Andrew's blog

Tweaking harmonicas: Measure what you change

This is about methodology.

I made yet another harmonica tweaking video.

Here's a video demonstrating some of the things that are straightforward to quantify so that you can make changes that have a measurable benefit.

Some of these things include:

Tuning: It's easy to measure the pitch of a reed and whether it's in tune with another reed. Play all the octaves available and listen for "beating".

Bending: Bend the 3 draw (or any other bend) with as little force as you possibly can. You will find a "blind spot" somewhere in the middle where the workload is handed off from the draw reed to the blow reed as you bend down. How much work is needed to "skip over" this blind spot can be felt, albeit subjectively; it tends to be more work on lower key harps. We learn to "skip over" this blind spot early on when we are learning to bend. A well-playing harp can be played with very little breath force without having to work hard around the "blind spot".

Reed shape efficiency: By playing a single reed using your lips on the plate off the comb, you can get sensory feedback on how easily the note responds, how much flow you need to make the note sound strong, and how loud the note is. A well-shaped reed will make the whole reed plate vibrate when you play it.

Reed shape efficiency (again): By bending the single reed's note down, you can determine if the reed is prone to squealing. That's a great indicator of how efficiently the reed is set up.

Sending harmonica reed plates by mail (the safe way!)

I usually prefer to work on a harmonica along with its comb and cover plates. However, there are times when I only require the reed plates. This can save on shipping costs because reed plates can be sent through regular mail.

You do need to be careful to package them in a way to try to avoid damage or loss. If you just drop reed plates into a plain envelope, I probably will receive an empty envelope with a hole in it.

Here's a safe way to package reed plates for transit by regular mail. Please be advised that although this is a great way to package them, regular mail is a lot less safe than sending them as a parcel with insurance. I cannot assume responsibility for list or damaged goods. It's up to you to make the choice whether the cost savings is worth the risk.

Step 1 - Place the reed plates back-to-back. Make sure the reeds are on the out side of both plates.

Step 2 - Wrap them up in wax paper.

Neatly fold the paper around the reed plates.

Step 3 - Use wide packing tape and stick the reed plates to a piece of cardboard. Make sure the reed plates are under a "bubble" of tape and completely covered.

Step 4 - Repeat the process for any other reed plate sets you are sending. Position the plates so they are parallel and centered on the cardboard.

Step 5 - Cover the first piece of cardboard with about piece of the same size. Make a sandwich.

Step 6 - Tape it up. Wrap the tape around the cardboard in both directions.

Step 7 - Put the cardboard sandwich into a bubble envelope and you are ready to send it!

Research and development of optimized combs

I have an ongoing process of quality improvement and I devote some time and resources for research and development on certain projects. I've enlisted the help of a number of players to do some testing. I need the input of different players to determine if a particular change to a comb design is indeed an improvement that can be measured.

In cases where the improvement is felt across the board, the change becomes part of my standard design.

In some cases, the change is subjective. Some may love it while others may hate it. In that case, I can offer the new feature as an option so that customers can get a truly customized comb, made to order with or without any desired design tweaks.

I recently had some testers compare two combs. Both were identical except for the hole spacing. The Hohner Rocket boasts wider spaced holes and I wanted to provide that experience without making the comb tines too thin.


Wide openings and standard openings

The tines are only thin at the opening and become a normal spaced channel to provide less compressible volume a little further down. This is to improve responsiveness. The hole openings are 40 per cent wider than standard Marine Band comb openings.

Feedback is trickling in and I am considering it carefully.

My next test will involve resonance chambers. I feel the consensus is that thinner combs offer better response because there is a smaller compressible volume between your lips and the reeds. But thicker combs offer a larger resonance chamber and some prefer the tone of a thicker comb. Here is not-too-thick comb with enlarged resonance chamber. The aim of this design is to get the sound of a thick comb with the responsiveness of a thin comb.


Comb with built-in resonance chambers


Comb with standard shaped tines

I will be looking for more testers in the near future. I need to finish getting feedback from the first test as well as tweak the "resonance chamber" design before I call for more testers. Stay tuned!

***Update 2016/05***

I have come to the conclusion that resonance chambers have no real benefit and some drawbacks, namely that they can interefere with the performance of some bends/overbends. The original, classic comb design with straight chambers provides the best, smoothest performance.

Although this doesn't result in any innovation, it does provide some helpful evidence as to what makes a harp play well. I believe this project was time well spent.

Acrylic (Plexiglass) harmonica parts

Acrylic is horrible on the environment to make in terms of the chemicals that are put into the air but it is sustainable once it is produced. It can be recycled or re-purposed. That being said, my community does not recycle acrylic. It goes into landfill.

So when I stumbled upon a small amount of discarded Plexiglass, I decided to give it a new home. After some tinkering, I found a way to produce some pretty nifty combs and French Tuners!

Once the sides are flat-sanded for air tightness and the tips finished to a smooth matte surface, they look like they are made of ice. Canadian-made ice combs for sale!

I am offering these combs at budget prices. They look terrific, offer quick response and sound great, but they don't offer the same juicy timbre as my Dark combs. They are most certainly a huge upgrade from stock combs and will add some punch to your harps.

If you want a comb that gets the job done at an economical price, this is the comb for you.

Limited quantities available. Click here to order. (Sold out!)

Playing a harp while giving out advice

My wife says I look like a clapping seal.

Yes, I do.

