In my opinion...
...this 'drift' in the RIAA caps...
...is not dissimilar to hooking up a very low frequency LFO ( like in a guitar 'phaser' stomp-box eg. )
Which COULD be varying the response on a long ( several seconds ) cycle of up to 3%.
I figure, without 'rattling on' too much technical BS...
...this, in an 'inverse RIAA' for example ( smaller value caps )...
...could be about equal to roughly 0.25dB 'cycling drift' at the capacitors 'frequency points'.
( less either side, of course )
Mica seems the only way forward to me.
Cheers.
Si.
Also on inverse RIAA.
Get a wire-wound for the 500,000 Ohm & 40,000 Ohm resistor, if nothing else.
Phew !!!
...this 'drift' in the RIAA caps...
...is not dissimilar to hooking up a very low frequency LFO ( like in a guitar 'phaser' stomp-box eg. )
Which COULD be varying the response on a long ( several seconds ) cycle of up to 3%.
I figure, without 'rattling on' too much technical BS...
...this, in an 'inverse RIAA' for example ( smaller value caps )...
...could be about equal to roughly 0.25dB 'cycling drift' at the capacitors 'frequency points'.
( less either side, of course )
Mica seems the only way forward to me.
Cheers.
Si.
Also on inverse RIAA.
Get a wire-wound for the 500,000 Ohm & 40,000 Ohm resistor, if nothing else.
Phew !!!
I do not trust the seller´s measurements, that is why I measure all caps myself using a calibrated measurement.
That is my opinion also.
That is how I do it also.
Your LCR is calibrated?
If it's calibrated more than 1 year ago needs re-calibrating?
Your LCR have 4 wires Kelvin connection?
How many time do you have the 0.3% capacitors & the 0.1% resistors?
If your need absolute values the only right way is to buy a precision LCR with 4 wires Kelvin connection & calibrated by a Lab, if not the rest of your measurements aren't valids
Merlin
I believe we are heading to an endless discussion... Anyway, I relatively trust my measurement methodology. Whenever I read a 0.3% cap or a 1% cap, the values I find are coincident.
In the end, what matters more is the relative matching between channels and that can be obtained with regular equipment.
I have listened to numerous riaa amps, some built with great discrepancies regarding Lipshitz calc, and they sound good so....
I believe we are heading to an endless discussion... Anyway, I relatively trust my measurement methodology. Whenever I read a 0.3% cap or a 1% cap, the values I find are coincident.
In the end, what matters more is the relative matching between channels and that can be obtained with regular equipment.
I have listened to numerous riaa amps, some built with great discrepancies regarding Lipshitz calc, and they sound good so....
Totally agree... we can never be sure, even the 1% caps we buy can have less than perfect values.
Strangely the caps you sent me measured exactly the same with my meter.
The ones that Michael sends me are also spot on, and the ones I got from Peter (Acoustic Dimension) also have really close values to those I measure here, so I guess we are not far from the truth.
The important thing it's enjoy doing DIY.
Possible our two LCR have the same unaccuracy.
I don't know how measures Michael Percy: never asked him but seriously I doubt he have a Lab precision calibrated LCR.
P.S. we can match with a bad LCR but we can't measure well with a bad LCR....
Possible our two LCR have the same unaccuracy.
I don't know how measures Michael Percy: never asked him but seriously I doubt he have a Lab precision calibrated LCR.
P.S. we can match with a bad LCR but we can't measure well with a bad LCR....
Last edited:
Hi Ricardo
I saw your earlier post on the wire-wounds.
INDUCTANCE.
-----------------
I too was concerned about this.
But aparently this is pretty much a 'non issue', especialy compared to 'capacitor drift'.
Morgan Jones's in his book 'Valve Amplifiers' says something like...
...the inductance even of small R's ( potentialy the worst ) is all but 'insignificant' for our purposes.
Worst case, 0.5deg phase-shift @ 100Khz ( low value R ).
Manufacturers old & new, are all winding to avoid inductance anyhow.
EXPENSE.
-----------
Well...
...Yes, they are a bit expensive.
But, how much does a 'teeny-weeny' 'audiophool' resistor cost ?
