Looks like you set the spacing between the two RCAs and solder the 3 tabs on each to the board.
I haven't used those type of input boards before, but the point is that it makes the connection to an amp a bit easier. I believe you are supposed the solder the jack lugs onto the little PCB. It looks like it is designed to allow for adjustable spacing between the jacks. Quiet clever IMO. Were did you get it?
Hi redj- The thing about soldering the jack lugs is that there is quite a big gap to fill. Would you only solder one side of the jack lugs.
I got the jacks, board and cable from YJ audio when I ordered the blue board.
cheers
I got the jacks, board and cable from YJ audio when I ordered the blue board.
cheers
To buy or not to buy that is the question...
I have a unmodified red board. Is worth to buy the blue one or not? Has anyone compared the unmodified red and blue and what are the differences?
Red YJ with a linear power supply has a great sound, better than with really good laptop variable power supply. My system is WDTV (flac) + Lampucera (slightly modified) + red YJ amp + Fostex fe207e and ft17h speakers.
I have a unmodified red board. Is worth to buy the blue one or not? Has anyone compared the unmodified red and blue and what are the differences?
Red YJ with a linear power supply has a great sound, better than with really good laptop variable power supply. My system is WDTV (flac) + Lampucera (slightly modified) + red YJ amp + Fostex fe207e and ft17h speakers.
You wire the L and R inputs from your source (i.e the wires from your RCA connectors) to the pot as you would normally do in any amp and then you take the outputs from the pot (L, R and G) and wire them either directly to the appropriate pins on the 3-pin input header or you can connect them to a 3-pin plug salvaged from an old PC fan or similar and then connect that to the header.
Saturnus,
I've thinking about something ever since you posted about the need to sync board clocks.
In your earlier posts, you have shown how a ferrite bead type of filter is best for these amps as opposed to the inductors used on the boards.
As you also clarified, this means that speaker cable length should be shorter than 1m max, which means an active speaker type of application.
Now on the other hand, we need to sync these boards if we want to avoid low freq noise (I know this is not the right word, but I hope you get what I mean), and syncing boards means connecting pins between boards, meaning short distance between boards (less than a few cm I guess?)
Does this not mean that we have to choose between sync'ed boards or ferrite filter?
What in your opinion is the lesser of two evils?
I've thinking about something ever since you posted about the need to sync board clocks.
In your earlier posts, you have shown how a ferrite bead type of filter is best for these amps as opposed to the inductors used on the boards.
As you also clarified, this means that speaker cable length should be shorter than 1m max, which means an active speaker type of application.
Now on the other hand, we need to sync these boards if we want to avoid low freq noise (I know this is not the right word, but I hope you get what I mean), and syncing boards means connecting pins between boards, meaning short distance between boards (less than a few cm I guess?)
Does this not mean that we have to choose between sync'ed boards or ferrite filter?
What in your opinion is the lesser of two evils?
hajj, I'm not Staurnus, but if boards are that far away and powered from different supply they do not need sync indeed. I mean if we talk about active speakers.
Just checking if I understand things right:
In order to avoid the need to sync the boards, one needs to power each board from its own PS?
Thanks
hajj, generally I'm of the opinion that active speakers or at least separate amplifiers for each speaker is the correct way to use these boards. Sure, it adds the need for an additional power supply but it avoids the use of long speakers cables. In such a scenario there is only need for sync'ing different boards relating to each separate speaker. So if you have a 2-way speaker for example it would not be necessary to use more than one amplifier board unless you prefer them to be PBTL'ed.
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Sync needed if boards are in close proximity thus having electromagnetic interference and/or shared supply lines. If they are far away (each in its own housing and with separate supply) syncing is not need.
If you share same housing syncing is an easy way as otherwise you need extra shielding and separate PS or at least very good power lines filtering.
Correct. And add physical distance as well. Place the amplifier driving each speaker as close to the speaker as possible if not built directly into it.
Saturnus, McDark,
Thanks for the detailed replies.
Time to start my build now.
I've been gathering a galore of these amps and will start with the YJ red boards in active full-range monitors and see how that goes 🙂
Just counted the amps I have, I'm at 12 and counting (ranging from SET to Class D and a sprinkling of Class A SS....) One can't have too many amps, right? 😀
Thanks for the detailed replies.
Time to start my build now.
I've been gathering a galore of these amps and will start with the YJ red boards in active full-range monitors and see how that goes 🙂
Just counted the amps I have, I'm at 12 and counting (ranging from SET to Class D and a sprinkling of Class A SS....) One can't have too many amps, right? 😀
I would think soldering one side would be sufficient, but I'd have to see how secure it would be with a normal amount of solder. Even if the gap is a little wider you should be able to flow enough solder around the pins to the solder pads. If the solder pads go through the hole to the other side (which I presume they do), than you could solder that too and make an even stronger joint. (whoops, that was bad choice of words. 🙂 ) Not sure if you would need it though. You just want to make sure you've got a good, solid solder connection. I'll have to check them out.
I thought he gave up on that since he is selling the blue YJ board at his site. Hmmm, looks interesting (very compact). Thanks wushuliu.
Regards,
There's a DIY kit on Ebay, as well. That's got appeal except their's so little room for choosing your own input caps. The blue board is nearly better given the fact you can even figure out ways to get longer leads of film caps to actually reach the board. (not that you want long leads, but let's not kid ourselves, Teflon's are better). Good thing I like a little recipe no one seems to care about or take seriously, yet.
But again, how many of these things do I have to order! I'd rather be the supplier of the chip itself at this point.
That brings me to another point. I don't believe DIY kits should ever NOT solder on little SM chips. The TPA3116, TPA3110, and other things like PCM chips for DAC's. It's not that I can't, it's that it takes the manufcaturer/seller a brief moment to have it done in process, an effortless breath, and the rest of us tooling around with flow additive or small tipped irons with skill with a much, much greater risk of ruining the board or chip. It's not that big of a deal for me, but it's no a deal at all for them.
But again, how many of these things do I have to order! I'd rather be the supplier of the chip itself at this point.
That brings me to another point. I don't believe DIY kits should ever NOT solder on little SM chips. The TPA3116, TPA3110, and other things like PCM chips for DAC's. It's not that I can't, it's that it takes the manufcaturer/seller a brief moment to have it done in process, an effortless breath, and the rest of us tooling around with flow additive or small tipped irons with skill with a much, much greater risk of ruining the board or chip. It's not that big of a deal for me, but it's no a deal at all for them.
I agree 100%. I like to solder, but SMD chips? Why bother when they can be done in the process for .05 more. It's a no brainer in my opinion. Luckily, a lot of the monolithic IC amp boards and other PCB from eBay sellers include the SMD parts already solder on. Suits me just fine. 🙂