Video: Replace Marine Band nails with screws and install new comb

This is a quick and easy way to install a flat comb in to a Marine Band harmonica. The stock comb has dimples to make room for the ends of the rivets which hold the reeds. My combs provide more surface area to make an airtight seal with the reed plates and the rivet ends need to be flattened.

This is a harp in the key of G. The end result is a fantastic harmonica that is loud and responsive. I was happy with the instrument but was not satisfied with the 4 overblow due to the shape of the reeds (out-of-the-box profiles).

I spent a few minutes and did some re-shaping of the blow and draw reeds to make them more efficient. It's much more work than just gapping. But the end-result is a 4 blow that is not tight and plays normally with hard pressure as well as a solid - and bendable - 4 overblow.

Is my vintage Marine Band a lemon? How to spot a bad Marine Band harmonica

Restoring old harmonicas can be rewarding. Some of those old harps have a lot of soul!

Some Vintage Marine Band harmonicas are worth restoring because they have the potential to become responsive instruments with that earthy Marine Band sound.

But some are not.

Hohner went through a difficult time in the late 80s and early 90s and the quality of their harmonicas suffered. No matter how much work you do on such a harp, the result will be a serviceable harp at best. When they were first bought, a lot of them were hardly played because of the poor quality and they were simply put away. Today, these harps are surfacing on online markets as Vintage harmonicas in great "cosmetic" condition! They are cosmetically excellent because they have had barely any use due to their poor quality out-of-the-box.

How can you tell the difference between the good and the bad vintage Marine Bands? Here's a simple way. This method can help you spot a lemon over 90 per cent of the time.

Take a look at the back of the harp. Flip it upside down and look closely under the cover plate. How many nail heads can you see in between the reeds on the draw side (the bottom reed plate)? If you can see three, the harp is from a good period - either before or after the difficult time in the 1980s and 1990s.

If you can only see two nail heads, you have a harp that is most likely not going to be as playable as you would like it to be no matter how much work you do on it.

Sandwich-type harmonica made from recessed reedplates

Harmonicas like the Lee Oskar, the Hohner Special 20 and the Suzuki HarpMaster have a "recessed" plastic comb that surrounds the reed plates. Your lips don't make contact with the front of the reed plate, instead, they are in contact with the plastic comb.

I think the best practice for upgrading these models of harmonica is to *keep* the factory ABS comb. Extra performance can be gained by making the reed plates perfectly flat by flatsanding the draw reed plate and using the Reed Plate Claws™ to straighten the plates.

But for those hobbyists who like to experiment with the tonal qualities of switching from an ABS "recessed" comb to a solid surface "sandwich-type" comb, the change can be made.

To replace the stock comb with a "sandwich-type" comb, you need to round off and smoothen the front of the reed plate so that it's comfortable in your mouth.

Here's how you do it

Start with some fine sandpaper. Sand down the draw reed plate as described in the document "Preparing a reed plate for use with a flat comb." This gets rid of the protruding riven ends and allows the reed plate to sit properly on the comb. It makes the harmonica more airtight and is recommended on all harmonicas, even Suzuki harmonicas which have no rivet ends.

Next, hold the reed plate at an angle and sand the front edge of the reed plate in a circular motion.

Next, do the same to both sides.

Using a piece of 600 grit (or higher) sandpaper and polish the front edge. Be sure to avoid contact with any reeds.

Place the side of the reedplate on your working surface and run the 600 grit sandpaper back and forth over the edge. You are making a nicely rounded edge along the side of the reed plate. Don't be afraid to rub pretty hard. Just be sure to not catch any reeds when you work on the draw reed plate.

Once you are done, the corners should look smooth and comfortable.

This is a very comfortable and airtight harmonica made from Suzuki reed plates with a sandwich-type comb and a set of Special 20 cover plates. You can't buy a harp like this in stores!

Special note regarding Lee Oskar harmonica comb swapping:

The cover plate on a Lee Oskar just barely sits on the edge of the reed plate. When converting a Lee Oskar harmonica to a sandwich-type comb, moving the cover plates back will help improve airtightness. A very easy way to accomplish this is to enlarge the cover plate holes. Simply drill the existing holes with a 1/8 drill bit.

Once assembled, you will be able to position the Lee Oskar cover plates further back.

Holes 9 and 10 on a Lee Oskar

My very first "real", professional-grade harmonica was a Lee Oskar. I always had the hardest time bending notes on that thing. Had I known then what I know now, it probably would have become my favorite harmonica. Instead, I spent years fighting with Lee Oskar harmonicas.

One of the biggest problems with these kinds of harps is that they are not airtight. They seem to me to be pretty difficult to play up in the high end. I think I found out why. Whenever I sand the draw plate of a Lee Oskar harmonica, I notice that holes nine and ten share a low spot. They share common airspace. This is right where the serial number is stamped on the other side of the plate.

After sanding the plate down half-way, this is how it looks. The low spot is the dark area on the plate:

After some more elbow grease, this is the result. Everything is shiny and all the same color.

Once reassembled, the harmonica is much more airtight and the bends are much easier to control - especially the blow bends.

Making a Lee Oskar harmonica play overblows

With good reed work and a little embossing, any harp can play overblows as passing notes.

The overblows in this video can be hit cleanly. They cannot be played with any more expression such as being sustained or bent. That's the difference between a regular harp that can play overblows and an "Overblow" harp. The overbends on the Overblow harp are meant to be played with expression and will not squeal or drop out when bent up.

Pages

Subscribe to RSS - Andrew's blog