I've bought a few; as much, if not alot more than a wire-wound.
How many resistors are in a 'Simplistic' anyhow ?...not many.
How many quality wire-wounds can you buy for the price of 1 'gold-plated cap' ?...
A lot.
SIZE.
-----
Yep...'size doesn't matter' ?...
...Well it does, if you're trying to 'stuff' a tiny kit PCB with them...
...problems...problems...problems...
I guess that's another reason people save 'em for valve stuff.
However, every 'Simplistic' is like the best 'prototype racing car'...
...every one, uniquely different ( but similar ), all built for MAXIMUM performance.
( That's why I like this thread ! )
So.
Why not ?
Still finding parts here...
...but we start soldering in a few more weeks, I rec.
Pictures of course, in due time.
Cheers.
Si.
Now...
...if I put the pre-amp in a vat of liquid nitrogen ( like the radio-telescope guys 'listening to outer-space do ), could I get the performance even better.
This, I'm afraid to say, is how we are thinking at 'Space Egg' on this one.
Made some 'clips', with a couple of pF's on !!!!!!!!!!!!
Nice !
I saw your earlier post on the wire-wounds.
INDUCTANCE.
-----------------
I too was concerned about this.
But aparently this is pretty much a 'non issue', especialy compared to 'capacitor drift'.
Morgan Jones's in his book 'Valve Amplifiers' says something like...
...the inductance even of small R's ( potentialy the worst ) is all but 'insignificant' for our purposes.
Worst case, 0.5deg phase-shift @ 100Khz ( low value R ).
Manufacturers old & new, are all winding to avoid inductance anyhow.
EXPENSE.
-----------
Well...
...Yes, they are a bit expensive.
But, how much does a 'teeny-weeny' 'audiophool' resistor cost ?
I've bought a few; as much, if not alot more than a wire-wound.
How many resistors are in a 'Simplistic' anyhow ?...not many.
How many quality wire-wounds can you buy for the price of 1 'gold-plated cap' ?...
A lot.
SIZE.
-----
Yep...'size doesn't matter' ?...
...Well it does, if you're trying to 'stuff' a tiny kit PCB with them...
...problems...problems...problems...
I guess that's another reason people save 'em for valve stuff.
However, every 'Simplistic' is like the best 'prototype racing car'...
...every one, uniquely different ( but similar ), all built for MAXIMUM performance.
( That's why I like this thread ! )
So.
Why not ?
Still finding parts here...
...but we start soldering in a few more weeks, I rec.
Pictures of course, in due time.
Cheers.
Si.
Now...
...if I put the pre-amp in a vat of liquid nitrogen ( like the radio-telescope guys 'listening to outer-space do ), could I get the performance even better.
This, I'm afraid to say, is how we are thinking at 'Space Egg' on this one.
Made some 'clips', with a couple of pF's on !!!!!!!!!!!!
Nice !
Really true.The important thing it's enjoy doing DIY.
Possible our two LCR have the same unaccuracy.
I don't know how measures Michael Percy: never asked him but seriously I doubt he have a Lab precision calibrated LCR.
P.S. we can match with a bad LCR but we can't measure well with a bad LCR....
I enjoy DIY a lot... now I have a seriously sounding system without the burden of the brand and cost
Hi Ricardo
I have hundreds of wire-wounds in that range.
They are mostly made by either Welwyn or ERG.
500,000 Ohms is difficult to find...
...I have some on order from Japan at the moment.
1,000,000 Ohms is also difficult to find...
...but I have some coming from Tulsa USA any day now.
Cheers.
Si.
I have hundreds of wire-wounds in that range.
They are mostly made by either Welwyn or ERG.
500,000 Ohms is difficult to find...
...I have some on order from Japan at the moment.
1,000,000 Ohms is also difficult to find...
...but I have some coming from Tulsa USA any day now.
Cheers.
Si.
News bulletin.
I look forward to your impressions. I have the TSSA waiting and the your RIAA is on the bench in planning stages.
Hi again Ricardo
By the way; don't get me wrong on the Polystyrene caps.
The last 2 phono-pre's I made had these, as people do; and sounded groovy !
I just post-up what's on my mind at the time & hope to see what other people think, or have done with the same problem.
