You mean voltages between ground and T7, T8 test points on the pcb ?
We can change this voltage with two 10K trimmers.
....or You mean something else...jfet's Idss are 6.45mA ?
We can change this voltage with two 10K trimmers.
....or You mean something else...jfet's Idss are 6.45mA ?
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Perhaps it is the 10uf Nichicon Gold electrolytic capacitors in the signal path. I think they may be adding a "brilliance" to the upper midrange that isn't unappealing but it is an addition. I am looking for alternatives that are compact and don't cost 1/2 the price of the whole kit.
Cheers
I mean the voltages T7 and T8 and ground. Never measured as I bought a set of jfets and resistors.
The trimmers do not adjust the 24V DC voltage but the bias for the tubes. Here is where it is on the schematic of one channel.
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Great! Now just do step by step test musurements of DC voltages from points T1 to T8 like in Mr.Pass article. Source : http://www.firstwatt.com/pdf/art_diy_nutube_preamp.pdf
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Oh my god how could I be so foolish. I thought those pots where for distortion regulation and I have placed a stereo pot on the front. I have adjusted to. 9.5 v now. I played around with that pots in our hifi club in Copenhagen. To bright sounding in all positions. There was only little differences.
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Yes is for distortion with his phase at specific voltage 🙂
This trimmers is easy to play for precise desired voltage
https://www.mouser.fr/ProductDetail...=sGAEpiMZZMvygUB3GLcD7lv7xXtevcsqvK8peaGZgso=
9.5V sound is on the wet side H2
12.5V is on the dry or bright side H3
With reversed power amplifier speakers polaritys I can hear another difference.
If this do not bring audio satisfaction then is possible
from "bright" CD player or DAC,
"brigh" power amplifier or
speakers + "bright" room acoustic
This trimmers is easy to play for precise desired voltage
https://www.mouser.fr/ProductDetail...=sGAEpiMZZMvygUB3GLcD7lv7xXtevcsqvK8peaGZgso=
9.5V sound is on the wet side H2
12.5V is on the dry or bright side H3
With reversed power amplifier speakers polaritys I can hear another difference.
If this do not bring audio satisfaction then is possible
from "bright" CD player or DAC,
"brigh" power amplifier or
speakers + "bright" room acoustic
to Erlend #4266
Hello Erlend,
I would say it is the most important possibility to play with the voltage at
T7/8 in the B1-NUTUBE-preamp.
Adjusting positive - negative 2nd- harmonic (adjustment over the 10Kohm trimpots) as well as to try to reverse the speaker-polarity.
The differences are subtle but for me clearly audible.
Test it! And have fun....😉
Greets
Dirk
Hello Erlend,
I would say it is the most important possibility to play with the voltage at
T7/8 in the B1-NUTUBE-preamp.
Adjusting positive - negative 2nd- harmonic (adjustment over the 10Kohm trimpots) as well as to try to reverse the speaker-polarity.
The differences are subtle but for me clearly audible.
Test it! And have fun....😉
Greets
Dirk
Allowd me... even if BG are wonderful, (wich they are), I would use PPPs. Without a doubt.
with triode , there are so many resistors that they're all practically in signal path
and here we have two more additional ones , so obviously in signal path
what's there not to understand ?
as Soundhappy did show , as result of his own time invested in Audiophoolery game ( and we all have our time invested in same game) - he found that even when there is difference , usual "Audio Superior" parts rarely bring difference in accord with difference in price
this Forum is all about brain and fun - how to have most fun with most brain and least money involved ........ in most cases not because something is super expensive and one can't afford it , but for brain sake
Now that I have all my order ready and so many new informations, I still have a dilema with boutique parts. Lytics. I know the difference between them and those Kaisei from Audio Note use to give me wonderful results in psu.
In your opinion, dear members, is it worth to use your favorite boutique lytics in this board?
In your opinion, dear members, is it worth to use your favorite boutique lytics in this board?
