Hooking up a discman to powered speakers. Any possible problems?

Factual Questions
1

I just bought a Sony Discman, and I want to hook it up to to some large-ish speakers (which I am still to buy) for my bedroom. I will most likely buy a 2 speaker set with a sub-woofer.

Now, the Discman has no line-out jack, so I’ll be plugging it through the headphones jack. Audio will therefore flow from the discman via the headphones jack through to the sub-woofer and then on to the individual speakers. Going by my extremely limited knowledge of things electrical, this arrangement should be just fine, at any volume level.

But I do recall a friend telling me (several years ago), that if I did that I ran the risk of frying the discman. The reason, IIRC, was that at high volumes, the speakers would cause the amplifier in my discman to burn. However, at that time, I had a walkman and I was contemplating connecting it directly to the speakers, i.e. no sub-woofer (which would have its own built-in amplifier, right?) in between.

So what I want to know is:

  1. What was my friend talking about? and
  2. Can I hook up my discman to the speakers as described above?
2

I hooked my cd player up to my altec lansing ada880 speakers once. Nothing fried, and I turned it all the way up.

3

Beats me. Sony headphones have an impedance of 8 ohms, the same as most speakers you’d connect. From the amplifier’s perspective, there’s no difference between the two.

Yes. Just keep the discman volume down so you don’t overload the powered speakers’ input stage. (Probably wouldn’t cause any damage, just sound bad).

4

So as long as I keep the input volume low, I can turn up the output volume (i.e. speakers) as much as I want without any loss in sound quality, right?

5

Yes.

Set the volume on the discman about half way between min and max, and away you go.

6

Great! Thanks a lot!

7

Subwoofers generally don’t have outputs to other speakers. I doubt you’ll be able to follow your wiring plan. All the home theaters I’ve seen have a dedicated output from the amp to the subwoofer.

You may have to skip a subwoofer. I can’t say for sure, as I haven’t shopped for speakers in a while. It’s possible you can find a set wired as you expect.

8

Good point, Boyo Jim. I assumed gouda was talking about something like the Cambridge Soundworks range, which consist of an amp built into a (sub)woofer enclosure, with outputs for a set of satellite speakers. This kind of set up is pretty common. Sorta like the Bose stuff, but way, way cheaper and just as effective.

9

I don’t know the brand, so it’s not very helpful, but the subwoofer my Dad bought last year had outputs for other speakers.

Also, he’s going to have to go from the headphone jack to RCA via an adapter, right? Anyone think this will be a source of noise?

10

Yep, this is exactly what I’m planning on buying - it’s a relatively inexpensive set up that sounds decent enough in a smallish room.

I’m not sure I understand what adapter you’re referring to. I intend to use a regular cable with one plug on the discman end and 2 plugs on the subwoofer end. I’ve done something similar with my old tv, although there was no amp/subwoofer in between then. It worked just fine.

Incidentally, what’s the difference between a line-out jack and a headphone jack?

11

A headphone jack is intended to drive headphones. The volume (voltage) is controllable, and the output impedance is low, e.g. 8 ohms.

A line out jack has a fixed voltage, and may have a higher output impedance. It’s intended to drive another amplifier.

The actual voltage of the line out jack is not well defined. It’s supposed to be 0.775 V rms (1 mW into 600 ohms).

But lots of common gear has a line out level of 0.245 V rms, which is equivalent to 0.1 mW into 600 ohms.