bass was China. You and the bass now live in Rego Park, Queens...an area I'm quite familiar with. I grew up in Woodside, worked fixing guitars at Sam Ash Music in Forest Hills until 1982.
Anyway, In Reno- Lake Tahoe, where I repair basses now, we see huge fluctuations in humidity. It can be as low as 13% in the summer. Yeah, you read right. It is currently 71% humidity in my shop. I repair a LOT of humidity, NOT temperature related cracks. The basses I see usually are cracked somewhere, due to a dramatic change in the humidity, or the ALTITUDE where the bass is stored, versus the area where the bassist uses it. Lake Tahoe is 6,500 feet above sea level, and Reno is 4,420. We seldom see a 2,000 foot difference in altitude from gig to home in N.Y. It is quite common here.
I have to retune my Lowendall carved bass when I play in Truckee, or South Lake Tahoe. I would guess Rego Park is about a hundred feet or so, above sea level- or close to it.
The Chinese factory, or luthier's shop your bass came from, is kept at what humidity? What altitude? We do not know. What kind of drying method do they use for the billets of wood used in the making of their basses?
I have seen an inferior grade defective maple billet used in a hybrid Sunrise bass, but am not familiar with the higher priced Chinese basses. I would say, it is possible that the piece of wood used to carve the top, was not properly acclimated, or suffered a humidity-drying out related crack exacerbated by pressure from the post and the bridge. After arriving here, in The U.S., as it acclimated to the Queens area, things weren't quite the same as in their shop, or geographical area. The post just helped it open up. The top patch, installed from the outside, through the 'F' hole, and reduction in soundpost length is a very stable, strong repair done by a good bass luthier. I've done quite a few, never had one come back. Good luck with your bass!

bassiszen · #10 10-11-2010, 03:04 PM

Quote:

Originally Posted by robobass

10k for a Chinese bass? Is that right?

When I was buying my bass I played almost a dozen of them at varying prices around the price range I was looking for. For the price I paid I couldn't find the quality in craftsmanship and wood in any other basses.

On top of that the sound of the bass has really opened up over the years. Now I just have to deal with an annoying crack, but it could have happened to any bass.

bassiszen · #11 10-11-2010, 03:13 PM

Thanks LHbassit.

Eric Swanson · #12 10-11-2010, 07:43 PM

Do you have any relevant insurance that could help you with the repair costs?

I had a bass that ripped itself apart for a variety of reasons. Long story short; insurance made it all work out.

Good luck, in any event. So sorry to hear about the damage to your bass...it is a bad, bad feeling.