I'm also I think, the last person in the world to have discovered eBay !
When I built the last 2 phono-pre's ( years ago ), I probably didn't even consider using Silver-Mica ( far TOO expensive maybe ).
5 mins on eBay now though, & you've got your self a 'bucket full' of top-quality USSR capacitors for 'pocket-money' prices.
I figure the Russian capacitors look to me like the best made available !
I bought Teflon 15nF & 47nF for my EQ, and will certainly try them out ( & Polystyrene as well ).
Some guy posted earlier that he was 'saving up' for some capacitors.
I mean, if I had to eat brown-rice over Christmas to afford a couple of little 'plastic blocks'...
...I would worry that I might just be missing the point entirely.
Which to me ( and you ), is simply about 'listening' to what sounds good.
No 'high-end' pretensions here at Space Egg...
...like you say " good sounding, no brand, affordable system "...
...perfect !
Learnt years ago, it aint about how much money you spend...
...it's about how much time you put in listening & working on 'your sound' !
BOO JAH !
" Aint that the truth "
Cheers
Si.
P.S. The men in 'the white coats' are coming for me & my wire-wounds !
I'm in the WW asylum for sure !
By the way; don't get me wrong on the Polystyrene caps.
The last 2 phono-pre's I made had these, as people do; and sounded groovy !
I just post-up what's on my mind at the time & hope to see what other people think, or have done with the same problem.
I'm also I think, the last person in the world to have discovered eBay !
When I built the last 2 phono-pre's ( years ago ), I probably didn't even consider using Silver-Mica ( far TOO expensive maybe ).
5 mins on eBay now though, & you've got your self a 'bucket full' of top-quality USSR capacitors for 'pocket-money' prices.
I figure the Russian capacitors look to me like the best made available !
I bought Teflon 15nF & 47nF for my EQ, and will certainly try them out ( & Polystyrene as well ).
Some guy posted earlier that he was 'saving up' for some capacitors.
I mean, if I had to eat brown-rice over Christmas to afford a couple of little 'plastic blocks'...
...I would worry that I might just be missing the point entirely.
Which to me ( and you ), is simply about 'listening' to what sounds good.
No 'high-end' pretensions here at Space Egg...
...like you say " good sounding, no brand, affordable system "...
...perfect !
Learnt years ago, it aint about how much money you spend...
...it's about how much time you put in listening & working on 'your sound' !
BOO JAH !
" Aint that the truth "
Cheers
Si.
P.S. The men in 'the white coats' are coming for me & my wire-wounds !
I'm in the WW asylum for sure !
Hi Ricardo
Phew !!!
Men in white coats...
...not come today !!!
But more wire-wounds from eBay did !!!
2 Questions Ricardo.
I have the K72 Teflons...100n 47n 15n
I think...max value available...not enough for output cap.
But I see FT3 as well...higher values I think.
( I will look again today )
What do you like/use FT3 for ?
Any different to K72 ?
Or just different packaging ?
&
What resistors in your 'Wallace Experiment' are the ones you speak of being 'most important'.
Series...Yes.
Source resistors ?
Is that why you asked about 'low value' WW's ?
Cheers.
Si.
I did save 'The Wallace Experiment' schematic, so I have the R position #'s.
Phew !!!
Men in white coats...
...not come today !!!
But more wire-wounds from eBay did !!!
2 Questions Ricardo.
I have the K72 Teflons...100n 47n 15n
I think...max value available...not enough for output cap.
But I see FT3 as well...higher values I think.
( I will look again today )
What do you like/use FT3 for ?
Any different to K72 ?
Or just different packaging ?
&
What resistors in your 'Wallace Experiment' are the ones you speak of being 'most important'.
Series...Yes.
Source resistors ?
Is that why you asked about 'low value' WW's ?
Cheers.
Si.
I did save 'The Wallace Experiment' schematic, so I have the R position #'s.
News bulletin.
Regards for George, one lucky bastard
Hi Si
Ft3 teflon 100n for interstage cap much better than K72... really see throu imagery... the best.
Low value WW: 2ohm, 3ohm, .... 47ohm for Rs (noise generators) in the input stage