How do you find the optimal gap needed for overblowing? Assuming you are able to set up the reed curve so that the blow reed chokes well, you still have three options for the reed gap, it can be too close, too wide or just right.

In order to find the right gap quickly play the overblown note and the blow note repeatedly.
You need to look for a gap where both notes sound equal. When playing the notes one after the other the difference in response will become clear.

Below are three examples.

The first example is played with a gap that is too wide. The blow note will sound long in comparison to the overblown note. The overblown note takes too long before it sounds.

Gap too wide

The second example is played with a gap that is too small. The opposite happens, the blow note sounds short compared to the overblown note and it is slow.

Gap too close

The third example is played with a good gap, both notes sound equal in length and take about the same time to start sounding.

Good gap



User Contributed Notes
24-09-2015 22:30
Thanks for the help Tinus. It's much appreciated.

24-09-2015 21:00
@Gary: Usually when I emboss I also cause the reed to dip at the rivet. You can also push the reed down at the rivet end, then support the first third of the reed (near the rivet) as you bend it back up.
The tip should be as straight as possible for the reed to close the slot when choked.
24-09-2015 20:49
Thanks Tinus i appreciate all your help and the work you've done on this site. It is awesome. How do you get the reed to dip as it go's out of the rivet? When i watched you do it on the video you held the reed and pushed up round about the middle and then you worked at the tip a bit too. With that set you then seemed to push the whole reed down a bit. It's a lot of trial and error i suppose until you get the setting you want. Most times with me the setting is not right as the blow reed does not choke off completely and then you get that weird gargling kind of sound with both things sounding at the same time.

What angle should the tip be set at? Straight with the rest of the reed or does it come up a bit?
24-09-2015 20:03
@Gary: yes changing the curvature of the reed makes a big difference. I always try to dip the reed slightly into the plate at the rivet and then com up very straight from there. The idea is to get the reed to choke completely and suddenly rather then gradually. You have to find that optimum. Try to get the reed set so that it can bend down about a quarter note when isolated and that when it chokes it stops the airflow almost completely. If the reed sort of half chokes but still lets through air it will be very difficult to keep the blowreed still.
22-09-2015 17:39
Hi Tinus, I've tried to set my blow reed on hole 1 nice and tight to the plate but when i get a nice setting for the OB the reed then sticks and the regular hole 1 blow note won't sound, it sticks. Putting it higher cures it of course but then the choking of the blow reed is too hard. I haven't tried arcing yet. Does arcing allow you to have a lower position for the reed without it choking off the regular note?
05-01-2015 19:51
@Vdasdasd: the problem is probably that you are overpowering the reeds. Try blowing verry verry softly.
05-01-2015 18:48
my 7 and 10 hole isnt working when i blow but it does work when i draw so please help me
18-08-2014 17:01
Rainer Söchting
Very interesting and very helpfull. Although I am not a jazz player this could improve my bluesrock a lot. Thank you Tinus.
05-12-2012 14:16
Hi Tinus.. I'm from Romania but I live in Italy now.I'm not a good the harmonica player but I try to learn via internet.Please I wish to explain me why allmost the harmonica musicians from the world,use the Suzuki Manji M 20 harmonica and not Special 20.Becouse here in Verona all the harmonica musicians use the Special 20.I buy three harmonicas an (A),(C) and (F),but I'm not verry proud of these harmonicas becouse the C harmonica it's broken when I'm done the bending, drowing the 4 hole.Now I see in internet this harmonicas Suzuki Manji M 20 and I wish to buy'm them. So..can you give me a vice,about this tip of harmonica ? please. Thank you so much. Aurel.
30-11-2012 01:12
Thanks for the info!
08-01-2011 06:38
Gapping is the main technique for the advancement of each harmonic. Thanks.
19-11-2010 14:04
@Kieron: hole one is a rather difficult overblow and a very technical overblow. It cannot be forced out as easily as other overblows so your technique needs to be spot on. The blowreed has to be gapped tightly but that doesn't have to interfere with normal play. The reed does have to be very straight in order for the blowreed to choke well. see this video for other tips: http://www.youtube.com/watch?v=80b3NM4ar9Q

2. for the hole five I suggest you isolate the reeds to see if it is the blowreed or the drawreed that is giving you trouble.
18-11-2010 17:53
Hi Tinus, Thank you first of all for your wonderful website. A real treasure trove of information. With your advice I have been able to set my harps up to overblow and overdraw. I haven't managed holes 1 or 2 properly yet and I am not sure whether my playing technique is lacking or my reed adjustments. Do you set the reeds fairly tight and does this restrict normal playing technique particularly on the blow reeds.

