Hi folks!
Was wondering if anyone had tried playing about with the values before/after the LM7808 regulator? The Shigaclone standard seems to be 1000uF - regulator - 1000uF.
Was going through the LM7808 datasheet out of interest and it mentions you only need a 0.1uF cap (ceramic disc type recommended) after the regulator. Has anyone tried this?
http://www.national.com/ds/LM/LM340.pdf
Is 1000uF really needed before the regulator too? I'd be interested in people's views/experiences with this. I'm going to try a 0.1uF tantalum cap after the regulator on my Shiga and see if it makes any difference.
- John
Was wondering if anyone had tried playing about with the values before/after the LM7808 regulator? The Shigaclone standard seems to be 1000uF - regulator - 1000uF.
Was going through the LM7808 datasheet out of interest and it mentions you only need a 0.1uF cap (ceramic disc type recommended) after the regulator. Has anyone tried this?
http://www.national.com/ds/LM/LM340.pdf
Is 1000uF really needed before the regulator too? I'd be interested in people's views/experiences with this. I'm going to try a 0.1uF tantalum cap after the regulator on my Shiga and see if it makes any difference.
- John
@ maartenje - the original Shigaraki transport is mounted at two points; Peter's experiments (later confirmed by others) indicate that it really does make the transport sound better.
@ johnm - Without the big input cap you would be feeding the entire AC ripple into the regulator, which can't be a good thing... As for the output cap, I think you could get away with a small one, but only on condition that the regulator is installed directly at the load (which is not very practical).
Sound-wise, caps lower than 1000uf seem to result in bass loss.
Oh, and the "Shigaclone standard" is actually 2200uf - reg - 1000uf
Although 1000-r-1000 works just as well most of the time. Capacitor types are more important here than exact values.
@ johnm - Without the big input cap you would be feeding the entire AC ripple into the regulator, which can't be a good thing... As for the output cap, I think you could get away with a small one, but only on condition that the regulator is installed directly at the load (which is not very practical).
Sound-wise, caps lower than 1000uf seem to result in bass loss.
Oh, and the "Shigaclone standard" is actually 2200uf - reg - 1000uf
Although 1000-r-1000 works just as well most of the time. Capacitor types are more important here than exact values.
Uncle_leon: Thanks for the explanation - I understand the need for the 1000uF (or higher) for the 'input' cap, but I don't see what could cause bass loss with using less than that at the output of the regulator, particularly when the datasheet recommends 0.1uf. As my Shigaclone is in a Peter Daniel chassis, the regulator is right next to the transport mech. I guess in this instance then I could safely experiment with smaller value caps?
Was wondering if there are any fake Sanyo transports doing the rounds out there? The first transport I took from a JVC boombox had Sanyo clearly embossed in the moulded black plastic housing which the laser is mounted in. A mechanism I got from another JVC didn't have any logo embossed into the plastic, and ditto for two Sanyo spares which I got from Ebay (and which were advertised as genuine Sanyo spare parts). Is there anyway to tell if one has the real item or not?
Cheers,
- John
Was wondering if there are any fake Sanyo transports doing the rounds out there? The first transport I took from a JVC boombox had Sanyo clearly embossed in the moulded black plastic housing which the laser is mounted in. A mechanism I got from another JVC didn't have any logo embossed into the plastic, and ditto for two Sanyo spares which I got from Ebay (and which were advertised as genuine Sanyo spare parts). Is there anyway to tell if one has the real item or not?
Cheers,
- John
@ johnm - I'm sure there is no harm in experimenting with capacitor values after the reg, please report back with your findings As to the Sanyo mechanism, I also bought one on eBay, and to be honest, the "original" mechanism has exactly the same rubbish build quality as the eBay one
@ apoopoo999 - That is one imposing CD player! Did you protect the aluminum with anything, or is it hard enough to resist scratches?
As to the Sanyo mechanism, I also bought one on eBay, and to be honest, the "original" mechanism has exactly the same rubbish build quality as the eBay one @ apoopoo999 - That is one imposing CD player!
Did you protect the aluminum with anything, or is it hard enough to resist scratches?
I have recently tested another C916 capacitor, and before you ask: no, it didn't beat the Black Gates.
But there is a very good reason why it deserves a mention nonetheless: SIZE!
Here it is, pictured here next to the Sanyo mechanism, to give you a sense of scale:
It is a 47uF/630VDC ClarityCap, and it dwarfs even smaller transformers.
Unfortunately, the old saying "size does not matter" came true on this occasion as well. The ClarityCap did have certain pleasing tonality correctness, not found in electrolytic caps - but the presentation lacked the spark and detail of BGN, and I am not even sure I would prefer it over Starget (which is currently ranked #4 in my C916 charts).
Thankfully, I can buy another one of those mastodons, and use them to upgrade my speakers' crossovers, so it was not a total waste of £42
But there is a very good reason why it deserves a mention nonetheless: SIZE!
Here it is, pictured here next to the Sanyo mechanism, to give you a sense of scale:
An externally hosted image should be here but it was not working when we last tested it.
It is a 47uF/630VDC ClarityCap, and it dwarfs even smaller transformers.
Unfortunately, the old saying "size does not matter" came true on this occasion as well. The ClarityCap did have certain pleasing tonality correctness, not found in electrolytic caps - but the presentation lacked the spark and detail of BGN, and I am not even sure I would prefer it over Starget (which is currently ranked #4 in my C916 charts).
Thankfully, I can buy another one of those mastodons, and use them to upgrade my speakers' crossovers, so it was not a total waste of £42
What you are saying then, amounts to "don't bother", and I see it as rather unappreciative. Yes, it is easier, and A LOT cheaper to just follow the advice of others who did the hard work for you. But I wanted to give something back, so people could have better sound for less, that's why I spent all that time and money - pointlessly as you are suggesting.
If you want to help, then sell me a couple of your regulators, and I'll see if I can make cheap PCBs for them, or organise kits or something, so everyone can benefit.
And then, of course, I'll see if I can find better capacitors for them
If you want to help, then sell me a couple of your regulators, and I'll see if I can make cheap PCBs for them, or organise kits or something, so everyone can benefit.
And then, of course, I'll see if I can find better capacitors for them