4x RCA to HDMI for Quadraphonic Record Player / Quad Demodulator to Use On HDMI Only System

QuadraphonicQuad

Help Support QuadraphonicQuad:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Well... Here we go. Parts finally came in to put this thing together. I'm just getting started and I already nicked my thumb. Probably going to wind up with a biohazard band sticker on the front of this thing by the time I'm done with it!
 

Attachments

  • PXL_20230310_015930424.jpg
    PXL_20230310_015930424.jpg
    1.3 MB · Views: 0
Well... Here we go. Parts finally came in to put this thing together. I'm just getting started and I already nicked my thumb. Probably going to wind up with a biohazard band sticker on the front of this thing by the time I'm done with it!
Half way there! 2 hours in, my fingers are getting tore up from the wire cutter crimping and stripping. About 24 feet of AWG 12 going into this little box. Left room at the top for an RCA switch to a subwoofer. Will basically flip 3 switches to go from one amp to the other.
 

Attachments

  • PXL_20230310_055609627.jpg
    PXL_20230310_055609627.jpg
    997 KB · Views: 0
  • PXL_20230310_055607216.jpg
    PXL_20230310_055607216.jpg
    1.2 MB · Views: 0
Nice!

I have a very similar box that dates came in. From Global Market in Kirkwood.

I think you are accomplishing what you set out to, in about the best way possible. Short of having four extry spikkers.
 
Last edited:
Half way there! 2 hours in, my fingers are getting tore up from the wire cutter crimping and stripping. About 24 feet of AWG 12 going into this little box. Left room at the top for an RCA switch to a subwoofer. Will basically flip 3 switches to go from one amp to the other.
You just need a good wire stripper. I have several myself. I make up all my wiring custom on my pc's, crimp the terminals, and sleeve the wiring. 18 gauge for the psu and 22 gauge for fan wiring.
A good wire stripper doesn't cost much. I have one that lets you set the length of the strip, and one that doesn't. (and a specialized crimper for the molex terminals)

Anyway, is that the black box that is going to let you convert analog to HDMI?
If so I missed what you were going to use to accomplish that.
 
I have been told that doing multiple AD/DA conversions degrades the audio signal. Since the Surround Master is doing it's audio processing in digital and then converting to analog to output the 4-6 analog channels, is it a good idea to make the HDMI output on a separate box that then has to convert the signal back to digital again to output over HDMI? Wouldn't it be better to just send the multi-channel signal strait out an HDMI?

The only reason to do it external that I can think of is the ability to use with other legacy gear, but the quality of the converters is a concern. People with high end equipment that contain really nice DAC's would prefer to have the HDMI output on the Surround Master to let their equipment to the conversion.

Since there are so many great USB DAC's out on the market I wonder why receiver manufactures aren't developing USB interfaces that could send the audio streams between devices. Even a USB to HDMI that could connect to a USB interface on the Surround Master. It would be nice if they could develop this and force HDMI to drop or reduce the fees. There are plenty of PC USB to HDMI adapters on Amazon, maybe someone could build a board/chip that would go in the Surround Master that could interface with the USB adapter to send the audio signal out over it. The PC adapters are pretty cheap.
 
Half way there! 2 hours in, my fingers are getting tore up from the wire cutter crimping and stripping. About 24 feet of AWG 12 going into this little box. Left room at the top for an RCA switch to a subwoofer. Will basically flip 3 switches to go from one amp to the other.
Echoing @boondocks, good tools are a must. When Imwas a kid, I thought there was some sort of magic to soldering. Then I went through a class with a good soldering iron, and have made tens of thousands of solder joints since then.

Same with stripping wires and crimping lugs. The right tool makes life a lot easier.
 
I have been told that doing multiple AD/DA conversions degrades the audio signal. Since the Surround Master is doing it's audio processing in digital and then converting to analog to output the 4-6 analog channels, is it a good idea to make the HDMI output on a separate box that then has to convert the signal back to digital again to output over HDMI? Wouldn't it be better to just send the multi-channel signal strait out an HDMI?

The only reason to do it external that I can think of is the ability to use with other legacy gear, but the quality of the converters is a concern. People with high end equipment that contain really nice DAC's would prefer to have the HDMI output on the Surround Master to let their equipment to the conversion.

Since there are so many great USB DAC's out on the market I wonder why receiver manufactures aren't developing USB interfaces that could send the audio streams between devices. Even a USB to HDMI that could connect to a USB interface on the Surround Master. It would be nice if they could develop this and force HDMI to drop or reduce the fees. There are plenty of PC USB to HDMI adapters on Amazon, maybe someone could build a board/chip that would go in the Surround Master that could interface with the USB adapter to send the audio signal out over it. The PC adapters are pretty cheap.
As I understand, and I was certainly not involved with Involve’s design team, the digital parts are determining the parameters that operate the analog path. But Chucky could expound on this at length.
 
