good stereo switch recommendation needed

[denti alligator]

I have three stereo inputs I switch between frequently to go into my SEX amp. I would like to get a simply but effective switch that does not in any way interfere with the signal. Recommendations? I can only find things like this or this, but these look awfully 'cheap.' Don;t get me wrong, I don't want to spend a lot of money, but I fear for the quality of my signals with such devices. Should I set aside my worries or is there something else I might consider?

 

[Doc B]

DIY it man! Buy a four pole three position switch, four pairs of RCA jacks, some wire and box to house it in. If you want to go fancy use a Goldpoint switch and Ohno continuous cast wire in an aluminum box. If you want to go bang for the buck use a Lorlin switch and some Belden shielded twisted pair cable like we use. Wiring it up is pretty straightforward, the four pole switch gives you a hot and cold pole for each channel, so you switch signal and ground at the same time - that helps to avoid ground loops and popping.

 

[denti alligator]

Great idea, Doc, except that I'm a pathetic novice and would need someone to tell me step by step what to do. Just trying to find the Lorlin switch you mention is no easy feat for me (in fact, I failed at it).

For now I'm just going to manually switch out the cables...

 

[Brillo]

The folks at Goldpoint actually offer a couple switching devices pre-built.  They're not particularly cheap, but they appear to be high-quality pieces.  Worth a peak - perhaps they'll fit the bill.

 

[Grainger49]

My suggestion is to buy the $10 switcher and try it.  It shouldn't have really harm the sound.  But if it does you have only wasted a little cash.  The second one for $20 is not going to be hugely better, probably not worse either.

 

[JC]

Or, look for something in that price range at Radio Shack or Best Buy.  Then, if you thought it was unacceptably detrimental to the sound, you would at least be able to return it somewhat conveniently.

 

[bobster]

If I understand, this should be a non-shorting switch - something like this http://www.ace4parts.com/Products/4-Pole--3-Position--Non-Shorting---Rotary-Switch__30-15403.aspx - for making my own?

 

[InfernoSTi]

Three makes it a bit trickier but not bad.  If you had two, you could use a 4PDT toggle switch which is really easy.  On those, the center is where you connect the input and either side you just match up top to bottom and that is A/B. Just remember to put the left position outside on the right on the inside or it will appear backwards when you switch (this makes sense when you have it in front of you). 

For a rotary switch, you have to think in terms of pieces of pie with the circle divided into four pieces of pie and the center being the input switching to each of the four areas. As the switch rotates from 1 to 2 to 3, it moves each of the four center connections to the corresponding connection, so all the #1s are on at once, or all the #2s are on, or all the #3s are on.  Here is a diagram that helps you think about it graphically. 

Here is a rotary switch you could look at (others have been posted that are less expensive):
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=CKC7008-ND

I say go for it and post up if you have trouble figuring it out!

 

[bainjs]

Sam:

I used this switch from Radio Shack for my Quickie: http://www.radioshack.com/product/index.jsp?productId=2062536

By the time it was finished probably $15 - $20 was spent. To your concern for quality, I can hear no difference in the audio and even though there is a common ground, there are no pops when switching inputs.

If your interested, I'd be happy to send you the parts list and the wiring diagram. I assume you have a multimeter since you built your SEX amp. You can do this!

Joel

 

[lth1]

Sam, I have been using switches by John Broskie in most of my reciently built projects .  They are extremely easy to hook up due to the excellent quality PCB.  Highly recommend!!!

http://glass-ware.stores.yahoo.net/inseswandpcb.html

Cordially,
Lee Hankins

 

[Wrinkles]

Joel,

It has been a while since I visited The Bottlehead Forum. Shame on me.

I am interested in your list of materials and wiring diagram.

Would you please send a copy to me?

Thankyou,
Wrinkles

 

[Maxwell_E]

I'm repeating a previous question, but would a shorting or non-shorting switch be preferable?

 

[Grainger49]

Non-shorting.  That could damage a source.  

You might go with make before break, it keeps down noise.

 

[JC]

Yes, make-before-break is what you're looking for in an input selector.  At least, that's the way I've always understood it.  You don't want it to short any sources, but you also want to avoid a momentary "open" input on an amp while moving the switch from one source to the next.  I would think this might be a particularly  undesirable state if you are switching grounds as well as signals, but I have never actually tried that part.

 

[Maxwell_E]

Ok, we haven't covered this in EE250 yet, but shorting switches are the same as make-before-break?

 

[JC]

Well, that's the way I learned it, anyway.

If you care to spend some time, the link has a lot of info:

http://www.electro-nc.com/faq.shtml

 

[Paul Joppa]

In the parts catalogs, shorting (S) and nonshorting (NS) refer to make-before-break and make-after-break respectively. I am not aware of a different specific term for switches that short unused inputs; that might not be good for the source device. Sometimes source selectors are arranged with an extra step between sources, which is grounded - this provides a bit of shielding between adjacent sources to prevent signal leakage. I don't think there's an unequivocal choice of switch type; at least I can think of potential disadvantages to every arrangement I can imagine.

 

[JC]

Oh, thank goodness someone else has it the same!  When it comes to nomenclature and descriptions, I'm never sure that there isn't an opposing "school" of thought!

You know, my formerly tall stack of parts catalogs has dwindled over the years because of the internet, but I often turned to them for just such questions.  I'm glad to see that at least some parts manufacturers are keeping the information tradition alive in their electronic publishing.

IOW, I picked up a couple of tidbits browsing the link I hung up above, and I'm an old guy!