Part 2. Hole 5 is a problem, I can OB ok on this hole but it takes more force. The reed doen't sound like it is resonating easily and produces a rather dull unexpressive note. Any ideas or observations. Thanks, Kieron
13-09-2010 22:31
Hey Sagar, maybe you should read the rest of this site and view the overblowcom videos on youtube. I have tried to explain what I do to the harp to get it to play the way I like on the site and in the videos.
13-09-2010 22:03
Hi Tinus,

I am sagar from India.your videos are very good.my question is that the harp you are playing is customized to get all the notes you are playing?if so let me know how to adjust my harp reeds to get all the notes you are showing in your video.

12-05-2010 20:41
u kent tinus wat me in de harmonika plaagt, is dat ik de theorie en de schalen in mijn hoofd heb (ik ben een gitarist met vingerstijl ik bossanova speel). maar de chromatische harp doesn' t heeft het gevoel en slechts zal een diatonische custon antwoorden aan wat u om vertelt te doen. u bent gelukkig door uw harp aan te passen, is het hemel
12-05-2010 20:15
thanks tinus,
it is not my technic i am an advanced and play on stage.
but your text made me notice that i closed well the bottom of the reed near
the rivet and the gapped was open.
i arced the reed to open the bottom by reducing the curve
12-05-2010 12:37
@Romanos: if the drawreeds choke and bend when you do little or nothing then it could be because they are gapped too tightly. However it could also very well be that your technique is to blame. But opening them up a little should allow them to play normally and bend down further. If that doesn't improve how they play it is very likely that it is your playing technique that is at fault. Before you start messing with the reeds you should try playing with an open nose to see if the rreds respond well when you don't have a closed resonating system.
11-05-2010 21:21
Dank tinus het goed informatief was,
i messed with the 2 and 3 draw reeds(lee oskar A):
these isolated draw reeds are playing choked on
light air draw, and when drawing with more air they are bending down
whithout intenting to bend them, i tried the other holes(cheking my playing)and they are healthy
-is it the curveture or the offset?(the facing blow reeds are fine and gapped for 1/4 bending down when isolated)
also my 3 draw hole is bending down 3 half steps easily
but hardly 2 half steps to be controled.
ik houd van vele talen te spreken, maar het Nederlands is hard, moet u tinus bekennen
08-05-2010 15:16
@Romanos: All the blowreeds are gapped so they bend down approx. a quarter tone.
Also the drawreeds in 1,4 and 6, i.e. the holes that can only bend down a half step, are also gapped to bend down a quarter step. the drawreeds in hole 2 and 3 are gapped so that the drawreed bends down about 3 quarter tones, so that it bends at least past the half step bend.
By the way I am not German so if you want to write anything in my native language try Dutch :)
07-05-2010 18:50
hallo tinus, i want to know how to treat the draw reeds of hole 2, 3 where they should draw bend far and hole 4 which it should allow an overblow and draw bend a 1/2 step
you wrote above that the isolated blow reed should bend a 1/4 tone
-is that true for hole 1, 2, 3, 4, 6 or just the 2 and 3?
how far the isolated draw reed should bend? same for all?
Das eines Königaufstellungsortes
07-10-2009 13:54
When you setup the reed you aim for a amount of bendability on the blowreed. The farther you can bend the blowreed the more difficult it is to choke. So when setting up you isolate the reeds and set them up seperately. Basically you set up the reeds so that they bend about a quarter tone. After you have done that you play both reeds and fine tune the gapping to fit your needs.
07-10-2009 06:18
B illy Vienneau
I do not know hwat feel I am aiming for when setting up my harp. Almost as if I can set it up in a way where I can easily hit that one overblow. But yet I do not know if I made my harp so but I cannot not do it. Do you think you can send me an old reed plate with at least a good 1 blow and draw reed so I could play it and see what a good set up harp feels like with that one. It is hard to hit really hard.
30-08-2009 14:59
What a GREAT site!!! Thanx! Information about your student that sets up harps would be greatly appreciated. This is all new to me, Not the harp playing but the info you provide on the screen. Thanx again! BOB
07-10-2008 15:19
@Chris: thanks for the heads up. It was a type in the server address. The soundfiles should be working again now.
06-10-2008 21:25
Hi Tinus,
Great site! It seems that the soundfiles can't be found on the server.
30-08-2008 15:48
I fixed the audio.
29-08-2008 12:29
No the sound isn't working. Apparently on of the servers that I use to store my soundclips on has stopped. I'll try to move the soundfiles asap.
29-08-2008 04:11
is the sound working on the site or is it my computer
28-08-2008 23:49
28-08-2008 19:11
The setting up of the reed curve or arc is explained under the heading "arcing"
28-08-2008 18:08
how do you set up a reed curve?
29-07-2008 00:11
@ Daniel: the ten hole bend is not an overblow it is a regular bend. The difference between the hole 8,9 bends and the hole 10 bend is simply one of distance. The hole 10 bends down a whole step instead of a half step. Because of that the overlap between the two reeds is very likely to fall around the half step bend. At that point you are playing both the reeds and this is an unstable situation. On hole 8 and 9 this point is halfway between notes so it doesn't matter much. It is true that by opening up the gap on hole 10 you make it easier to play the half step bend. You widen the overlap and thereby make it easier to control.