Here in St. Louis where Dude Rocks lives and I too we had , for 60 years "Gateway Electronics" a wonderful surplus electronics place where you could buy all kinds of wonderful tools for electronics construction. I started going there when they opened. However the pandemic caused the coup de grace which began when the two founders passed away and their respective widow wanted their share NOW! Of course you can buy strippers and crimpers online but it't not the same as a place you can go on saturday and hang out with other electronic morons. All the electronic hobbies were very well represented there. I started going there right when they opened and also hauled lots of stuff out when they were closing. Like real hifi stores, sorely missed.
 
You just need a good wire stripper. I have several myself. I make up all my wiring custom on my pc's, crimp the terminals, and sleeve the wiring. 18 gauge for the psu and 22 gauge for fan wiring.
A good wire stripper doesn't cost much. I have one that lets you set the length of the strip, and one that doesn't. (and a specialized crimper for the molex terminals)

Anyway, is that the black box that is going to let you convert analog to HDMI?
If so I missed what you were going to use to accomplish that.
No luck finding a premade item that converts MCH RCA to HDMI. This is a workaround hopefully it will help others who need to do something similar. Rather than sending a signal over HDMI to another amp to output through the speakers, I'm routing the second amp direct into the speakers.
 
Here's some pics of all the tools that I used. I ordered a new wire stripper, not sure what to name her yet. My old one in the picture is the Black B... since it tears your hand up more than it actually crimps wire, probably one of those freebies you get in a kit.

Items purchased online and tools:
100Pcs 12-10AWG Insulated Terminals Ring Electrical Wire Crimp Connectors (Yellow, M4) (12-10AWG)
100Pcs 12-10AWG Insulated Terminals Ring Electrical Wire Crimp Connectors (Yellow, M6) (12-10AWG)

The M4 for for switch, the M6 for the terminals.

Speaker wire switches search for 4PDT Lacthing Rocker Toggle Switch Heavy-Duty 15A 250V 12P ON/Off/ON Metal Bat 2pcs
The key here is the Off as it will completely cut the link between one amp before joining the other. I used a 9/16 crescent to get the screw down for the switches on the top but couldn't put the wrench handle on because the switch was poking up in it so I just had to hand tighten it.

2x sets of 18 Pcs Speaker Terminal Binding Post Power Amplifier Dual 2-Way Banana Plug Jack(6pcs)+ Red and Black Gold Plated 4mm Banana Plugs(12pcs)
I have seen bad reviews on the plugs for this kit and it's possible to forgo them altogether but I'll make it a project when the new crimper comes in tomorrow.

I used a 5/16 to get the terminal screws in place. I think if I went back and did this again the first couple rows I did I put the wire side down so it wouldn't poke out and stab me while I was putting the screws on but later realized that the standoffs had a special ring that was meant for putting wire under it and after I started using the crescent wrench I avoided getting stabbed altogether. So I'm hopeful my first couple of rows will work as good as the last couple.
 

Attachments

  • PXL_20230310_204144839.jpg
    PXL_20230310_204144839.jpg
    1.3 MB · Views: 0
  • PXL_20230310_204136579.jpg
    PXL_20230310_204136579.jpg
    1.2 MB · Views: 0
  • PXL_20230310_203735556.jpg
    PXL_20230310_203735556.jpg
    887 KB · Views: 0
  • PXL_20230310_203631162.jpg
    PXL_20230310_203631162.jpg
    1.4 MB · Views: 0
Last edited:
Dude Rocks
Please do yourself a favor and throw that wire stripper/crimper tool into the trash. It is bound to happen that you will be using it and one hand will be squeezing it on the grips and the other hand will be holding your work and the fat muscle the flexes your thumb (thenar I think) will get in between there and get bitten.
You don't need to ask me how I know.:rolleyes::rolleyes: I think that style of tool should be illegal or someone should sue the pants off anyone selling them.


But nice work.
 
I think that style of tool should be illegal or someone should sue the pants off anyone selling them.
My issue with that type of tool is not ergonomic, but rather that that it is hard to get good solid reliable crimps. The ratcheting type tools are available inexpensively and produce much more reliable crimp connections. Did you know, they say that a proper crimp produces an even better connection than soldering does?

Yes, nice job! I love to see people doing these type of DIY projects!
 
Here's some pics of all the tools that I used. I ordered a new wire stripper, not sure what to name her yet. My old one in the picture is the Black B... since it tears your hand up more than it actually crimps wire, probably one of those freebies you get in a kit.

Items purchased online and tools:
100Pcs 12-10AWG Insulated Terminals Ring Electrical Wire Crimp Connectors (Yellow, M4) (12-10AWG)
100Pcs 12-10AWG Insulated Terminals Ring Electrical Wire Crimp Connectors (Yellow, M6) (12-10AWG)

The M4 for for switch, the M6 for the terminals.

