That's very risky due to the headroom, there is actually implemented here but I think the output is probably 600mv.
AIDA LCR RIAA Tube Preamplifier – Nekolab
AIDA LCR RIAA Tube Preamplifier – Nekolab
I don't consider circuits without the test lab but only the listening session.
This is my point of view.
Personally each circuit I built , in proto or definitive, are tested on lab then listened in different configuration; in case some changes are needed, then misured again, then another listening session.
I have lot a friend ( and ex-customer) with different set up so it is easy for me to understand the way I have done.
And the phono stage is the worst circuit to play.
Mainly LCR type, of course.
Walter
This is my point of view.
Personally each circuit I built , in proto or definitive, are tested on lab then listened in different configuration; in case some changes are needed, then misured again, then another listening session.
I have lot a friend ( and ex-customer) with different set up so it is easy for me to understand the way I have done.
And the phono stage is the worst circuit to play.
Mainly LCR type, of course.
Walter
Finally I have completed the full dual LCR phono.
Double power trafo, double HT stabilized pcb ( dual channel each) so each stage of LCR is powered single.
Dual filaments power.
And a pcb for input with two arm selection and six selectable load
Walter
Double power trafo, double HT stabilized pcb ( dual channel each) so each stage of LCR is powered single.
Dual filaments power.
And a pcb for input with two arm selection and six selectable load
Walter
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Hi everyone, this is also to me a interesting question. Why not first start with two tube stages and implement the 600R LCR at the end? of course the second tube must be able to handle the higher signal gain.
A very expensive (and hyped) phonostage has one LCR filter between the two stages, but the second filter for the RIAA is at the end - after the second tube stage.
Any ideas, or experience?
@EuroChamp, Enzo is doing that, https://nekolab.it/2021/03/20/aida-lcr-riaa-preamplifier/
While I am not very confident for headrooms on second stage.
While I am not very confident for headrooms on second stage.
to 2A3set
The Aida is a LCR with CCS with sand so is not proper a tube circuit.
In addition the coils on LCR network are done from a general brand so if the value as L is good the Rdc must be checked.
This because the perfect frquency response comes also from this parameter.
In my case I have all the specs from Tango so the Sowter and new ones coils are compliant with the original.
About headroom I am agree
Last, no test report just to understand haow good is vthe final result
Walter
The Aida is a LCR with CCS with sand so is not proper a tube circuit.
In addition the coils on LCR network are done from a general brand so if the value as L is good the Rdc must be checked.
This because the perfect frquency response comes also from this parameter.
In my case I have all the specs from Tango so the Sowter and new ones coils are compliant with the original.
About headroom I am agree
Last, no test report just to understand haow good is vthe final result
Walter
CCS to me is a different topic.
1. ) My question was only related to where to place the LCR coil(s) - before or after the second tube. I understand, headroom can be a disadvantage. What are the advantages when doing so, if there are any?
2.) My idea is to use interstages in every stage. (LL1692A(am) or HL-10K-6)
A second option is to use anode chokes and in parafeed configuration add the interstages, where capacitors filter the DC. Interstages would not need air-gaps - because there is no DC. https://www.tubecad.com/2014/09/blog0308.htm
Parafeed is more expensive of course, but does it sound better?
Bernhard
1. ) My question was only related to where to place the LCR coil(s) - before or after the second tube. I understand, headroom can be a disadvantage. What are the advantages when doing so, if there are any?
2.) My idea is to use interstages in every stage. (LL1692A(am) or HL-10K-6)
A second option is to use anode chokes and in parafeed configuration add the interstages, where capacitors filter the DC. Interstages would not need air-gaps - because there is no DC. https://www.tubecad.com/2014/09/blog0308.htm
Parafeed is more expensive of course, but does it sound better?
Bernhard
It's pretty hard to calculate correct R/C value for diy lcr600 module (need very low DCR or a bit higher inductance for compensation?)
https://www.diyaudio.com/community/threads/riaa-lcr-mythos.227736/page-2#post-3505921
https://www.diyaudio.com/community/threads/riaa-lcr-mythos.227736/page-2#post-3505921