Speakers that don't cause interference

[Ozman]

I have my Altec Lansing inMotion speakers directly connected to my Sangean HD radio tuner. I noticed that my speaker are causing interference nearby the tuner.
do you guys know if an equivalent type of speakers that would not cause interference.
thanks

 

[Chuck]

Are they powered speakers? If so, it is probably the other way around. The tuner may be interfering with your speakers. Go figure, but HD tuners spew out all kinds of extraneous RF. They even interfere with themselves. The AM loop antenna comes with a long lead in wire so you can get it away from the tuner. It's for good reason. Try moving the speakers away from the tuner and see if that helps.

 

[Ozman]

never thought of it that way. I have moved it away from the tuner and it does help. I am in such a rural area of VT that every little bit makes a differerence. what in the specs would cause the interference?

Are they powered speakers? If so, it is probably the other way around. The tuner may be interfering with your speakers. Go figure, but HD tuners spew out all kinds of extraneous RF. They even interfere with themselves. The AM loop antenna comes with a long lead in wire so you can get it away from the tuner. It's for good reason. Try moving the speakers away from the tuner and see if that helps.

 

[mikl73]

I would expect those speakers are also not sheilded in any way also.

 

[Chuck]

never thought of it that way. I have moved it away from the tuner and it does help. I am in such a rural area of VT that every little bit makes a differerence. what in the specs would cause the interference?

An HD tuner is really just a dedicated purpose computer. Try putting an AM radio next to your computer and you will probably notice a lot of noise that is emitted from the PC. Your HD radio does the same thing. In fact, there are tons of noise generating devices in most homes, including computers, some cell phones, wireless modems, fluorescent lights, TVs and lots of devices that have microprocessors in them.

The "self interference" found on most HD radios is one of the big problems to overcome to get them to work properly. The manufacturers could probably do a better job of shielding these radios if they really want to make them work.

 

[Chuck]

I would expect those speakers are also not sheilded in any way also.

Probably so, but the shielding used in most speakers is for magnetic purposes so they can be used around CRT type monitors.

All a speaker has to deal with is frequencies between 20 and 20KHz, more or less. If it is a passive speaker, then nothing in that frequency range will cause interference to an RF device like a tuner. If they are powered speakers, there is a possibility that they use a switching power supply, as opposed to a wall-wart or built in power supply using a conventional transformer, some diodes and a couple of capacitors. A poorly designed (or malfunctioning) switching supply can cause RF interference.

Most computer type powered speakers don't use switching supplies. Usually, there is a wall-wart type conventional power supply. Most of the speakers I've ever seen that had switching supplies were fairly high quality (modestly to very expensive) devices and didn’t cause any big RF problems.

If you want to find out where the interference is coming from, an old AM transistor radio makes a good tool to do some troubleshooting. Tune it to an open frequency near the low end of the dial and move the radio into close proximity of the suspected device. You’ll hear the noise increase in volume through the radio’s speaker as you get closer to the source. Once you identify the source, you can then work on a possible cure.

 

[136kgb]

You know IBOC is a completely flawed system, especially on AM and this just proves it. I will stick to my analog McIntosh tuner, preamp, and amp, and my REAL ALTECS, the 604E's. They all produce fidelity far superior to anything that "HD" can claim! You know with HD TV there is a very real difference, with HD radio yah there are more choices, but the choices are crappier than the main channels (which are really crappy). Buy a good Technics SP-15, SME 3009 Series 3 arm, and a Shure V-15, and a complete McIntosh rig then you have pure HD!