Hi everyone, I have:
- a pair of 5K:8ohm Telefunken OPT's
-574V CT 1.26A (5V@4A, 6.3V@4.6A) Power transformer. (Magnavox salvage, if hooked up as original AMP142 schematics yields around 270DC.(2 x 5Y3, 1HY choke)
I have already built myself a PPP 6V6 stereao amp and I love it. Now I want to try my hand at a Single Ended build, see what all the fuss is about.
I'm not looking for crazy power, my other amp is pretty decent in that department. I don't really want a flea amp either. My understanding is that if I run a 6V6 or 6L6 in class A or triode or tetrode brings the power output down as compared to pentode mode.
I do have efficient speakers, and can play around with the ohms, if I need to reflect a change back to the amp (4,6,8 ohm etc) I can change or purchase speakers for it down the road, although it would be nice if I could have 8ohm taps.
I also notice the 6L6 requires around 280V in that scenario. I thought this might work well with my power transformer. Also notice it can use my 5K opt's
I worry if I run a single 6V6 SE and start playing around with tetrode or triode that it might be too shy on power, thus the 6L6 appeals to me.
I am trying to learn to use Duncans PSUD, aside from that I should be able to play with my voltage a bit. I have 5U4, 5Y3 or solid state diodes. (Also have less common rectifiers in my box.) Could even use a 6volt if needed.
What do you guys think 6V6 or 6L6? Looking for quality. I think the 6V6 might be the nicer sounding tube, maybe just to quiet- thus the 6L6 comes into play. I'm thinking I need around a 5w amp although I'm willing to try a little less for quality's sake.
Once I get that sorted out I have some small signal tubes here like: 6GH8,6SN7,6CG7,12**7, 6C4 etc.
AL
- a pair of 5K:8ohm Telefunken OPT's
-574V CT 1.26A (5V@4A, 6.3V@4.6A) Power transformer. (Magnavox salvage, if hooked up as original AMP142 schematics yields around 270DC.(2 x 5Y3, 1HY choke)
I have already built myself a PPP 6V6 stereao amp and I love it. Now I want to try my hand at a Single Ended build, see what all the fuss is about.
I'm not looking for crazy power, my other amp is pretty decent in that department. I don't really want a flea amp either. My understanding is that if I run a 6V6 or 6L6 in class A or triode or tetrode brings the power output down as compared to pentode mode.
I do have efficient speakers, and can play around with the ohms, if I need to reflect a change back to the amp (4,6,8 ohm etc) I can change or purchase speakers for it down the road, although it would be nice if I could have 8ohm taps.
I also notice the 6L6 requires around 280V in that scenario. I thought this might work well with my power transformer. Also notice it can use my 5K opt's
I worry if I run a single 6V6 SE and start playing around with tetrode or triode that it might be too shy on power, thus the 6L6 appeals to me.
I am trying to learn to use Duncans PSUD, aside from that I should be able to play with my voltage a bit. I have 5U4, 5Y3 or solid state diodes. (Also have less common rectifiers in my box.) Could even use a 6volt if needed.
What do you guys think 6V6 or 6L6? Looking for quality. I think the 6V6 might be the nicer sounding tube, maybe just to quiet- thus the 6L6 comes into play. I'm thinking I need around a 5w amp although I'm willing to try a little less for quality's sake.
Once I get that sorted out I have some small signal tubes here like: 6GH8,6SN7,6CG7,12**7, 6C4 etc.
AL
Maybe I asked a common question. I'm starting to get some good results with some deeper googling.
Something along the lines of RH807 or a Tubelab ish SE sound good?
Something along the lines of RH807 or a Tubelab ish SE sound good?
Don't assume that your OPT's, which in the other thread you state are intended for 6BQ5 etc., can handle the extra DC current needed to get power out of a 6L6 or 807. Test this with a non-permanent setup first. If you want to play conservative then go for the 6V6's.
OK thanks for the advice.
From the data sheets I see around 1.2 watts for class A triode SE connection. (6L6)
Do you think that setup would stress them too much?
My logic if it could handle a 6V6 at around 5w I should be OK with a low voltage 6L6.
I'm about 70/30 leaning towards the 6L6, just to build with a different tube and because I have a very beefy PT. Now I just remembered I have a PT from a 6V6 PP mono amp I may be able to use.
From the data sheets I see around 1.2 watts for class A triode SE connection. (6L6)
Do you think that setup would stress them too much?
My logic if it could handle a 6V6 at around 5w I should be OK with a low voltage 6L6.
I'm about 70/30 leaning towards the 6L6, just to build with a different tube and because I have a very beefy PT. Now I just remembered I have a PT from a 6V6 PP mono amp I may be able to use.
OK, well you're definately not getting the message, because if you bias the 6L6 for a lower plate voltage/higher cathode current operating point, you are making the situation worse and increasing the likelihood of OPT DC saturation. Maybe do a bit more reading up on the basics first.
......and here comes the thread brake.
Well as I said I have various power supply options, up to about 425V.
Let's just relax, I'm just eyeballing the datasheets to get a game plan.
From some of the reading I have done it seems doable, no need for panic.
Do you have and schematics for an amp based on my first post?
Well as I said I have various power supply options, up to about 425V.
Let's just relax, I'm just eyeballing the datasheets to get a game plan.
From some of the reading I have done it seems doable, no need for panic.
Do you have and schematics for an amp based on my first post?
+3 votes for 6V6 then.
Actually that's were I started. lol Full circle.
So would be looking at around 2 watts with the RH84 I think?
I suppose it's worth trying maybe a 6SN7/6V6 RH84 on a board and see how it sounds.
