We like all kind of approaches in gear and we are happy seeing different systems and learning the results. That is why I designed in the FSP a wide sensitivity configuration ability from the start. We had enough builds for MM here. Good luck in building it and keep us updated.
I've been through several of the older Shure carts over the past 20 years, and am now using their new flagship, the N97xE. I don't hear any reason to imagine that the quality isn't what it used to be back in the 1970s, but others are still convinced that the older ones are better.
I have read (from an article Salas linked me to) that these new N97xE ones may occasionally fail to meet Shure aficionados' expectations because they require higher/ different input resistance/ capacitance, which I'll have control over with the FSP, so all should be good.
I've heard great things about the Jico styli, and will maybe get one when this Shure one wears out.
Here's the article on MM input loading, which is very much ON topic as it provides good reason for MM users to build this design, as the variable input resistance loading is critical to getting a MM cart working as it should...
Load the Magnets!!! - [English]
Load the Magnets!!! - [English]
Step by step building is always the most careful approach but keep in mind that Q6x will share no current to a load yet so its sink will appear double hotter than normal later on. About 3.5W VS 1.75W. It will still hold well for relatively quick testing so to check that the CCS current is about 100mA and the output range varies sufficiently between 30 and 37V by VR2x. In case its not you will need a different value R3x etc.
Try find the most linear most low noise most high HFE matched transistors pair pin compatible with Q3Y or Q3Z instead. Elusive NEC TOSHIBA HITACHI PHILIPS of yore. Rare birds, and fakes all around, kind of a holy grail quest. Those are the heart of the input stage's voltage signal translation. A more "productive" and adventurous subtleness tweak.
Since "it is not that bad idea" to try to use big PP in addition to C8 (in my case Nichicon KZ 470uF) Ele cap, I'm also willing to try it. I'm finishing my second FSP with significant dedication to the matching and ClarityCaps (C3&C4) instead of Mutdorfs Supreme SiO in my first FSP.
Any advice for Big PP caps? Space limitation is also quite concern and I see ACS has dry Metalized Polypropylene Film Capacitors (80uF 330VAC in Partsconnexion for $14.95).
Is it good enough to try or PP Oil filled is better choice?
Any advice for Big PP caps? Space limitation is also quite concern and I see ACS has dry Metalized Polypropylene Film Capacitors (80uF 330VAC in Partsconnexion for $14.95).
Is it good enough to try or PP Oil filled is better choice?
Attachments
Looks great Alex. What are the red boards? They look like shunt regs, but that doesn't make too much sense to me, as I can see that you're using the onboard Salas regs.
Thank you salas
P.S. Also check that the originally missing 47 Ohm R8 that was found as 47K and fixed did not accidentally end up as R1 or R14. Disconnect the TT from the L&R phono inputs, don't turn the power on, and measure with the DMM across each input to confirm the expected load resistors values. When all the DIP switch positions are set to OFF it should read 47K. Measuring across R14 it should read 47K too.
Its not bad in general to mix those two types but not that productive in FSP giving rather subtle contentious changes especially when the widening of layout area it takes by projecting routes away from the board can make it prone to picking interference etc. But if you are to tweak parts and see for yourself its not destructive or non reversible. PP Oil is good but keep it away from heated areas. PP straight is OK. The main value will be coming from the Elco so why not alternatively try some different elcos that catch your fancy either alone or in PP combo.
I used the ASC oils because they are inexpensive and many have found them to work well. I got mine from an EBAY seller at a very good price. They are the smaller diameter version which made them much easier to situate.
Placing them below the board, and with the board on "stilts" makes for easy installation though impossible to place the finished circuit in any easily obtainable enclosure. My phono is out in the open. I have placed a balsa enclosure around the board to collect some heat but the reg heat sinks are barely above warm. Would be warmer in the summer.
There is no heat being transferred to the "cans".
In many ways an axial capacitor will be more difficult to use. I know nothing about the ASC PPs though I suspect they are great motor run caps.
I am not trying to say this use of the ASCs has been decisive. It certainly does no harm and I figure has to be better but doing this will not bring about audio enlightenment. It is more trouble than it is worth to go back and forth so I cannot give you any definite differences.
I know these caps made a big difference in the raw supply along with that rectifier but my raw supply has nothing to do with the recommended supply so a comparison there has not been made. I took it on faith that a choke input supply would be superior and that is why I can get by with so little capacitance in the raw supply.
As far as a mod that I can assure you makes a real sonic improvement, use the Yazaki recommended rectifier, STTH6110TV2, a low R choke, I am using 5 Hys/25R and the ASC caps. I am using 150 uF but will eventually add more just to be sure. Not a bridged rectifier, just a standard full wave. I like the simplicity and the non-floating ground.
I found I had to tune each supply to get the voltage needed for each board. Using a small input cap and a low value high power resistor as a bleeder to get what each board required. The boards were tested with a lab supply which did not care about the differences since it is a regulated supply. If you tuned your phono circuit with an unregulated supply then this will likely not matter and you can use the same values for each channel. I like the idea of a bleeder that forces the raw supply to work. Yes, it is inefficient. It will require larger than usual transformers. I prefer EI over toroids.
I can assure you the rectifier and ASC cans in the power supply is close to amazing. A difference that will not strain your ears to hear. it will be immediately obvious. If your experience is like mine you will think you are dreaming and are suffering from an extreme case of BARANEK's LAW (the one that no loudspeaker ever sounds as good as the one you have made for yourself). But as the days pass by you can assure yourself something very good has happened.
I would try something like that first. After hearing those effects I decided to carry the idea over to the SILMICs on the board but at this point I cannot assure you that has made a big difference. Nonetheless, if you like what the raw supply mod does you might want to do it just to relieve yourself of wondering just what kind of difference it would make. Yes, that is an admission of serious DIY audiophile psychosis.
The raw supply shown in the guide is not an above all recommendation
Of course there is potential for personalized expensive/bulky raw supplies and its an experimentation area left open to the more adventurous builders
Quoting from the guide:
"More elaborate and costly PSUS are up to you. The basic one shown in pic2 is satisfactory enough"
Of course there is potential for personalized expensive/bulky raw supplies and its an experimentation area left open to the more adventurous builders
Quoting from the guide:
"More elaborate and costly PSUS are up to you. The basic one shown in pic2 is satisfactory enough"