Andrew
652 posts
Oct 05, 2009
3:12 AM
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We need to make this thing explicit. There have been hints about it in the past, but...
Maybe we need to post a drawing so the principle can be understood: -
A reed chamber has two holes (for the two reeds), the draw hole and the blow hole. When you draw, air is sucked in via both these routes - the draw hole, the reed of which vibrates and that blow hole, the reed of which doesn't, because of the way it's configured. (and when you blow, air escapes in the same two directions, with the reeds swapping their behaviour)
No imagined gap between comb and plate is going to be as big as that second hole! If your harp is "leaky" it's because your two reed gaps aren't adjusted as a pair.
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MrVerylongusername
546 posts
Oct 05, 2009
4:01 AM
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...and when you bend, both reeds are vibrating and if there is a gap anywhere around the edge of the comb/plate interface, then you lose compression.
Sorry. Leaky harps are a reality.
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Hobostubs Ashlock
4 posts
Oct 05, 2009
4:35 AM
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I kinda like a little bit of a leaky harp they seem to last longer and can take some abuse if your a rookie like me.just a little leak not a whole lot just a little
Last Edited by on Oct 05, 2009 4:36 AM
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snakes
360 posts
Oct 05, 2009
9:16 AM
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Don't know the physics or mechanical aspect of it, but I do know my user experience. And that is that some harps like Lee Oskar's and Hohner Marine Band take a lot more air for me and seem less responsive and definitely harder to draw bend. I'd love for someone to set me straight on what exactly caused this experience as someday I'd like to get these harps "fixed" because I do like the sound of some of them. ...it is just that they actually impair my playing in their current state. What would you advise Andrew to shore up harps that seem to bend poorly and/or take more air to play (whether wood or plastic comb)?
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sorin
75 posts
Oct 05, 2009
9:39 AM
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snakes ,responsiveness it's got to do with the right gap (first) and slot tolerance .
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nacoran
224 posts
Oct 05, 2009
10:15 AM
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Snakes- Really? I have some complaints about Oskars, but they use the least air of any of my harps. In fact, on a windy day I've held one up outside and it started sounding with no help from me. Of course, this doesn't mean they aren't leaky. Maybe they just have soft bendy reeds?
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ElkRiverHarmonicas
276 posts
Oct 05, 2009
10:31 AM
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If you take a Marine Band and sand the comb perfectly flat, it can make more of a difference than setting gaps, maybe even embossing. Yes, there is probably more air escaping out the opposing reed than between the comb and reedplate - I get your line thought. It makes sense, but, you can't use the total air leakage around the reed in the equation because it cannot be eliminated entirely. You have to have some gap on the other side, even if it's tight, there has to be some space there. Thus, the air loss you have to compare with what leaks around the comb is difference in the air loss between a good gap and a bad one.
Another note: you can gap tighter and still get response when you flatten a comb and eliminate that leakage and if you get a comb perfectly flat, it gets even tighter on the draw, because of the vacuum pulling the plates in even tighter against the comb.
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www.elkriverharmonicas.com
Last Edited by on Oct 05, 2009 10:32 AM
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Hobostubs Ashlock
9 posts
Oct 05, 2009
10:32 AM
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i love Lee Oskars there work horses.I dont know why people dont like them.My 1st good harp was a lee.But then the only hohner ive had been a couple blues benders.I recently got a Seydel solist pro and love it but there harder to find parts for in a hurry i can allways get some reed plates for my lees at the local music store.But then again i also like Huang star performers for the price there not to bad
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snakes
362 posts
Oct 05, 2009
12:30 PM
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nacoran,
Yes I have at least 12 keys of Lee Oskar's as that was the brand I started with and I still use them for Harmonic Minor keys. Virtually all of them take more air than any of the 4 Suzuki models or 3 Seydel models I own. I will say that they are better in that regard than the Marine Bands and Big River I own. I've tried to fall in love with Marine Bands because I love their tone and have purchased 5 or 6 keys, but for the most part they are just hard to play for me. I'll admit to being a cigar smoker with asthma so perhaps my wind is less than most folks. The difference in the playability in Suzuki's and Seydel's compared to the Hohner's and Oskar's is just too noticeable to me to not comment. If I didn't play Suzuki's I'd play Seydel's. They just are that much easier to play for me. I feel what some may perceive as a sacrifice in tone (not me...) with the Suzuki's and Seydel's I more than gain with the ease of playability. For me it is the difference of having to think about getting "set" for certain notes and just playing what I feel naturally.
Last Edited by on Oct 05, 2009 12:32 PM
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MrVerylongusername
548 posts
Oct 05, 2009
12:46 PM
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I think there are two different issues being discussed here. Andrew said no harp is leaky. What he appears to be getting at, and what people here have added is that many out-of the box harps are gapped high. That's easily fixed if you're finding they need too much air.
The issue I was addressing (and Dave Payne has told us how to fix) was the fact that some wooden comb harps come of the production line with saw marks on the comb that make it look like they've been bitten in half by a dog: deep uneven gouges. Others, like one I dealt with a few week ago, have splits where the wood has splintered as the bolts/nails have been driven through. I'm not going to get into a whole this harp vs. that harp debate, but leaky harps are a reality because quality control and cost cutting manufacturing processes can be pretty shoddy. (sometimes)
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oldwailer
908 posts
Oct 05, 2009
1:12 PM
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To say that there is no such thing as a leaky harp is to just not understand what you are saying.
"Leaky" just means that more air is escaping than needs to escape to get the sound and volume you want at a given force.
Leaky harps exist. ONE of the ways to fix them is to adjust the gapping in pairs. Another way is to flatten the comb. Yet another way is to emboss the slots.
Gaps and leaks are not different subjects. . .
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Bluzdude46
219 posts
Oct 05, 2009
1:32 PM
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Ok I just got back and here is a thread with about 4 different topics
1. I know there is "leakage" or what I refer to as leakage because I can feel the air that is not being used by the harp
2 Lee Oskars are not bad harps out of the box. There are actually very consistant. I played them for years. My argument against them is that they didn't hold up well to the abuse that is part of being one of my harps.
3 Others have different issues yet I have had almost no trouble at all with MB combs not being flat
Ok only 3 topics in the thread. My Bad. I missed you guys :::warm & fuzzy emission:::
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jbone
166 posts
Oct 07, 2009
7:57 AM
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ok, one other thing that enters here is checking the reed plate mounting screws and making sure they are snug but not overly tight. one reason i quit buying hering vintage 1923s was they came from the factory with loose screws. but at any rate this is a basic square one thing to check on ANY harp that uses screws to mount the plates to the comb.
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