Author Topic: My Tube Journey (Read 210317 times)

tony · « **Reply #690 on:** Apr 11, 2016 at 12:24 PM »

Quote from: ajayxyz11 on Apr 11, 2016 at 09:44 AM

Sir Tony I understand what you mean. Let's go back to the nice 5k preamp, say what if we make a better or special version of it with better parts, mundorfed, premium caps, etc..how much do you think are we looking on this? Also, is a balanced XLR output possible to add in a tube preamp? I've never seen one but wondering because my power amp also have inputs for balance connection. I beginning to get excited on this sir.

of course, what you wish for can be done....
XLR output on a true balanced output preamp is in the works..
i have been toying with this idea for a time now.....
but it will go far away from the original theme, a low cost amp that is bang for the back....
i have several other preamps, they cost more to make, but there are those who come back to me looking for those...
i made these preamps several years ago....

tony · « **Reply #691 on:** Apr 11, 2016 at 12:27 PM »

Quote from: rochie on Apr 11, 2016 at 10:07 AM

1 mundorf capacitor = 5k preamp

i tell those who want these in their amp to buy those themselves and i will gladly put them in,
if there is space for it...

otherwise i go by technology, polypropylenes are best for me, WIMA's are excellent caps...

rochie · « **Reply #692 on:** Apr 11, 2016 at 12:36 PM »

speaking of wima,this is from Danny E. designer of dny40w. this what he used on their workplace i guess.

tony · « **Reply #693 on:** Apr 11, 2016 at 12:39 PM »

those are golden treasures you got there rochie, are those for sale?

rochie · « **Reply #694 on:** Apr 11, 2016 at 12:52 PM »

Quote from: tony on Apr 11, 2016 at 12:39 PM

those are golden treasures you got there rochie, are those for sale?

you need some?ill send you the list.

tony · « **Reply #695 on:** Apr 11, 2016 at 12:53 PM »

thanks, please do....

ajayxyz11 · « **Reply #696 on:** Apr 11, 2016 at 01:01 PM »

Quote from: tony on Apr 11, 2016 at 12:24 PM

of course, what you wish for can be done....
XLR output on a true balanced output preamp is in the works..
i have been toying with this idea for a time now.....
but it will go far away from the original theme, a low cost amp that is bang for the back....
i have several other preamps, they cost more to make, but there are those who come back to me looking for those...
i made these preamps several years ago....

Glad to know about the balance connection sir Tony. Let's forget about the mondorf & go by the technology as you put in your quality amps. I agree with you on the WIMA's. Incorporating the XLR balance & using WIMA's to the 5k preamp design, how far are we adding in the budget cost sir? Can you quote me on this sir? I really am looking forward on this preamp. Thank you for entertaining me on my questions sir.

tony · « **Reply #697 on:** Apr 11, 2016 at 01:04 PM »

^ i have just the design you are asking for....
are you a fan of directly heated tubes like to 26 or 10y?
or indirectly heated types like the 6dj8 and 12au7's?

ajayxyz11 · « **Reply #698 on:** Apr 11, 2016 at 01:33 PM »

Quote from: tony on Apr 11, 2016 at 01:04 PM

^ i have just the design you are asking for....
are you a fan of directly heated tubes like to 26 or 10y?
or indirectly heated types like the 6dj8 and 12au7's?

Sir Tony, honestly Im a newbie in tube technology & to consider a direct or indirect heated tube, what's their advantage, disadvantage and how do I recognize one? I do like to learn this as part of my journey in this hobby. I appreciate some points but not too technical that I may not be able to understand yet.

ajayxyz11 · « **Reply #699 on:** Apr 11, 2016 at 03:30 PM »

Sir Tony, in short I am not really technically inclined & this would be my 1st tube preamp if you will help me own one. Which tube is more appropriate or best suited for this design? Thanks.

fishda · « **Reply #700 on:** Apr 11, 2016 at 05:32 PM »

I'm sure this project is going to be good.

tony · « **Reply #701 on:** Apr 11, 2016 at 07:26 PM »

Quote from: ajayxyz11 on Apr 11, 2016 at 03:30 PM

Sir Tony, in short I am not really technically inclined & this would be my 1st tube preamp if you will help me own one. Which tube is more appropriate or best suited for this design? Thanks.

