Ok, with hindsight that wasn't actually fair 
, my definitions are-
"HOT" is when it's physically painful to touch the case during/ immediately after use.
"Warm" is when you can touch it without getting burnt.
So on that basis, 'always at least warm' is a better statement. But I do currently have one you turn off 5 mins before picking up!
I have never been lucky enough to have a tube amp that ran barely warm
- all have been Chinese for reasons of economy. But I've been reasonably happy with them.
TNSTAAFL but the ingredients may be cheaper depending on where you dine
Cobra2 that thread has come on a long way, have you got anywhere with alternative OPT's? (chinese or otherwise) - I'm 1/2 looking to upgrade too, but I cant bear to spend too much money on my SE amp. You have P-P a much more sensible propsition IMHO - maybe thats why its cooler too?
Andy
, my definitions are-"HOT" is when it's physically painful to touch the case during/ immediately after use.
"Warm" is when you can touch it without getting burnt.
So on that basis, 'always at least warm' is a better statement. But I do currently have one you turn off 5 mins before picking up!
I have never been lucky enough to have a tube amp that ran barely warm
- all have been Chinese for reasons of economy. But I've been reasonably happy with them. TNSTAAFL but the ingredients may be cheaper depending on where you dine
Cobra2 that thread has come on a long way, have you got anywhere with alternative OPT's? (chinese or otherwise) - I'm 1/2 looking to upgrade too, but I cant bear to spend too much money on my SE amp. You have P-P a much more sensible propsition IMHO - maybe thats why its cooler too?
Andy
It is probably far from class A... 
I tried some variations but did not manage to make it sound good, even with all Mullard...and have run out of parts (3W resistors).
I'm thinking of new trafos, with U.L. windings, but they will probably not fit in the rear chamber...
So I will probably break it for parts, make a new chassi, and make a new amp...
Worst thing is, there are not much to save...
What a waste.
Arne K
I tried some variations but did not manage to make it sound good, even with all Mullard...and have run out of parts (3W resistors).
I'm thinking of new trafos, with U.L. windings, but they will probably not fit in the rear chamber...
So I will probably break it for parts, make a new chassi, and make a new amp...
Worst thing is, there are not much to save...
What a waste.
Arne K
hi Cobra2 & andrew_whitham,
most china made tube amp use re-use 0.5mm Hi-B, sorry not cold roll lamination for power transformers. They will hot low efficiency but will accept in europe or other cold place. If use this one in East Asia, will very easy to burn.
Normally their OPT was use old HV power plant large size transformer broken lamination & made for small size, so why china made audio amp so cheap in price.
If every people use nippon steel lamination U can very easy to caculate How much for one tone of lamination, plus labour, chassis & parts. How can they do in this price!
I was member of this forum, I only like to prepare good parts to all diyers. since we paid much time & effort for our amp. If the last stage output transformers was not good. Will U satify!!!!
andrew_whitham, take a look for my 4N & 5N monocrystalline silver wire. U will see the tailor made Clone Audionote kits coming use this secondary silver wire OPT.
OPT will had Nickel base Nano amorphous & 0.03mm ultra Hi-B lamination.
May be U will think this parts was expensive. But If U like the best pls considerate, If U like a standard amp, I will suggest back to choose china amde tube amp. But PP amp only. SE amp need high quality of OPT. Looks china Old used core cannot fit the good standard.
thx
thomas
most china made tube amp use re-use 0.5mm Hi-B, sorry not cold roll lamination for power transformers. They will hot low efficiency but will accept in europe or other cold place. If use this one in East Asia, will very easy to burn.
Normally their OPT was use old HV power plant large size transformer broken lamination & made for small size, so why china made audio amp so cheap in price.
If every people use nippon steel lamination U can very easy to caculate How much for one tone of lamination, plus labour, chassis & parts. How can they do in this price!
I was member of this forum, I only like to prepare good parts to all diyers. since we paid much time & effort for our amp. If the last stage output transformers was not good. Will U satify!!!!
andrew_whitham, take a look for my 4N & 5N monocrystalline silver wire. U will see the tailor made Clone Audionote kits coming use this secondary silver wire OPT.
OPT will had Nickel base Nano amorphous & 0.03mm ultra Hi-B lamination.