The blownotes bend down in the upper register simply because the blownotes are higher than the drawnotes. So if you want to reverse it you have to retune the harp so that the draw notes are higher than the blow notes (just like the lower end of the harp. There are many layouts where this happens. Check out the chord and scale finder for some of these all draw bending harps
28-07-2008 22:32
About the 10 hole blow bend, the reason it mutes on the half step and is clear on the whole step is because it is actually an overblow. On the half step bend the blow reed is actually choked. So the way to get a half step bend on the 10 blow is the same way you bend an overblow up. You can also increase the gap on the 10 blow so it does bend a half step before choking. I don't know why that one chokes so much more easily than the 7,8 and 9. Does anyone understand why the top blow reeds bend rather than choke and why the bottom draws bend rather than choke? Is it reversible?
12-06-2008 19:33
@ Beki (the anagram master):

That is a very unusual problem. Most people have the problem that their overblows are too low. You are the first to have it too high. The only solution I can think of is to play the overblow with an isolated drawreed and then learn to play that relaxed an work on getting it up and down. I hope that helps.
12-06-2008 19:07
beki Lenn
My hole 6 overblow is getting much easier to play & stronger, but I have been consistently getting a B instead of a B-flat. I have heard that overblows can be bent down & up but I cannot get any lower (sometimes I can get a flat C). The gap for blow and draw reeds is extremely low. Is this a common problem & what should I do about it?
11-06-2008 19:44
The 10 hole bends can be played clear and distinct. Yes gapping is part of this. The blowreed has to be able to bend past the half step bend before it chokes. The isolated drawreed should be able to play higher than the half step bend before falling silent. (all on the blowbends) You can adjust this with the gap. You want a nice overlap between the blowreeds part of the bend and the drawreeds part.

Also practice bending the isolated reeds so you can get a feel for the overlap.
11-06-2008 04:33
Ben Klein
This is not really related to overblow playing, but it's related to getting the 3 octave chromatic scale.

I have not been able to get hole 10 on my C harp to blow bend a half step (to B). David Barrett says in Building Harmonica Technique, "Don't worry if you're unable to get the half step bend, the 10 hole pretty much just snaps into the whole step bend and there isn't much you can do to control it." But I know there is, because I've heard it played. :)

Could this possibly be solved by gapping?

By the way, great website :-) thanks
04-05-2008 11:40
Whatever you do, don't throw it away. I can't say that I used to damage many reeds when gapping, but I did break a lot of reeds while learning to overblow. I learned how to replace individual reeds early on. So if you mess up a reedplate please keep it safe because the other reeds can be used to replace reeds you break.

I was always very carefull when it came to gapping and arcing so I didn't damage the reeds too much. Gapping is something of an iterative process, changing the offset of the reed in tiny increments and testing it each time to see if it is right. Going to far and then going too far back is also part of the process. There is an optimum somwhere, but you can only tell if you have reached it by going past it.
04-05-2008 07:33
When you were 1st adjusting your harps, did you ruin alot of them? My A harp for example, I was trying to adjust so I could overblow but i messed up the reed so bad that i had to settle on adjusting it so I can only get the 4 blow and not the ob. I dealt with it at first but I'm probably just going to throw it away and try again.
10-12-2007 11:03
No I don't make harps, can't find the time for it. I do have a student that is brilliant at setting up harps so email if you want info on his work.
10-12-2007 02:30
Davey G
Hello Tinus, thank you very much for helping with the information , I will continue to try and get overblows , I got a clear overblow last night after 15 minutes of trying on blow note 6 on my golden melody harp , I will try your re gapping method too. Thanks again , hey do you customize harps for sale ?.
10-12-2007 01:19
All examples are played on a C harp. The gap examples are played on hole 5
09-12-2007 20:37
Davey G
Hi well thats good , I was talking about the non valved suzuki model !, in your mp3 examples of good and bad gapping what key harp is it and what holeis it that you are blowing on please ?
09-12-2007 20:21
I thought Davey was talking about the Suzuki Overdrive...
09-12-2007 17:42
With bendable suzuki you probably mean the valved harps. These don't overblow since the blow reeds are isolated. I don't like them because you can't overblow them other people do like them. Bending valved blowreeds is a whole new technique that you have to master and the intonation is just as difficult as the intonation on overblows.
09-12-2007 17:40
I have heard very good things about the Suzuki firebreath and I think the Seydell harmonicas, favorite black and 1847 are very well built harps that overblow really well. Whatever harmonica you get, if it isn't a custom harmonica, you will have to set it up yourself. The harmonica has to be set up for your playing so you are best of if you can do this yourself.
09-12-2007 09:50
Davey G
Hello , I think this is very cool information , I am still trying to get a good clean overblow , I have boughttwo Golden melody harps as I was told they will over blow better than most other brands of harp. What is your advice or opinion on the Suzuki model that is available so you can bend all the notes blow and draw !
What harps do you recommend ?. Thank you for any information.
Thanking you David Godman from New Zealand .
24-01-2007 14:05
The overblow is played on the drawreed (the blowreed is chocked), if the drawreed responds well it will become easier to play the overblow, so yes a well gapped drawreed makes the overblow easier to play. Also the closer the drawreed is to the plate the easier it will be to bend the overblow up.
22-01-2007 17:38

