Converting an older Receiver with spring loaded speaker terminals to RCA?

[mandrix]

I have a Sherwood RD6105 I bought many years ago, 5.1 analog input. Still works great.
I use it to power my four height speakers, preamped from the Onkyo. Of course the inputs are RCA, no problem there.

But the speaker terminals are those crappy spring loaded type: you know, push the spring handle up, stick the wire in, release.

What I'm currently doing is using those RCA > pin terminals to connect to the speaker terminals and then on to the RCA pre outs on the Onkyo. Because of the close proximity of the terminals I have the external connectors covered in shrink wrap to prevent any shorts.
But I have swung the unit around a few times and have had the spring terminals "let go".

I have not had the cabinet off in a long time so don't recall how it looks in the back where the speaker terminals are.

Just wondering if anyone has done something like this? Or best let it go and live with it like it is?

 

[jimfisheye]

Are you saying that you repurposed some rca connector center pins and soldered those to speaker cables to connect to your spring loaded speaker terminals? Perhaps for an easier insertion and to avoid frayed wire ends potentially shorting out?

I'd have to look at those spring loaded clips...
It might be the case that raw unsoldered copper wire smushes (technical term) into the connector and makes more surface contact than the rigid pin that ends up clamped by two pin points. I've even seen instructions in manuals recommending not solder tinning cable ends because of that concern.

After that the only concern might be if a rca jack was repurposed for an amplified speaker output like 1/4" often are. Just because it's intuitive to assume rca will always be not just line level but the lower level -10 line level. And then... surprise! Amplified power!

 

[mandrix]

Are you saying that you repurposed some rca connector center pins and soldered those to speaker cables to connect to your spring loaded speaker terminals? Perhaps for an easier insertion and to avoid frayed wire ends potentially shorting out?

I'd have to look at those spring loaded clips...
It might be the case that raw unsoldered copper wire smushes (technical term) into the connector and makes more surface contact than the rigid pin that ends up clamped by two pin points. I've even seen instructions in manuals recommending not solder tinning cable ends because of that concern.

After that the only concern might be if a rca jack was repurposed for an amplified speaker output like 1/4" often are. Just because it's intuitive to assume rca will always be not just line level but the lower level -10 line level. And then... surprise! Amplified power!

I use those RCA > pin converters. The pin end in the speaker terminal on the receiver. The other end is female RCA that I plug my speaker cable's RCA male jack into.

But you may well be right about actual speaker wire making better contact.
I guess I could just attach the speaker wire to RCA female plugs and go that route.

 

[mandrix]

The pin adapters look like these except have female RCA plugs built into them.
https://www.amazon.com/Speaker-Plated-Connector-Amplifier-Subwoofer/dp/B08G8F461N/ref=sr_1_1?crid=3BM1IZO0AZ0E4&dib=eyJ2IjoiMSJ9.Z1wPkC1fMycCPic7CmoF8IwaFv4hW7-VVjqiuJflvqACjb2MJYAvPGkfEfijJIZM_4XBmWyzxGqCaKpmzF3FalsyMs_C6E-0VVEyKZqlVTxLF6ZTrsJDBc4kCPawT-a8GZOxiYTzPsDQPJjN5hiMo5Ntj_zbMceuRrEEn1LPekpjK17FDmEQlkN18ZPUYV7B1FQQXFBEdHBdXq1D8PAAFHJ_CQSdkkCFOn3mqtfNRIU.K6UYRMinNdho4_LLnip7uJPqsBrggZR_EoylkGGwGsE&dib_tag=se&keywords=rca+to+pin+connector&qid=1735503526&sprefix=rca+to+pin+connector,aps,120&sr=8-1&th=1

 

[barfle]

I would never use RCAs for anything over about five watts. If you’re heaven-bent on replacing the spring terminals, use five-way binding posts. Those accept banana plugs, spade lugs, bare wire through holes that can be clamped, and more. They are adequate for several hundred watts.a

No doubt, some metal surgery will be required.

 

[mandrix]

In the end I just wired up some female banana plugs, and stuck the bare wire into the spring contacts on the receiver.
All my speaker wires have male banana plugs.
Would tinning the bare wires really throw that much resistance into the mix? I mean I guess I could do a test case and get out the meter.

 

[par4ken]

I've seen Banana jack speaker terminal sets on eBay that are made to replace the spring loaded ones, so you might look there.