Speaker wire switches search for 4PDT Lacthing Rocker Toggle Switch Heavy-Duty 15A 250V 12P ON/Off/ON Metal Bat 2pcs
The key here is the Off as it will completely cut the link between one amp before joining the other. I used a 9/16 crescent to get the screw down for the switches on the top but couldn't put the wrench handle on because the switch was poking up in it so I just had to hand tighten it.

2x sets of 18 Pcs Speaker Terminal Binding Post Power Amplifier Dual 2-Way Banana Plug Jack(6pcs)+ Red and Black Gold Plated 4mm Banana Plugs(12pcs)
I have seen bad reviews on the plugs for this kit and it's possible to forgo them altogether but I'll make it a project when the new crimper comes in tomorrow.

I used a 5/16 to get the terminal screws in place. I think if I went back and did this again the first couple rows I did I put the wire side down so it wouldn't poke out and stab me while I was putting the screws on but later realized that the standoffs had a special ring that was meant for putting wire under it and after I started using the crescent wrench I avoided getting stabbed altogether. So I'm hopeful my first couple of rows will work as good as the last couple.
Well Sir know it is a pleasure to see such nice clean wire routing and work! I think now it was worth a few drops of blood here and there.

When I took an Industrial Electronics class many years ago (DC electronics). We studied theory and had numerous tests and I remember I had a National Semiconductor calculator that used "reverse polish logic". Unlike the folks that could afford the more expensive Texas Instruments calculators.. lol. (late 70's)

Anyway, toward the end we had to build a working AM radio to demonstrate we could actually, well, make something I guess. What I do remember was half the class could not get such a simple device to work. If you looked at their solder joints and their connective wiring, it sometimes looked like a nest of snakes instead of shortest distance from point A to point B, which of course is not gemaine to your wiring necessarily, but can be in electronic circuits.
But, neatness may not make something work better, but it sure as hell makes it easier to troubleshoot!

Bravo, Sir. I love seeing people's projects realized.
 
Thanks everyone for the compliments. I'll have this tested out over the weekend! The RCA switch should come in next week or so for the subwoofer connection too. Using a pair of RCA Splitter 1 Female to 2 Male, one for the front and one for the rear, takes the signal from stereo to mono then I will route that to the left/right RCA on the sub.
 
For the 9/16" panel nuts, I use a deep well socket so the toggle fits in there. Might not fit all switches though, there are also slim crescents.
That style crimper can be alright but having been bit, I'm careful to load and hold the connector in place, hold it firmly, and push the pre stripped wire in from a couple inches back with the other hand before crimping
I take that back. I looked closer a the photo and that is a poor, dangerous crimper. As Gene said above, it should be tossed out. One mistake with that much pressure can cause lasting damage. Don't ask me how I know.

The part where the connector sits should be a C shape on one side and a bump on the other, the connector positioned so the bump indents the continuous part of the ferrule, not the ends where they meet. The crimping action should be below the hinge unless it is the better yet ratcheting type. There are better crimpers, but the kind in the picture is the worst. I mean, it can make a solid connection, but it is dangerous especially on large stuff. It just smashes, and can twist, and is hard on the hands.
Just for future reference of course, if the connectors aren;'t loose no problem.
The layout is great.
 
Dude Rocks
Please do yourself a favor and throw that wire stripper/crimper tool into the trash. It is bound to happen that you will be using it and one hand will be squeezing it on the grips and the other hand will be holding your work and the fat muscle the flexes your thumb (thenar I think) will get in between there and get bitten.
You don't need to ask me how I know.:rolleyes::rolleyes: I think that style of tool should be illegal or someone should sue the pants off anyone selling them.


But nice work.
I had a job with an A/V contractor about 30 years ago, and I got called to fix a system that had stopped working. It was about an hour and a half’s drive from our office. When I got there, after just a few minutes of troubleshooting, I discovered a ground wire on the control chassis had slipped out of its crimp lug. I used my ratcheting lugger and fixed it in two minutes, then drove back to the office.

I suggested that the company provide proper tools for the installers to prevent such profit-draining excursions, but that didn’t happen. Again, scrimping on tools is pound foolish.
 
I bought a lug kit back in the day that had a crimper stripper like that. It bit me hard and it actually could have been much harder but I was lucky and young and still had reactions. Since then I have called those out whenever I have seen them and told whomever would listen to throw them away.

Ratcheting crimpers do make a better crimp.

https://www.grainger.com/product/STA-KON-Ratchet-Crimper-10-AWG-12-4XMR5
https://www.grainger.com/product/WE...IDP_Switch_Save--Link2&sas_sku_original=4XMR5
 
Last edited:
Back
Top