What do you suppose these knobs on the back are for?

[MichaeI]

The speakers are RBH Model 816. They have one knob on the back of each speaker. It sounds like the bottom driver goes out when I turn it all the way one way, but it may be more than that. It also sounds like turning the treble down--I don't know. This is why I ask: I love their sound, so I use them for everything (video games, TV, music, etc.). I never have any problem with them, whatsoever, but recently I decided to watch Total Recall on VHS. The cassette is hi-fi as well as the VCR (also tried on non hi-fi VCR with same result). In the very beginning of the movie, when the ground gives way, and Arnold falls and his face-shield breaks, the sound gets super, super muddy and distorted--like playing 20 hertz through cheap computer speakers and turning it all the way up. I turned on my Polk Audio PSW 505 (23 Hz - 160Hz) and it was really deep bass, but the RBHs go down to 28 Hz themselves, so, weird. I wonder why I have never had this audio problem before, and if the knobs on the back could mitigate it. This time it was really noticeable, but maybe it isn't all of the time. I will have these speakers for the rest of my life, so I don't want to damage them. Thanks : )

 

[Blue Shadow]

Tweeter level is the most common

 

[F1nut]

Some info for you. First, that Polk sub has a -3dB of 35Hz meaning it falls off a lot after that, so while it may make some noise at 23Hz it is so little it's not worth mentioning. The same applies to those speakers. They are giving you an overall frequency rating, not the -3dB, which is likely to be in the 40Hz range, if that low.

A friendly tip, get some better speaker cable. What you are using looks like it's thinner than lamp cord.

 

[crazy-in-az]

That's for adjusting the tweeter level as Blue Shadow has pointed out. It sounds like they need to be cleaned with some contact cleaner.

 

[MichaeI]

Some info for you. First, that Polk sub has a -3dB of 35Hz meaning it falls off a lot after that, so while it may make some noise at 23Hz it is so little it's not worth mentioning. The same applies to those speakers. They are giving you an overall frequency rating, not the -3dB, which is likely to be in the 40Hz range, if that low.

A friendly tip, get some better speaker cable. What you are using looks like it's thinner than lamp cord.

I think I get what you are saying. Since the Polk sub drops off so quickly, I wouldn't hear any distortion, but I may on the RBH floor speakers if they are trying to play that low frequency? That makes sense. Yeah, need to change the cables. I cut them off of some junk Boston surround PC system I found at the thrift store. Thanks : )

Tweeter level is the most common

That's for adjusting the tweeter level as Blue Shadow has pointed out. It sounds like they need to be cleaned with some contact cleaner.

Sounds likely. I don't know much about that, so I will have to read up on it. Thanks : )

 

[gdmoore28]

Michael,
Do you have a link with specifications/owner's manual for the 816s? What size woofers are in them? I assume you are running them full range? What type of receiver?
GeeDeeEmm

 

[amb3cog]

I'm very curious about these. Can't find much on the web. I found one thread on here where the OP said he got them at a thrift, or something. They seem like they might be a hidden gem.