May be U will think this parts was expensive. But If U like the best pls considerate, If U like a standard amp, I will suggest back to choose china amde tube amp. But PP amp only. SE amp need high quality of OPT. Looks china Old used core cannot fit the good standard.
thx
thomas
An externally hosted image should be here but it was not working when we last tested it.
hi,.
photos show diffewrent thickness of audio laminations.
the middle one was Z11/M6 core---0.3mm.
remain two size one was famous japan audio transformers use 0.2~0.23mm Hi-B.
the thinnest was Ultra HI-B.
0.03mm
U can compare with the paper.
thx
thomas
photos show diffewrent thickness of audio laminations.
the middle one was Z11/M6 core---0.3mm.
remain two size one was famous japan audio transformers use 0.2~0.23mm Hi-B.
the thinnest was Ultra HI-B.
0.03mm
U can compare with the paper.
thx
thomas
An externally hosted image should be here but it was not working when we last tested it.
Cobra2 said:It is probably far from class A...
I looked at this on the PC - I'll leave some comments on the other thead!
tube-lover said:
Already did that! Yes expensive at the moment but MMMMMmmmmm very nice. Not sure I can justify silver wire though
If I only had deeper pockets!
Aint that a fact - this is actually borne out by a quick look at the response curves (When / if you can get them) its expensive too make a good SE amp - yes, I know that NOW!
Perhaps the subject for another thread - what is the cheapest SE trafo that'll pass 100ma and is less than 1b down at (for example) 20Hz?
Andy
Hey-Hey!!!,
Seems that there's three things contributing to the price of a good OPT. R&D needed for a good design, labor to make it, and materials.
The R&D is easy enough to side-step. I have had a few high-performance vintage units unwound to see *EXACTLY* how they're put together. I wound up with some very nice outputs, at about 1/5 of the price quoted by the audio-only butthead in Phila.
Labor is also easy enough to get around...NC controlled winders are very capable and make short work of even complex coils. In the US there will be limits on reducing labor cost, but the same winders that crank out cheap power Iron in China can also take on a good OPT.
Materials are a bit harder to get around. Cu is always going to have a minimum, as well as good steel ( or Ni, or some other exotic ).
cheers,
Douglas
Seems that there's three things contributing to the price of a good OPT. R&D needed for a good design, labor to make it, and materials.
The R&D is easy enough to side-step. I have had a few high-performance vintage units unwound to see *EXACTLY* how they're put together. I wound up with some very nice outputs, at about 1/5 of the price quoted by the audio-only butthead in Phila.
Labor is also easy enough to get around...NC controlled winders are very capable and make short work of even complex coils. In the US there will be limits on reducing labor cost, but the same winders that crank out cheap power Iron in China can also take on a good OPT.
Materials are a bit harder to get around. Cu is always going to have a minimum, as well as good steel ( or Ni, or some other exotic ).
cheers,
Douglas
Bandersnatch said:
AHhhh now thats a point copper is MORE expensive in China than anywhere else - as is steel for that matter (+10%)
automated assembly means that the labour costs associated with chinese production are not always as significant as people imagine
WOW this is just like being at work! S'pose when you think about it, a lot of the cost in a trafo is material. Which probably explains why they're all (approx) the same cost once you ship them
As a side note then for the UK based people. www.hificollective.co.uk is selling Audionote ones from £55 each are these any good?
Andy
hi andrew_whitham,
If U buy audionote OPT, that's a good idea. Since before audionote UK & audionote Japan ( Kondo now) broken down all the OPT was made in japan or said Data was from japan. Until now still some of Kondo tube amp still use Tango transformers.
Cheap audionote OPT was not made in UK. THis I can let U konw. The spec was not good. If U like to buy second hand OPT. I suggest U buy higher level one.
I can let U know a good Output mainly was the material. Second was trhe winding techical. If the material of the OPT was not good. Winding method only can compensate some of the problem of the OPT.
for example a good OPT.
SE OPT.
1. Large Henry.( But will not effect the HF, Little more bass will made the sound soft, increase the density of MF).
2. Low DCR, since the plate of the power tube was directly loading with the OPT. if the HV(B+) pass the OPT had too large voltage drop, efficiency will lower, weak bass, weak dynamic.