I remember reading somewhere that the draw reed should also be gapped closely to the reed plate in order to make the overblow easy. Is this true? I recently have started to incorporate OB's in my playing and any advice you have would be appreciated.

22-02-2006 10:41
If you applied wax and the reeds still squeek you need to reapply the wax. The purpose of the wax is to stop the reeds from squeeling. If applying the wax didn't stop the squeeling then the wax has little use.
I am interested in the kind of wax you used. Does it have a brand name?

If you can't get the blowreed to sound after you have choked the drawreed you might want to try with an open harmonica. Block the drawreed completely and try to overdraw the note on the blowreed alone. If you can do that you should also be able to find the overdrawn note with two free reeds.
21-02-2006 01:12
Thanks Tinus. I applied wax (actually used orthodontic wax instead of beeswax as it was easier to mold), but that didn't alleviate the squealing. I don't have to use much force at all to choke the reeds on any of the holes, especially up high. The high notes actually choke suprisingly easy and much easier than when I try to choke holes 1 and 2. But regardless of how slow and gently I move into the choke, I have yet to hear a note. Just the squealing on 7 - 10.

I'll keep trying...
21-02-2006 01:05
The high pitched squeeling sound is a torsional vibration of the draw reed that sometimes occurs when the reed is choked. It can be remedied by using nail polish or beeswax to stabilise the reed. See the "waxing the rivetend" bit for more info


If you can choke the reed you should be able to find the spot where the overdraw sounds, give it some time and be carefull not to rely on force to get the blowreed to sound. Just take some time to find that spot where the overdraw just drops in on you and remember that you need more and more presicion the higher up the harp you get.
17-02-2006 21:55
Thanks for the tips Tinus. I've got holes 1 - 6 set up now and they are (relatively) easy to choke and get an overblow. On the low end I get what sounds to be a vibration of both reeds, which I'm attributing to being new to OB's since if I'm patient I'm able to modify my embuchure to get just the OB.

Now I'm working on 7 - 10, primarily 7. Choking the draw reed is actually pretty easy for me and I haven't had to modify the reeds much here, but the OD note isn't sounding, just a high pitched squeal. I'm assuming this is an arc/gap problem on the blow reed since I'm able to choke the draw.

Still working at it... Luckily so far I don't have to chuck this harp due to a mistake, but I'm keeping my fingers crossed...

17-02-2006 01:33
What you describe sounds like a reed that is gapped too closely. It is true that the easiest way to overblow is to just close the blowreed completely, but as you have found out that makes playing a normal blow note very difficult.

I usually gap the blowreeds while keeping the drawreed close with a finger. I try to get the reed so close that I can bend down the blownote approximately a quarter tone before it chokes. That way I can overblow the note comfortably without the blow reed getting stuck.

I think that you just need some practice, both with gapping and overblowing, to find out the right gap for you. There is an optimum somewhere and sometimes it is difficult to find.
16-02-2006 21:24

Thanks for the input on waxing. I'm trying to modify my first harp and I've spent what seems like forever on a single reed. If you can help at all, I'd appreciate and feel free to email me directly.

On the 2 blow, I've been attempting to emboss, arc and gap, in that order. The problem is, and it's the same for the 1, 2 and 3 blow, it seems to take a lot of air to get the reed to vibrate, even for a standard blow note. After messing with the 2 blow for the last few hours (yes, hours), it just doesn't seem to change. In fact I notice now that the harder I blow into the hole, the longer it takes for the reed to vibrate. I could be crazy or just a newbie (which I am), but I just don't expect to hear as much wind coming through the blow notes as I am. Also, I notice after adjusting the reed and getting an overblow on it, the reed will then get stuck and I can't blow it out, I have to readjust it which obviously changes the OB ability yet again.

Any chance some of this is familiar to you and perhaps you have some advice? Thanks for your time and help, and again for the website.