A recent statement from Scott Wurcer!
Quote : Honestly, build Salas' Simplistic RIAA if you can HONESTLY tell it over a Blowtorch then get out your snowblower.
Quote : Honestly, build Salas' Simplistic RIAA if you can HONESTLY tell it over a Blowtorch then get out your snowblower.
Thanks for the info. Why 300mA? We need a version as first shunt regulator / pre regulator which handles all the current like before.
Next use 3 shunt regs for each stage and share it for left & right channel. The shunts should be as near as possible to the amplifier.
Correct and I agree.
Ricardo,
you know what I mean? Here again:
- use a preregulator in the power supply chassis
- use 3 regs in the amplifier chassis
- share the 1st reg for the 1st amplifier stages (connect the B+ from the left and right channel)
- same with the other regs for the 2nd & 3rd stage
A happy new year to all forum members here 🙂
Hi João
I experimented using the same shunt for both right and left channels and also one shunt per channel.
The latter produces much more separation and detail.
Using two independent psu´s, further increases this effect.
Why not use 4 shunts instead of 3 .... feed both 1st stages individually and 2nd stages individually.
Why the need to feed the buffer individually ?
I experimented using the same shunt for both right and left channels and also one shunt per channel.
The latter produces much more separation and detail.
Using two independent psu´s, further increases this effect.
Why not use 4 shunts instead of 3 .... feed both 1st stages individually and 2nd stages individually.
Why the need to feed the buffer individually ?
Just finished implementing the Lundahl SUT on one 48dB Riaa and the results are quite good.
No hum and the sound does not get too fat even with a 0.8mv cart... hope it works allright with the target (A special 0.15mV cart).
Strangely, I notice that the SUT amplifies the signal but also amplifies the noise floor, so the usual hiss I hear at full volume (without input signal) is also amplified.
No hum and the sound does not get too fat even with a 0.8mv cart... hope it works allright with the target (A special 0.15mV cart).
Strangely, I notice that the SUT amplifies the signal but also amplifies the noise floor, so the usual hiss I hear at full volume (without input signal) is also amplified.
Ricardo, you can try different placement and or shielding of the SUT. These things pick up noise easilly. I know it's best to be as close as possible to the RCA's. If you post a picture, maybe someone can help you more.
Ricardo you load the primary or sec ? there is a lot bla-bla on this ...search on AA
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Hi vgeorge
I am sure ir is not picking up noise.... There is absolutely no hum.
The noise I am talking about is the normal riaa noise floor. It gets amplifyed along with the cart signal.
I am sure ir is not picking up noise.... There is absolutely no hum.
The noise I am talking about is the normal riaa noise floor. It gets amplifyed along with the cart signal.
I am loading the secondary with 47k.
I left room for loading the primary if I need to go lower than the resulting 470ohm (1:10)
Scott Wurcer is one of the most clever engineers on the planet. He is cleverly humorous too, don't underestimate that. Keep this thread as it started, claim free.
AA is everywhere around the US.
We could all use a 12 step problem of some sort.
I don't get the snowblower analogy, although we use them of course this time of year.
We could all use a 12 step problem of some sort.
I don't get the snowblower analogy, although we use them of course this time of year.
It's accepted that the mosfet CCS works best over 200 mA. 3 complete shunt regs will draw over 600 mA. Ad I do mind the polar bear 😉, I arbitrarily halved that value.
Feliz ano novo 2U too!
Ok that describes my experience as well. But the version I described makes you dance and enjoy more listening to the music. It makes better inner dynamics and rythm. Try it out.
BTW, we don't have true different mono signals as L+R channel. Mastering means to use pan pots (panorama pots) to place the groups or instruments. Think about this point.
Mono power supplies male sence in mono power amps to get smaller power supplies.
Good point, but I'd recommend the opposite and feeding the output stages individually!
Make it stable and inependet for load problems, here cables to the line stage. And if you're using a passive pre, in form of a TVC, then you can drive it easily.
Um feliz ano novo. Amor, saude e dinheiro!