okey, it will help if you can tell me the model number
of the power amp you are pairing this preamp with.
i need to consider the info on my design...
please pm me a budget that i can work around with....
i assure you the money spent will be well worth the finished product...
or you don't pay if not satisfied....
i am also looking to build balanced tube preamp for another project...

tony · « **Reply #702 on:** Apr 11, 2016 at 07:50 PM »

VTL Stereo 50, unit was wired for 110 volts but inadvertently plugged ot 220...
one of the 4 big caps shorted out, so i rewired the unit to run off the 220 volts
mains without the need to rewind the power traffos...
modified the power inlet to use the IEC socket for the power cable...

before

after...

NMM1 · « **Reply #703 on:** Apr 12, 2016 at 10:30 AM »

bookmarking.....

choyb · « **Reply #704 on:** Apr 12, 2016 at 10:35 AM »

Quote from: ajayxyz11 on Apr 11, 2016 at 03:30 PM

Sir Tony, in short I am not really technically inclined & this would be my 1st tube preamp if you will help me own one. Which tube is more appropriate or best suited for this design? Thanks.

Go for it, @ajayxyz11!
Hope Sir Tony can do a regular update-post of the build as he had done with his other projects!

Exciting!

tony · « **Reply #705 on:** Apr 12, 2016 at 11:46 AM »

yes, i have several chassis made and that will be in the works...for sure...

ajayxyz11 · « **Reply #706 on:** Apr 12, 2016 at 12:56 PM »

Quote from: tony on Apr 11, 2016 at 07:26 PM

okey, it will help if you can tell me the model number
of the power amp you are pairing this preamp with.
i need to consider the info on my design...
please pm me a budget that i can work around with....
i assure you the money spent will be well worth the finished product...
or you don't pay if not satisfied....
i am also looking to build balanced tube preamp for another project...

Hi Sir Tony, sent you PM po for power amp specs & budget. Pa-advise na lang po sa budget.

What is a good sounding tube that can be used? 12ax7 lang po usually naririnig ko from my friends amp. I think I'll just leave it to your personal discretion on what to use?

Thank you,
Jay Villanueva

tony · « **Reply #707 on:** Apr 12, 2016 at 07:47 PM »

Jay, pm replied....line preamps do not need to use the 12ax7 with today's program sources,
i have a tube line amp with XLR outputs that a friend brought in for tweaking...
once done i will seek his permission to lend to you, i am sure he wouldn't mind...
i am also coming up with a marantz clone due to insistent public demand...
i myself is amazed at why people find this line to their liking even though
this amp uses global negative feedback that most audiophiles abhor...

6dj8 line amp with xlr output jacks...

ajayxyz11 · « **Reply #708 on:** Apr 13, 2016 at 10:54 AM »

Quote from: tony on Apr 12, 2016 at 07:47 PM

Jay, pm replied....line preamps do not need to use the 12ax7 with today's program sources,
i have a tube line amp with XLR outputs that a friend brought in for tweaking...
once done i will seek his permission to lend to you, i am sure he wouldn't mind...
i am also coming up with a marantz clone due to insistent public demand...
i myself is amazed at why people find this line to their liking even though
this amp uses global negative feedback that most audiophiles abhor...

Sir 12ax7 is not my preference, I am leaving it you on what's more appropriate & better for the design, I'm sure they'lle be excellent for the works. Thanks!

tony · « **Reply #709 on:** Apr 13, 2016 at 01:53 PM »

Quote from: ajayxyz11 on Apr 13, 2016 at 10:54 AM

Sir 12ax7 is not my preference, I am leaving it you on what's more appropriate & better for the design, I'm sure they'lle be excellent for the works. Thanks!

great, then on to the design stage then...

tony · « **Reply #710 on:** Apr 14, 2016 at 09:56 AM »

i was able to track down the OEM of this line preamp, http://www.bezdz.com/engindex.html

although made in china, this amp uses american surplus caps, resistors and army surplus transformers...
of you look under the hood, you will find it parts laden...the price seems to come close to the cost of of parts...

picture does not give justice to the beauty of workmanship, i am awed.....
transformer coupled output for a balanced input just as i suspected....
i can not in conscience tamper with this line amp....i am sure there will be someone
who will find this amp to his liking...

