Hey JoshK,
I live on Long Island.
I would have loved to be present for that! I have a SS Rotel Michi amp that I would like to match up with a Tube Pre/Linestage, although I don't think it would qualify as a difficult one!
Is this just an Audio Club or is it with DIY as well?
Thanks!
Regards//Keith
I live on Long Island.
I would have loved to be present for that! I have a SS Rotel Michi amp that I would like to match up with a Tube Pre/Linestage, although I don't think it would qualify as a difficult one!
Is this just an Audio Club or is it with DIY as well?
Thanks!
Regards//Keith
pchw Thank you for your order
Thank You for your order and your business we really appreciate your purchase and your sharing with the community where you purchased the product. We are one of the largest vacuum tube suppliers in the country with over 3.5 million products stocked. Please check out http://www.thetubecenter.com to see if we can help any of you with your next DIY prjoject.
Thank You
The Tube Center Webmaster
http://www.thetubecenter.com
Thank You for your order and your business we really appreciate your purchase and your sharing with the community where you purchased the product. We are one of the largest vacuum tube suppliers in the country with over 3.5 million products stocked. Please check out http://www.thetubecenter.com to see if we can help any of you with your next DIY prjoject.
Thank You
The Tube Center Webmaster
http://www.thetubecenter.com
pchw that amp looks nice.
i have some 3way 84db speakers (ribbons too), how much power do you need to get some decent listening levels?
i'm thinking about building a tube power amp after i build phono and line stage preamps.
i gotta get my posts up, i wanted to send a pm to poindexter about the schematic he posted on page one but i can't since i'm under moderation still...
i have some 3way 84db speakers (ribbons too), how much power do you need to get some decent listening levels?
i'm thinking about building a tube power amp after i build phono and line stage preamps.
i gotta get my posts up, i wanted to send a pm to poindexter about the schematic he posted on page one but i can't since i'm under moderation still...
how much could someone build this/your preamp for?
http://www.audiotropic.net/Demo/littleMoeb.gif
i can pickup a foreplayIII kit for $220 shipped still needing to be put together...and i'm almost about to send the guy money but....i ran across this thread. lol.
it'll be my first journey into tube electronics and the ease and instructions of the bottlehead appeals to me a little...but if i can build somethng better than...you know...i'd like to.
http://www.audiotropic.net/Demo/littleMoeb.gif
i can pickup a foreplayIII kit for $220 shipped still needing to be put together...and i'm almost about to send the guy money but....i ran across this thread. lol.
it'll be my first journey into tube electronics and the ease and instructions of the bottlehead appeals to me a little...but if i can build somethng better than...you know...i'd like to.
Sorry about that, Akira, it's been a little busy out. The reason I asked about your B+ voltage is because I'm now using the 6T4 tube, a device I find noticeably superior due to its lack of microphonicity and partition noise. The kicker is that the 6T4 has a very restrictive Vh-k rating, 50V below the cathode and 25V (!) above, so if your B+ is over 150Vdc, you have to have two heater supplies referenced to different voltages; you can't stay within both ratings with a single supply, no matter where you reference it.
There are a lot of places to go wrong in PSUD, mostly in the effective DCR specs of the power transformer and choke. In your case, both these values are set at about 30Ω, which looks pretty low to me. The resistance of my power trans secondary is more like 70Ω, and the choke is on the order of 300Ω. DCR measurements are easy to take, so get to work!
:^)
Poinz
There are a lot of places to go wrong in PSUD, mostly in the effective DCR specs of the power transformer and choke. In your case, both these values are set at about 30Ω, which looks pretty low to me. The resistance of my power trans secondary is more like 70Ω, and the choke is on the order of 300Ω. DCR measurements are easy to take, so get to work!
:^)
Poinz
Hi guys, i am new to tubes and would like to build this linestage as it seems simple and its in my understanding to read the schematic.
But i have newbie questions, please bare with me.
1. referencing
http://tdsl.duncanamps.com/show.php?des=6T4
I use part of Poindexter's schematic posted in the beginning of the threat for smaller file, can someone help me confirming the pins are correctly identified?
as i try to match with akirasugai's post inside pic of the amp and it didnt match with the reference above. thx
2. i am wondering what the use of linking the heater tranformer ct to the B+?
quoting from Poindexter "Second, be sure that you reference the heater voltage to an elevation of 25v above ground, as I do, to observe the very restrictive heater-cathode voltage of the 6T4, which is 50v down or 25v up from the cathode (!)." is this the reason?
thanks in adv. happy listening
But i have newbie questions, please bare with me.
1. referencing
http://tdsl.duncanamps.com/show.php?des=6T4
I use part of Poindexter's schematic posted in the beginning of the threat for smaller file, can someone help me confirming the pins are correctly identified?
as i try to match with akirasugai's post inside pic of the amp and it didnt match with the reference above. thx
2. i am wondering what the use of linking the heater tranformer ct to the B+?
quoting from Poindexter "Second, be sure that you reference the heater voltage to an elevation of 25v above ground, as I do, to observe the very restrictive heater-cathode voltage of the 6T4, which is 50v down or 25v up from the cathode (!)." is this the reason?
thanks in adv. happy listening
Attachments
6AF4 looks nearly identical in its characteristics and heater requirements, but has substantially lower current and power dissipation ratings, you'd be on the edge of its current rating. It looks a plug in replacement, so you could try them. I picked up on the 6T4 because they're plentiful and cheap. If you have a couple of fave vendors, go to them and ask about availability and price of the 6T4 and 6AF4.
Aloha,
Poinz
Aloha,
Poinz
I'm pretty certain I only wired to one of the pins for the plate/grid - I must open her back up again and add a link across.
Does it make any difference sonically or electrically? I only ask because I have always measured the A to gnd and K to gnd as a couple of volts different on each channel (see link). I wonder if wiring to both pins would make that little bit of difference?
Great little preamp BTW....
Fran
Does it make any difference sonically or electrically? I only ask because I have always measured the A to gnd and K to gnd as a couple of volts different on each channel (see link). I wonder if wiring to both pins would make that little bit of difference?
Great little preamp BTW....
Fran
Well, it sure looks like it to me. The grid (on my RCAs, anyway) is wound on two posts, and one pin goes to each post. Maybe, maybe not. The plate, however, is in two pieces that are sort of 'U' shaped (with heat wings going off), and one pin goes to each side. If the two halves are connected in another place, I dunno.
Some tubes with doubled up pins I've looked at and the two pins are wired to the same place anyway, so who cares, but in this case it looked to me like a good idea to wire up both pins.
If you fix it, have a good listen first, and then see if you can hear any difference.
Aloha,
Poinz
Some tubes with doubled up pins I've looked at and the two pins are wired to the same place anyway, so who cares, but in this case it looked to me like a good idea to wire up both pins.
If you fix it, have a good listen first, and then see if you can hear any difference.
Aloha,
Poinz
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