RCAs were widely used as speaker terminals in the sixties and early seventies but usually on more budget equipment. The reason quoted for not using them is that one could inadvertently plug your expensive phono cartridge into the speaker outputs by mistake and burn it up. I still see those old speakers in thrift stores complete with RCA plugs on the end of the speaker cable.

I actually like the screw terminals often found on old and especially on tube equipment. They are less convenient to use but provide a very secure connection. I like to crimp fork terminals of the proper size to the wire ends first, then just tighten the screw.

 

[mandrix]

I believe my AVR has those banana plugs that also screw out/in. I suppose one could stick a terminal underneath. I just make adjustments to the banana plugs if needed for a good secure fit.

 

[audiomaster]

I have a Sherwood RD6105 I bought many years ago, 5.1 analog input. Still works great.
I use it to power my four height speakers, preamped from the Onkyo. Of course the inputs are RCA, no problem there.

But the speaker terminals are those crappy spring loaded type: you know, push the spring handle up, stick the wire in, release.

What I'm currently doing is using those RCA > pin terminals to connect to the speaker terminals and then on to the RCA pre outs on the Onkyo. Because of the close proximity of the terminals I have the external connectors covered in shrink wrap to prevent any shorts.
But I have swung the unit around a few times and have had the spring terminals "let go".

I have not had the cabinet off in a long time so don't recall how it looks in the back where the speaker terminals are.

Just wondering if anyone has done something like this? Or best let it go and live with it like it is?

Use fine stranded wire. About #16 gauge. Then try to fold over the last 1/8th inch of the bare wire back on itself and stuff that in the connector. That provides a bigger wire "bundle" for the inside of the connector and the folded back end will hopefully catch on the inside of the connector and help hold it in.

 

[jimfisheye]

Would tinning the bare wires really throw that much resistance into the mix? I mean I guess I could do a test case and get out the meter.

The point is that or a pin would be rigid. The spring clamp would end up contacting on two pin points of the rigid cylinder of the pin or soldered wire end. Whereas the bare wire would bend around the spring clamp metal and have more surface area contact.

That was my first concern. Secondary would be the potential surprise of amplified speaker level in a rca jack for anyone else coming across it.

 

[mandrix]

Use fine stranded wire. About #16 gauge. Then try to fold over the last 1/8th inch of the bare wire back on itself and stuff that in the connector. That provides a bigger wire "bundle" for the inside of the connector and the folded back end will hopefully catch on the inside of the connector and help hold it in.

Actually I did it with 14 gauge. Was a real pita to get in the banana plug though.
I hunted for some 16 gauge around the house but all I found was some really thin stuff, gauge unknown. I decided to skip the smaller stuff.

 

[Mackspower]

I have a Sherwood RD6105 I bought many years ago, 5.1 analog input. Still works great.
I use it to power my four height speakers, preamped from the Onkyo. Of course the inputs are RCA, no problem there.

But the speaker terminals are those crappy spring loaded type: you know, push the spring handle up, stick the wire in, release.

What I'm currently doing is using those RCA > pin terminals to connect to the speaker terminals and then on to the RCA pre outs on the Onkyo. Because of the close proximity of the terminals I have the external connectors covered in shrink wrap to prevent any shorts.
But I have swung the unit around a few times and have had the spring terminals "let go".

I have not had the cabinet off in a long time so don't recall how it looks in the back where the speaker terminals are.

Just wondering if anyone has done something like this? Or best let it go and live with it like it is?

If you're lucky, it will be a 1:1 panel replacement as shown here
DIY Youtube

 

[mandrix]

If you're lucky, it will be a 1:1 panel replacement as shown here
DIY Youtube

Now that is what I'm talking about!

Thank you so much for finding this video.

I have plenty of aluminum, as I sometimes fab pc related things. I just need to open the unit, have a good look. If it looks good I will order the binding posts.

Sweet!

 

[mandrix]

Don't know why RCA stuck in my mind when I meant banana plug. Jeez Louise.
Anyway looks like it's going to be fairly simple to do

So I bought two sets of 4 binding posts, here:

https://www.amazon.com/gp/product/B0C1Z7KD7V/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

I have some aluminum sheet, a drill press. Passable soldering skills

 

[barfle]

In the end I just wired up some female banana plugs, and stuck the bare wire into the spring contacts on the receiver.
All my speaker wires have male banana plugs.
Would tinning the bare wires really throw that much resistance into the mix? I mean I guess I could do a test case and get out the meter.