i have converted this line amp to 220 volts, apparently there is a voltage selector at the back,
i merely covered it with black plastic strip after setting to 330 volts mains do that we do not have
to worry about Murphy....

dana · « **Reply #711 on:** Apr 14, 2016 at 11:24 AM »

nicely constructed.
volume step attenuator ba gamit nya papaT ?

tony · « **Reply #712 on:** Apr 14, 2016 at 11:29 AM »

yup, stepped attenuator.....

ajayxyz11 · « **Reply #713 on:** Apr 15, 2016 at 09:40 AM »

Ang ganda nyan sir, similar ba sa design nito gagawin mo for me sir?

tony · « **Reply #714 on:** Apr 15, 2016 at 12:27 PM »

Quote from: ajayxyz11 on Apr 15, 2016 at 09:40 AM

Ang ganda nyan sir, similar ba sa design nito gagawin mo for me sir?

much simpler, based on the Impasse preamp designed by my co-moderator at Diyaudio, Stuart Yaniger...http://www.tech-diy.com/Preamplifiers/ImPASSe/Impasse_LowRez.pdf

i am asking for permission from the owner to let you get a taste of this fine line amp.....please stand by...

btw, are you by any chance related to Danny Villanueva, i have been exchanging emails with him too..

tony · « **Reply #715 on:** Apr 16, 2016 at 08:13 AM »

@ajayxyz11, sent you pm...

tony · « **Reply #716 on:** Apr 16, 2016 at 08:55 AM »

after conversion to 220 volts, and replacement of 4(four) main filter caps of the same value,
it now time to calibrate this amp, steady idling B+ is at 500 vdc, first time for me to see
this on a 5881 tube.....but no signs of red plating, this amp is good to go...
bias seems close to each other....for final adjustment of bias, i set the grid voltage \
so that there is about 30mA on each cathodes for a tube dissipation of about 15 watts each
ensuring long tube life...
the original tube data shows 20 watts plate dissipation, new production claims 30, so i will rather be safe than sorry.....http://www.drtube.com/datasheets/5881-tungsol1962.pdf

tony · « **Reply #717 on:** Apr 16, 2016 at 09:33 AM »

another voltage conversion job done....Precision Fidelity locally modified psu...
power transformer rewind and busted/leaky caps replaced...
the owner gave me 2 (two) hitachi 6SN7's in another cashless transaction....
and i am going to make me a line stage out of it...
pm me if you want some and i will direct you to George, he says he has a lot more pairs left...

btw, this Precision Fidelity line amp is another clone of the much revered Marantz 7, and used the 12AX7...

ajayxyz11 · « **Reply #718 on:** Apr 16, 2016 at 02:34 PM »

Quote from: tony on Apr 15, 2016 at 12:27 PM

much simpler, based on the Impasse preamp designed by my co-moderator at Diyaudio, Stuart Yaniger...http://www.tech-diy.com/Preamplifiers/ImPASSe/Impasse_LowRez.pdf

i am asking for permission from the owner to let you get a taste of this fine line amp.....please stand by...

btw, are you by any chance related to Danny Villanueva, i have been exchanging emails with him too..

Sir Tony, though i cant understand a lot of technical terms, Impasse preamp seem very good, simple yet it has the efficiency to equal or better a more complex design. Really excited to see how you will build this one sir.
Sir Tony im not sure about sir Danny Villanueva po, maybe a distant relative if he's an ilocano hehe..

tony · « **Reply #719 on:** Apr 16, 2016 at 05:21 PM »

Quote from: ajayxyz11 on Apr 16, 2016 at 02:34 PM

Sir Tony, though i cant understand a lot of technical terms, Impasse preamp seem very good, simple yet it has the efficiency to equal or better a more complex design. Really excited to see how you will build this one sir.
Sir Tony im not sure about sir Danny Villanueva po, maybe a distant relative if he's an ilocano hehe..

i will ask him when i have the chance....i am building Nelson Pass Amp Camp, a mosfet single ended class A amp, i will need a balanced preamp to drive them also.....

the Impasse Preamp is a well engineered amp, pure science, no bell and whistles, no botique parts,
just pure sounds...