I strayed away from it just due to so many "needs very efficient speakers" and " a little bass shy" comments. I guess the only way to find out is to try it.
I do understand by the nature of SE it's bass shy vs. PP etc. Thought I might have been able to avoid that using the 6L6, and just go ahead and build the chassis etc. and tinker with it later.
Seems apparent I will have to try some stuff on a board first.
Maybe I'll start a thread on it. Thanks!
AL
Actually that's were I started. lol Full circle.
So would be looking at around 2 watts with the RH84 I think?
I suppose it's worth trying maybe a 6SN7/6V6 RH84 on a board and see how it sounds.
I strayed away from it just due to so many "needs very efficient speakers" and " a little bass shy" comments. I guess the only way to find out is to try it.
I do understand by the nature of SE it's bass shy vs. PP etc. Thought I might have been able to avoid that using the 6L6, and just go ahead and build the chassis etc. and tinker with it later.
Seems apparent I will have to try some stuff on a board first.
Maybe I'll start a thread on it. Thanks!
AL
If you want to stay octal, 6SL7 and 6V6. The SL will give a better characteristic for the plate to grid feedback scheme
It doesn't look like I have any of those.
It would be nice to stay octal, but I'm not that vein.
What else would be good for the signal tube, I have some NOS 6GH8,6SN7,6CG7,12A*7, 6C4 etc. I have lot's of other tube if you have any other suggestions, I might have it.
It would be nice to stay octal, but I'm not that vein.
What else would be good for the signal tube, I have some NOS 6GH8,6SN7,6CG7,12A*7, 6C4 etc. I have lot's of other tube if you have any other suggestions, I might have it.
I have a 6SN7 / 6V6 SE posted on this site.
I also have a 6SL7 /6V6 SE.
Advance search on my name and look at the schematics.
Both sound very good but will not knock down walls or anger the neighbors.
I may be totally out of the park but are your Telefunken OPT's SE types?
I also have a 6SL7 /6V6 SE.
Advance search on my name and look at the schematics.
Both sound very good but will not knock down walls or anger the neighbors.
I may be totally out of the park but are your Telefunken OPT's SE types?
Yes they are SE opt's... Unless I really missed something! lol You can see a picture of them and tell me what you think here, it has the windings wrote on it http://www.diyaudio.com/forums/tubes-valves/200506-anybody-know-telefunken-se-transformer.html
I will check out your drawings, Thanks Bruce.
AL
I will check out your drawings, Thanks Bruce.
AL
So I put the meter on two candidates for the PT.
If I use the beefier PT I could go up to a 5U4 rectifier if needed/wanted or parallel 5Y3's. Other then that it might be a waste of iron for such a small amp. I will however use it, if the voltage suits the project. I am going to attempt to model them in PSUD to see what kind of final voltages I can get between the two.
Here are the voltages measured with nothing attached @118vac.
"Bigger PT"
305-0-305. 65ohm secondaries.
Originally powered Magnavox AMP142 6V6 PPP
"Suitable PT"
327-0-327 220ohm secondaries.
Originally powered 12ax7/6av6/12AU76V6 PP mono amp with 5Y3.
It has a separate heater tap going to the first preamp tube. <Is this of much use?
Any winner with regards to the secondary ohms? I'm assuming less is better
If I use the beefier PT I could go up to a 5U4 rectifier if needed/wanted or parallel 5Y3's. Other then that it might be a waste of iron for such a small amp. I will however use it, if the voltage suits the project. I am going to attempt to model them in PSUD to see what kind of final voltages I can get between the two.
Here are the voltages measured with nothing attached @118vac.
"Bigger PT"
305-0-305. 65ohm secondaries.
Originally powered Magnavox AMP142 6V6 PPP
"Suitable PT"
327-0-327 220ohm secondaries.
Originally powered 12ax7/6av6/12AU76V6 PP mono amp with 5Y3.
It has a separate heater tap going to the first preamp tube. <Is this of much use?
Any winner with regards to the secondary ohms? I'm assuming less is better
If you already heard 6V6 I would suggest you to forget about 6L6. Try something better than 6L6.
Edit: or you can experience for yourself how parallel feedback across curved tube can make it sound well. In such case you would need pentoge stage to drive it. 6AC7, for example.
Edit: or you can experience for yourself how parallel feedback across curved tube can make it sound well. In such case you would need pentoge stage to drive it. 6AC7, for example.
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Ya 6V6 is the plan now. I should have implied 6V6 use between the two.
I figured the 30volt difference between the two could be useful to get a desired B+.
I figured the 30volt difference between the two could be useful to get a desired B+.
NOS 6GH8,6SN7,6CG7,12A*7, 6C4- these are what I have tested anyways.
Also on my list of untested used and NOS are 6CB6,6CS7,6GW8, 12BH7,12BY7,6BH6,6BC5 plus more, I'm just throwing numers at you.
Also on my list of untested used and NOS are 6CB6,6CS7,6GW8, 12BH7,12BY7,6BH6,6BC5 plus more, I'm just throwing numers at you.
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Funny you should ask!
Just a few days ago, I rolled several Rec. tubes in my 6V6SE.
with a 5R4 the B+ was 259vdc.
with a 5Y3 the B+ was 277vdc.
with a 5U4 the B+ was 297vdc.
All conditions were the same except for the rec tube
Just a few days ago, I rolled several Rec. tubes in my 6V6SE.
with a 5R4 the B+ was 259vdc.
with a 5Y3 the B+ was 277vdc.
with a 5U4 the B+ was 297vdc.
All conditions were the same except for the rec tube
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