What does clipping sound like?


I have been wondering if the break up distortion I hear with my 60 watt tube amps is because I have insufficient power for my 91db 6 ohm minimal speakers. I do question if that rating of my speakers is correct.
When the music swells, I get break up sound. It is not on low notes or high volume. I do wonder how my speakers would perform with a lot more power. I have always thought that any speaker likes more power.
mglik
What speakers do you have? I have found that all of my speakers sound better with more powerful amplifiers, but I'm a SS amplifier guy. For me, tubes are for preamps. I know that some speakers are hard to drive with some tube amps. Tube amps generally don't like lower impedance speakers. By that I mean below 8 ohms nominal. As for sound of distortion, pretty much what you describe. Just starts to sound crappy, unclear and watch out for blowing tweeters. After I went to more that 500 W/channel, no more blown tweeters.
When the music swells, I get break up sound. It is not on low notes or high volume.
Could you explain this in more detail? So there's no distortion at high volumes or bass notes?
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I have Tetra 606s. For a long time I pushed them with a 300B SET at 8 watts. Clearly, they wanted more power. Seems like I am pretty confirmed that the scratchy breaking up I hear on swells is clipping.