Thanks for the explanation. Apparently there is no lack of stuff for me to still learn
Having second thoughts about using two SIO in series... one is maybe ok, but two bring up the rather unpleasant character of the SiO i had nearly forgotten. Sadly, my entire supply of Clarity MR is already utilised elsewhere... I need a slightly warmer and more bass friendly output cap.
Cool thanks George. Anoderesistor to a lightly loaded 12AX7 dissipates less then 0,1 W so a 0,25 would probably be alrighty.
Not yet. Farnell is the only place where i can get next day delivery and they only seem to stock copper plated steel coax. So, its off to ebay and January
And rounding it off a bit won't help enough. My other phono pres are wired the same way, yet the bass is in a different league. Which i mostly attribute to the SiO.
No, at least not initially. I'm going to use the 100R VAR as R1 and leave out the switch and Rxn resistors. If I ever get another MC cartridge that needs different loading I'll move R1 to R1x and populate the rest. For now this gets me the loading I want, lowers the cost a bit, removes the switch entirely, and allows me to terminate the input cables closer to the 369's.You mean Rx1 is 100R and R1/R14 are 47K reapectively? All 3 are Vishay VAR.
Bass is excellent with 3.3uF SIO and 0.047uF teflons. Stonger and more defined. It was one of the firsts things I noticed, comparing to the point to point version I had. Also in general noise was lower. Maybe box it first and then start desoldering things.
Also I thought of another possibility for perceived weak bass. Have you balance levels with an SPL meter before comparison? Maybe midrange is at lower level and bass is emphasized.
Boards are now ready for powering up!
I used polystyrene ERO kp1834 5% for the treble RIAA cap plus trim cap which gave me a value of 15.18nf and 15.15nf. Readings where taken with a very cheap DMM so i know that are not accurate. If the sound is weird i will replace them with mkp1837 caps as per guide. The smd resistors are TNPW and r13 is Royalohm 1% 2w MF 50ppm. Output cap is JB JFX which are a pleasant surprise considering the fact that they are really cheap. I tried these as coupling caps in my AD1865 dac, and they outperformed Mundorf white MCap, Solen and Κ73-16. So until i can afford Mundorf supreme these caps will suffice.
Hoping of listening to music this night and not debugging!
I will bet You will take the Amtrans resistor out.
I had no SPL difference, I judged the low bass to bass regarding feedback potential at high SPL to the TT. R1 & R14 VAR had the stronger more differentiated bass little part influence also but others like Welwyn could be more tube like less bold but "creamier" nice on Jazz material.
Anyway its a happy outcome we mainly talk tuning and parts, carts, TTs, speakers, at this early builds point. And not hum, buzz, hiss, burned regs, DC offsets, smoke.
Testament to it proved a non problematic project to get started. Rest is the fun part of it that the builders will conclude individually and exchange tips. Quite a Christmas spirit project.
Testament to it proved a non problematic project to get started. Rest is the fun part of it that the builders will conclude individually and exchange tips. Quite a Christmas spirit project.
Sorry, I was talking to Analog_sa, about his bass balance. Maybe with what he compares with is not frequency balanced. Just maybe.
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No, the suggestion about SPL meter is not very useful. The 4 riaa circuits i compare have all been measured through an inverse riaa and proven to be accurate. They all get power from very similar dc sources. Some do not have coupling caps though.
Btw, just had a listen to the combo of a Sonicap Platinum .22/ Mundorf Sio 3.3 and in my system it is quite unlistenable. Replacing the teflon with a .22 Hovland brought in a very decent overall balance at a slight expense of transparency. This is obviously going to take a while
Btw, just had a listen to the combo of a Sonicap Platinum .22/ Mundorf Sio 3.3 and in my system it is quite unlistenable. Replacing the teflon with a .22 Hovland brought in a very decent overall balance at a slight expense of transparency. This is obviously going to take a while
If the teflon cap was not broken in, ie 400 hours of use, it will probably sound terrible at first. You may want to feed interstation noise from a tuner to it via inverse RIAA 7x24 for a few days. Just so long as it is selected on the linestage, or has a resistor across the output to gnd for a load, it will work.
Quite a Christmas spirit project.
Only regrets for not being in the camp. Not enough
Happy building and nice listening to everyone, nonetheless.
Only regrets for not being in the camp. Not enough
Best wishes to you too. Keep a board and 369s only and all rest can be obtainable in the future also.