I would be surprised if a meter could tell if a wire was tinned or not. Any resistance difference would be negligible.

And, to be honest, iI wouldn’t add another set of connections in the speaker lines. They might add a bit of convenience if you’re changing things around a lot. Otherwise, they’re just another connection the current has to run through, and another potential failure node. Keep it simple if you can.

 

[barfle]

Don't know why RCA stuck in my mind when I meant banana plug. Jeez Louise.
Anyway looks like it's going to be fairly simple to do

So I bought two sets of 4 binding posts, here:

https://www.amazon.com/gp/product/B0C1Z7KD7V/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

I have some aluminum sheet, a drill press. Passable soldering skills

Now this looks a lot like what I recommended. Yeah, confusing RCAs and 5-ways confused me, too. I think this will work well. Show us some pictures when it’s done, please.

 

[jimfisheye]

I would be surprised if a meter could tell if a wire was tinned or not. Any resistance difference would be negligible.

It's not the resistance of the solder. It's turning the wire end into a rigid cylindrical pin. The spring clamp is two flat edges that clamp the wire. Two flat edges only contact a cylinder on two pin points. It's that reduction of the conductor mass in that spot that acts like a resistor.

Now there are different spring clips and some of them have larger surface area contact. But the cheap ones exist and that would be the maybe not obvious at a glance concern.

Banana plugs are good for speaker connections! Recognized as the speaker plug looking connector and everything. +1 to that

If you want a super power with electronics, computers, and anything that needs wires connected? Recognize that these connections are not trivial and use the proper wires and connections. Shielding. Ground draining. Follow the design and don't alter it with substitutes.

Treat the cables and connectors like the most delicate equipment you own. Don't treat cables like rope and put any tension on them! That means no coiling like rope with little tugs and tight coils. 99/100 of the first failures or weird and intermittent malfunctions are some connection failing. Treat your cables and connectors religiously and 30 years of heavy use later... everything still just works like always.

 

[audiomaster]

Actually I did it with 14 gauge. Was a real pita to get in the banana plug though.
I hunted for some 16 gauge around the house but all I found was some really thin stuff, gauge unknown. I decided to skip the smaller stuff.

Remember in this situation, unlike AC power, you are not really concerned about the maximum current carrying capacity of the wire or connctor, but about the total wires loop resistance, which is likely to be greater than the contact resistance at the connector. This affects power transfer as well as the ability of the amplifier to "damp" or control the cones bass transients. So 4 ohms of wire resistance driving a 4 ohm speaker means you are losing half the power in the wire! 1 ohm of wire resistance driving an 8 ohm speaker is much more desirable. 0.1 ohm wire driving a 16 ohm speaker becomes almost insignificant in terms of power loss. Particularly as watts are relatively cheap these days.

 

[Jeff ss]

I have a Sherwood RD6105 I bought many years ago, 5.1 analog input. Still works great.
I use it to power my four height speakers, preamped from the Onkyo. Of course the inputs are RCA, no problem there.

But the speaker terminals are those crappy spring loaded type: you know, push the spring handle up, stick the wire in, release.

What I'm currently doing is using those RCA > pin terminals to connect to the speaker terminals and then on to the RCA pre outs on the Onkyo. Because of the close proximity of the terminals I have the external connectors covered in shrink wrap to prevent any shorts.
But I have swung the unit around a few times and have had the spring terminals "let go".

I have not had the cabinet off in a long time so don't recall how it looks in the back where the speaker terminals are.

Just wondering if anyone has done something like this? Or best let it go and live with it like it is?

If your speaker wires have banana jacks, you could use these. I use them on my tube amps that have a screw terminal.

https://www.parts-express.com/Lil-P...ire-Adapter-Set-Red-and-B-091-1262?quantity=1

 

[mandrix]

Guys the plan is in place and I linked the binding posts I bought in post 14.
Might get to the plan this weekend, or at least after the posts arrive.
I will be removing the plate the current speaker terminals are in and fabbing a new plate out of aluminum sheet and installing the binding posts in it...desoldering the old ones and soldering in the new ones..

Appreciate all the feedback.