1. The Songs. Songs of goyim and chillonim are not to be played, even with holy words. Similarly, songs of a rebellious nature are not to be played, even if they were written by chareidi people, such as all the songs that are made in the style of cheap street music.
A few sources might be useful here: See Rambam in his Perush Hamishnayos to Avos 1:16 where he describes as foolishness those people who protest if they hear songs sung in a foreign language even if the subject matter is quite proper. We see from here that the Rambam knew of secular songs that were mutar, or even recommended. The Chida (Birkei Yosef Orach Chaim 560) quotes the Sefer Chassidim that says one shouldn't sing "pritzus" songs, but there is nothing wrong with using the melodies. Also see Teshuvos Yechave Da'as 2:5 where he rules that it's mutar (and perhaps even a mitzvah min hamuvchar) to sing kedusha to arabic love songs.
2. The Style. Even the traditional songs must be played in a Jewish style and in a respectable manner fitting to the holy words, and it is not at all permissible to play in the style of the porkei ol.See my comments above for a small selection of sources that would disagree.
3. The Instruments. The quality of the music is influenced by the instruments that are used. Unfortunately, most bands use instruments that are especially made to play wild music, and have no place in respectable music. It is recommended to play only with respectable instruments, or at least to take care to play respectfully, that is, not to distort the sound of the electric guitar, and to refrain from playing wild abnormal rhythms on the drums.Agin with the intolerant language. A rhythm may not be to the listener's satisfaction, but that doesn't make it "abnormal."
4. The Drums. It is necessary to take care that: 1] The sound level of the drums should be less than the main melody; 2] Not to play wild rhythms.This is a meaningless statement. What constitutes a "wild rhythm? I agree with the point about the volume level of the drums though.
5. The Volume. It is forbidden to play at a volume above 90 decibels, and any band that plays louder should be rebuked. It is advisable to demand that the musicians not use ear plugs.I agree that the volume should be kept low and have said so in the past (here and here), but the assertion that the band should play without earplugs is foolish. Anyone who is regularly exposed to even 90 decibels as part of their job should wear hearing protection. There is a difference between attending an affair once in a while where the volume is at 90decibels, and spending five hours at a time, night after night, exposed to such levels.
6. It should be stressed that only the person who pays the band has the right and the responsibility to decide what or how to play, and nobody else has the right to request anything else without the permission of baalei hasimchah.I actually agree with this one to an extent…especially, when the guy with the "good voice" who invariably is present comes over to ask if he can sing with the band.
The following details were added by the members of the committee to explain the above guidelines:
1. The Songs. Recently songs have been taken from the non-religious media and "converted" by changing the words to pesukim etc. These songs creep in by means of the "religious" radio and by demand of irresponsible youth. They find their way to the weddings of bnei Torah, together with other wild rebellious songs written by "religious" singers. Regarding the songs of the chareidi pop stars that are generally songs of chutzpah and rebellion, the Gaon Rabbi Shmuel Halevi Wosner wrote: "We are obligated to distance ourselves from this, as they mix the posul with the kosher and the kosher is also profaned."As I mentioned earlier, the songs using actual secular melodies are rarely played at affairs here.
2. The Style. In order to understand how a band can change a pure Jewish song into a pop song, one should pay attention to the way they play the song before the chuppa and note the difference in the way it is played by the band and the way the guests sing it outside. By adding a few small changes to "jazz up" the melody, it is transformed into a different song and is now unsuitable to accompany the chosson and kallah to the chuppah. This is how most kosher songs are played today in order to adapt them to the modern style and by doing so they lose all of their spiritual content. Therefore it is extremely important to choose a kosher band whose musicians can play according to these rules.The tradition of playing embellishments of the melodies goes all the way back to the beginnings of Chassidic music. The earliest recordings contain ornamentations and embellishments of the melodies.
I do think that the musicians selected should have a strong background in – and experience with – Jewish music.
3. The Instruments. The electric guitar is made only for use in rock and pop music and it has no place in any form of kosher music. It is possible to play it in a respectable way and there are a few avreichim who do so, but the musicians who play this instrument in the way it is really made to be played spoil the whole kedushah of the wedding.Almost every musical innovation has been criticized by some as inappropriate when it is first introduced. The waltz rhythm was banned in the Prussian courts as inherently indecent. Are we going to ban all those Chassidic waltzes?
The same problem exists with the saxophone, referred to 80 years ago as "the devil's flute." Everything depends on the musician. It is possible to play it in a respectable manner or in a coarse vulgar manner. Therefore it is preferable to request that the clarinet should be used instead of the saxophone. (The baalei simchah should know that it is their privilege to decide which instruments they want to be used.)
Other points that should be mentioned: not to amplify the low bass tones more than normal, and not to use weird electronic sounds or distortion.I think that it should depend on how the distortion is used. Not all distortion is bad, although some of the players on the local wedding band scene here in NY do overuse it.
4. The Drums. Also, the modern set of drums was created for playing non-kosher music. Therefore it is important to avoid drummers who do not understand how to play in a suitable style. It should be known that the definition of rock music is when the rhythm is the dominant factor over the melody. Therefore the drums and all percussion instruments should not be as loud as the other instruments. And especially at weddings in Yerushalayim, they must be careful not to make the rhythm of the drums louder than the singer. [It should be noted that the function of the drums is only to accompany dancing, as is mentioned by the Malbim, Yeshayohu, 24:8].Interesting definition of rock music there. I disagree, though.
5. The Volume. Medical experts say that prolonged exposure to noise levels over 90 decibels damages hearing and general health. The noise problem can be solved, bezras Hashem if every wedding hall will be required by law to install a noise meter that will disconnect the electricity when the noise exceeds this limit. The noise level should be measured from the place where the people dancing come closest to the speakers. Where it is not possible to measure the sound level, the band should be told that they are to fix the volume according to the judgment of the baal hasimchah, and they should be warned that if they do not listen when told to reduce the volume, they will not be paid.An interesting approach that could help solve the problem. The method suggested feels quite repressive though.
6. The Singer. The status of the singer at weddings today is very problematic since most of them try to imitate the frum rock idols both in the way they sing and in the way they move and dance while singing and in the way they pronounce the words. If they do this it is better to ask them not to sing. All of these guidelines certainly apply when playing inside a beis hamedrash at a Hachnosas Sefer Torah or Simchas Beis Hashoeva.Frankly, I've worked with many of these singers, and in general, I don't find that they move around at weddings the same way they do on stage at concerts.