I think that I have put in too big of plugs into my open-hole flute. I popped them down into the flute and out rather than sticking in a thumbtack and scooping it up and out. I have done this more than once to play. Would this affect the keys/pads? (My flute is a Di Zhao 500 - similar to the Powell Sonare 501.)

Hi there, Since I don't know precisely what kind of plugs you have (they vary from shop to shop and flute to flute), I'll give you the most common options.

Probably the simplest plug is a simple disk of cork, plastic, or silicone that is placed in the key. These may or may not have a "top" on them. If they don't have a top, they simply sit in the hole without protruding out the top, and they can simply be punched into the flute and then caught as they fall out the bottom of the instrument. If they have a top (such as a metal disk that covers the hole and protrudes beyond that opening), then you'll need to carefully peel them out. Usually, a fingernail under the top is enough to do this.

There are also more substantial plugs such as the Powell "Plug-O's" which is what I suspect you have here. They can be quite difficult to place and remove, but do a great job of plugging up that hole and look good too. This type is made of solid metal (Silver for the actual Powell product, but other materials have probably been used) with an O-ring to create a seal. These require a special tool to remove them, and if your Pearl has Plug-O's, you should have been provided with such. To remove them, this tool will need to be placed between the tonehole and key cup (underneath the key), and the plug pushed up out of the hole. Be careful not to exert pressure on the key cup while doing this, as you can bend them, creating leaks that will affect performance, and take care while using the tool that you do not puncture, rip, or otherwise damage the pads.

Of course, if you can't manage to get the plugs out, there's nothing wrong with just leaving them in. The holes in the keys don't do anything for tone, response, or intonation, so plugging them is not a problem in that respect. You should only need them open if you are required to do extended techniques (multiphonics, microtones, etc.), pitch shading, or some notes in the fourth octave. For the VAST majority of players, they serve absolutely no use, so if worse comes to worst, just leave the plugs in there.

I hope this is helpful. If you have any other questions, please don't hesitate to ask.