Hello guys, I will be buiding a single ended tube amp and I have three output tubes: EL84, 6P3S-E and old EL34. What tube will be best choice, what tube sounds better? And second question, how to calculate and wind good output transformer? I have unwinded pretty big mains tranny. It have middle core about 4x3cm. Will be this enough? Thank you for answers and good weekend 
The EL34 would be my first choice. You'll get more power and not need such a high primary impedance output transformer. Of course, you didn't say how much power you want, whether you want to run these as triodes, etc.
You pay a transformer winder for the transformer you need.
Low power output tubes are disregard due low SPL capabilities and anemic bass narrowing the speakers choice, so it let you with the EL34 only that will offer Triode 6W conservative, that is enough for a easy to find 100dB speaker as Klipsch RF7 or used Chorus or Tekton Lore.
Also with EL34 you can use a plethora of others Pentodes tubes as 6550,KT88/90/120/150 and the cheap 807 with adapter, not a neglegible feature.
In view this sound quality not important, but EL34 is my favorite sound due image and sweet harmonics.
Also with EL34 you can use a plethora of others Pentodes tubes as 6550,KT88/90/120/150 and the cheap 807 with adapter, not a neglegible feature.
In view this sound quality not important, but EL34 is my favorite sound due image and sweet harmonics.
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For good bass in SE mode, You can use big iron with power, IMO, 10-20 time more than amps output power. /for 3 W You can use OT with about 40-50 W/. In my SE 2A3 RCA with 3 W, I use OT 25W and and band is 10 -about 60000 Hz with +- 0 % decreasing level of amplitude.
The higher the impedance, higher is the difficulty to achieve a successful opt . The lowest impedance tube you have is the EL34 3.5k . Consider also this
Biến thế xuất am 2k5 - 3K5 EL34 6P3C FU7 FU50 2A3 300B
23000 dong =1$ ,may be Google translation can help.
Biến thế xuất am 2k5 - 3K5 EL34 6P3C FU7 FU50 2A3 300B
23000 dong =1$ ,may be Google translation can help.
The size of tube eg EL34 vs EL84 has no influence on bass performance, that is entirely down to the output transformer.
I wouldn't use a recycled mains transformer as the laminations will be too thick and impinge on treble performance.
As frequency goes up then the laminations need to get thinner, (of course you'll need more for the same overall size).
Also for good bass, then size is everything. As the frequency halves then you need to double the transformer mass.
Attempting to wind your own transformer with no engineering background, especially for single ended (which needs a magnetic gap) is likely to result in disappointing performance, but by all means do give it a go.
I wouldn't use a recycled mains transformer as the laminations will be too thick and impinge on treble performance.
As frequency goes up then the laminations need to get thinner, (of course you'll need more for the same overall size).
Also for good bass, then size is everything. As the frequency halves then you need to double the transformer mass.
Attempting to wind your own transformer with no engineering background, especially for single ended (which needs a magnetic gap) is likely to result in disappointing performance, but by all means do give it a go.
The 6P3SE has the sound of a 6L6 which is different from the EL34 family of tubes. I like the sound of the 6P3SE in SE and have a couple of amps I use them in. Great value in NOS tubes. Personally depending on brand I like the family of EL34 tubes in a SE amplifier best. Right now I am using Gold Lion KT77's in one of my amplifiers and am enjoying the sound. I have 2 EL84 type amplifiers in both SE and PP. A nice tube as well. You will not go wrong with any of the 3. In SE you will have much more power with either the 6P3SE and EL34.
I use 6P3S (not the 6P3S-E) for most of my builds (or KT88/120) and love the sound/price ratio. I only build push pull amps though. I'd go with a 6P43P over the EL84. Never built an EL34 amp but it looks like triode mode will put out more power than a 6L6.
I use toroidal mains transformers as the OPTs...
I use toroidal mains transformers as the OPTs...
Hello guys, I will be buiding a single ended tube amp and I have three output tubes: EL84, 6P3S-E and old EL34. What tube will be best choice, what tube sounds better? And second question, how to calculate and wind good output transformer? I have unwinded pretty big mains tranny. It have middle core about 4x3cm. Will be this enough? Thank you for answers and good weekend
simulate - Triode / Pentode Loadline Simulator v.1.0 (20161216 [url]www.trioda.com)[/url]
shopping - Toroidne transformatory | TME Slovakia s.r.o. - Elektronicke sučiastky
it is not worth to make own transformers, these are cheap and quite good
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Hi,
Do you would inform me how I would choose a Toroidal OPT for 6C33??
(600 ohms primary, secondary 4 and 8 ohms)
If you use a power toroid you much choose one Zout. You must balance the current in the primary with either CCS cathode biasing, or an audio bias board such as the ones from audioamp.eu, and it must be push pull.
The Triad VPT24-10420 will give you 735R:8R if wired for 24V secondary. ((230/24)^2)8=735
VPT24-10420 Triad Magnetics | Transformers | DigiKey
The Triad VPT18-13800 will give you 653R:4R if wired for 18V secondary. ((230/18)^2)4=653
VPT18-13800 Triad Magnetics | Transformers | DigiKey
Both are 250VA which might seem overkill but they are designed for 50Hz, therefore they need to be oversized.
I would suggest using a higher Raa though. Say 1k or so.
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