Hi salas
I forgot to tell you this is the underside of the board.
Apart from that issue, do you agree with the overall schematic ?
I forgot to tell you this is the underside of the board.
Apart from that issue, do you agree with the overall schematic ?
Yes it looks OK. I would make provision for an alternative general earthing point to star at C2 earth node too, just in case. Also try a 1k8 R20 on your current phono to see if it stabilizes easier.
Thank you Salas
Increasing R20 lowers voltage in Q5.... will it affect sound quality ?
What should I expect ?
Should I have more than 1 GND point ? my actual setup has one star gnd where all gnd´s go.
Increasing R20 lowers voltage in Q5.... will it affect sound quality ?
What should I expect ?
Should I have more than 1 GND point ? my actual setup has one star gnd where all gnd´s go.
I meant to have one point still, but different take off alternatives just in case. Regarding R20 I thought it may help you if there is less voltage across Q5 regarding the noises you get. Since nobody else ever got the noises, I don't know more. Its a proposed experiment. You will tell if it helps the noises you get during warm up or if it changes the sound. The current remains the same.
I believe noises come from bad solder joints... my pcb is now a real mess.... that is why I want to rebuild everything.
If nobody else reported any issues, maybe I should stick to your original design.
Another pertinent question:
I am now using 2K21 RC55Y Welwin 0,1% metal film for cart loading and really think this is the perfect value.
I would like to try Shinkoh in there but do not know if I need to change the value.
I would really apreciate your comment.
Ricardo
If nobody else reported any issues, maybe I should stick to your original design.
Another pertinent question:
I am now using 2K21 RC55Y Welwin 0,1% metal film for cart loading and really think this is the perfect value.
I would like to try Shinkoh in there but do not know if I need to change the value.
I would really apreciate your comment.
Ricardo
Normally Shinkoh gives the most grain free and organic rendering there. But not heavy at the same time. I would keep the value. Only thing is that with Shinkoh you can normally go higher in value before you get some ''pinch'' as with other resistors.
Can you please suggest a good quality DMM ?
Myne is able to read capacitances but I always get lower values than indicated in the caps. (For instance, K72-6 0.047u reads 44.6nF)
ERO 620pF reads 599pF....
Mundorf 4.7uF MKP reads 4.4u ...
😕
Myne is able to read capacitances but I always get lower values than indicated in the caps. (For instance, K72-6 0.047u reads 44.6nF)
ERO 620pF reads 599pF....
Mundorf 4.7uF MKP reads 4.4u ...
😕
You will not find accuracy in multimeters for capacitance unless you pay some rather serious money. See e-bay for second hand FLUKE.
Hi everybody,
just an update to my latest mods.
First I replaced the inductors with normal EI core 10H 200ma - as per Salas suggestion - and put first the 2200uF capacitor in my CLC filter.
There was some better refining of the sound, but nothing spectacular.
After that, I replaced the 47nF PIO in the RIAA with an Obligato premium, bypassed by a silver mica, in order to get 46,9nF.
This was a big improve of the sound!
Also not to forget, I moved the bypass capacitors closer to the positive leg.
Next, I am waiting for some 16nF russian silver mica, as well as some 47nF silver mica, in order to replace and compare.
Thanks everybody!
PS. Salas, tube project is going well!
just an update to my latest mods.
First I replaced the inductors with normal EI core 10H 200ma - as per Salas suggestion - and put first the 2200uF capacitor in my CLC filter.
There was some better refining of the sound, but nothing spectacular.
After that, I replaced the 47nF PIO in the RIAA with an Obligato premium, bypassed by a silver mica, in order to get 46,9nF.
This was a big improve of the sound!
Also not to forget, I moved the bypass capacitors closer to the positive leg.
Next, I am waiting for some 16nF russian silver mica, as well as some 47nF silver mica, in order to replace and compare.
Thanks everybody!
PS. Salas, tube project is going well!
Hi vgeorgevgeorge said:
This is exactly what i was waiting for. I am now very confident to replace the 47n PIO by a 47n obbligato.
What value is the obbligato ? (Why did you need to bypass ?)
Ricardo
Yes Salas the 12B4 pre. Everything is on the air now. Just missing a transistor for the HVshunt.
Rcruz, you will be shocked by the difference!
I measured the obligato and it was 46.5 both of them. I added a 450pF silver mica to get close to 47nF.
Rcruz, you will be shocked by the difference!
I measured the obligato and it was 46.5 both of them. I added a 450pF silver mica to get close to 47nF.
Just email me before you put the 12B4 together, so to tell you a few things about different options to try (Anode constant current, electronic choke, resistor) bcs some systems lend themselves better to one or the other, considering gain, speakers SPL, main amp's sensitivity etc.
Of course I remember! 1979. Catchy clean tempo.
Back in those days The Police did make great post Punk White Reggae. I would like to listen to Stewart Copeland again on a brand new vinyl copy of the 1979 Reggatta de Blanc, on a 100dB sens dipole midbass system with Constant Directivity horn mids and highs, and 5 subwoofers scattered in Geddes way.😉
Back in those days The Police did make great post Punk White Reggae. I would like to listen to Stewart Copeland again on a brand new vinyl copy of the 1979 Reggatta de Blanc, on a 100dB sens dipole midbass system with Constant Directivity horn mids and highs, and 5 subwoofers scattered in Geddes way.😉