3. Low capacitance. Filter HF.
4. Low Leakage.Less phase shift.
5. High efficiency, everyone will know high efficiency better.
6. Low phase shift The singer & instrument size pin point will better.
Layer material of audio Transformers,
Is thicker or thinner will better?????
can one can share????
If the material was not good. How to Do. most people think OPT must must very large to colect better, is it right, Yes, some was right. Use large core can do this. But large core will effect the time delay from inner layer wire to outer wire reaction with the core. Any people will know?????
Take a look of Audionote Ongaku Japan Their OPT size was small core, very dynamic, fast bass, detail with silver wire. Also had 27 Watts Power OPT.
thx
thomas
If U buy audionote OPT, that's a good idea. Since before audionote UK & audionote Japan ( Kondo now) broken down all the OPT was made in japan or said Data was from japan. Until now still some of Kondo tube amp still use Tango transformers.
Cheap audionote OPT was not made in UK. THis I can let U konw. The spec was not good. If U like to buy second hand OPT. I suggest U buy higher level one.
I can let U know a good Output mainly was the material. Second was trhe winding techical. If the material of the OPT was not good. Winding method only can compensate some of the problem of the OPT.
for example a good OPT.
SE OPT.
1. Large Henry.( But will not effect the HF, Little more bass will made the sound soft, increase the density of MF).
2. Low DCR, since the plate of the power tube was directly loading with the OPT. if the HV(B+) pass the OPT had too large voltage drop, efficiency will lower, weak bass, weak dynamic.
3. Low capacitance. Filter HF.
4. Low Leakage.Less phase shift.
5. High efficiency, everyone will know high efficiency better.
6. Low phase shift The singer & instrument size pin point will better.
Layer material of audio Transformers,
Is thicker or thinner will better?????
can one can share????
If the material was not good. How to Do. most people think OPT must must very large to colect better, is it right, Yes, some was right. Use large core can do this. But large core will effect the time delay from inner layer wire to outer wire reaction with the core. Any people will know?????
Take a look of Audionote Ongaku Japan Their OPT size was small core, very dynamic, fast bass, detail with silver wire. Also had 27 Watts Power OPT.
thx
thomas
An externally hosted image should be here but it was not working when we last tested it.
close look for U to compare the size of OPT for 27watts SE with 211 tubes.
thx
thomas
thx
thomas
An externally hosted image should be here but it was not working when we last tested it.
output information
An output transformer is 90% 0f what is wrong with an amp and only 70% of what is right. Toroid's will not work for SE because they have no gap and more than 10 ma will start eating the available flux, required for low frequencies. Now, if the toroid core has been cut and a gap has been enforced they will work just fine but you must use thick, many stranded pvc coated ground buss wire in your signal circuit to provide enough locally loitering electrons to supply the rather sharp transient attack of a gapped toroid.
Bud
An output transformer is 90% 0f what is wrong with an amp and only 70% of what is right. Toroid's will not work for SE because they have no gap and more than 10 ma will start eating the available flux, required for low frequencies. Now, if the toroid core has been cut and a gap has been enforced they will work just fine but you must use thick, many stranded pvc coated ground buss wire in your signal circuit to provide enough locally loitering electrons to supply the rather sharp transient attack of a gapped toroid.
Bud
hi,
looks
there will ohad one band use toroid core for SE OPT.
pls take a look.
http://www.plitron.com/audio_se.asp
Single Ended Toroidal Output Transformers
--------------------------------------------------------------------------------
Extensive research and development over a three year period was conducted by Plitron and Menno Vanderveen into the application of toroidal technology for single ended output transformers. This included development of new toroidal cores, resulting in transformers exhibiting constant and linear magnetic behavior and tolerance to current and voltage changes. Innovative winding and constructional techniques were also developed. The result provides significant performance advantages: clear, high frequency behavior, the result of critical damping, controlled high frequency roll-off and phase coherence; clean, solid bass response due to the large and constant factored primary inductance; neutral and uncolored midband, due in part to the carefully controlled magnetics inherent in toroidal construction; undistorted sound rich in details and vivid in spatial response.
Short form specifications are shown below. For full, individual spec sheets in html, click the part number; for pdf versions click in dowload section.
SPECIFICATIONS
3050-SE 3035-SE 3025-SE
Tube Type 300B
Primary Impedance 5060 ohm 3490 ohm 2490
Power 13 W 13 W 13
Secondary Inductance 4 + 8 ohm 4 + 8 ohm 4 + 8 ohm
Turns Ratio (Np:Ns) 35.55:1 29.52:1 24.96:1
Power Bandwidth (-3dB) 20 Hz -134 kHz 20 Hz -142 kHz 20 Hz -147 kHz
Insertion Loss 0.17 dB 0.17 dB 0.18 dB
Quality Factor 410,000 410,000 327,300
Case Aluminum, textured black finish, 152.4 x 88.9
Download
PAT3050SE.pdf PAT3035SE.pdf PAT3025SE.pdf
--------------------------------------------------------------------------------
3050-SE | 3035-SE | 3025-SE
Standard Series (push-pull) | Single-ended | Specialist Range | Special Designs
Power Transformers | Chokes | Chassis for Tube Amplifiers
Circuit Board for 70W & 100W Amplifiers | Electrostatics | Distribution
Audio Books | Audio Articles | Testimonials | Photo Gallery
thx
thomas
looks
there will ohad one band use toroid core for SE OPT.
pls take a look.
http://www.plitron.com/audio_se.asp
Single Ended Toroidal Output Transformers
--------------------------------------------------------------------------------
Extensive research and development over a three year period was conducted by Plitron and Menno Vanderveen into the application of toroidal technology for single ended output transformers. This included development of new toroidal cores, resulting in transformers exhibiting constant and linear magnetic behavior and tolerance to current and voltage changes. Innovative winding and constructional techniques were also developed. The result provides significant performance advantages: clear, high frequency behavior, the result of critical damping, controlled high frequency roll-off and phase coherence; clean, solid bass response due to the large and constant factored primary inductance; neutral and uncolored midband, due in part to the carefully controlled magnetics inherent in toroidal construction; undistorted sound rich in details and vivid in spatial response.
Short form specifications are shown below. For full, individual spec sheets in html, click the part number; for pdf versions click in dowload section.
SPECIFICATIONS
3050-SE 3035-SE 3025-SE
Tube Type 300B
Primary Impedance 5060 ohm 3490 ohm 2490
Power 13 W 13 W 13
Secondary Inductance 4 + 8 ohm 4 + 8 ohm 4 + 8 ohm
Turns Ratio (Np:Ns) 35.55:1 29.52:1 24.96:1
Power Bandwidth (-3dB) 20 Hz -134 kHz 20 Hz -142 kHz 20 Hz -147 kHz
Insertion Loss 0.17 dB 0.17 dB 0.18 dB
Quality Factor 410,000 410,000 327,300
Case Aluminum, textured black finish, 152.4 x 88.9
Download
PAT3050SE.pdf PAT3035SE.pdf PAT3025SE.pdf
--------------------------------------------------------------------------------
3050-SE | 3035-SE | 3025-SE
Standard Series (push-pull) | Single-ended | Specialist Range | Special Designs
Power Transformers | Chokes | Chassis for Tube Amplifiers
Circuit Board for 70W & 100W Amplifiers | Electrostatics | Distribution
Audio Books | Audio Articles | Testimonials | Photo Gallery
thx
thomas
this is an interesting thread, I saw those toroids on ebay, almost bought some, glad I didn't.
I have had the 'mars' audio ones, with the silvery chrome caps, from ebay, and china, and they are ok, they seem to have an air gap, sounded acceptable, bit small
and eastern audio, again they were nicely made and small
great value for money
I like the one about the audio butt from phila, I wonder who that could be
but yes the price of shipping from china/hongkers is a little prohibitive, its ok via sea but takes a month or two, and post via air, like you say, it offsets significantly any price advantage.
there is good stuff out there from china, there is bad, but that's the same in any country. I got some uk transformers, and unwound a bust one, the layers were insulated with paper masking tape.
quoting svein
"Primary DC resistance was 230 + 255 Ohm, probably an indication that interleaving has not been considered ?"
dc resistance has nothing to do with interleaving.
its to do with
1/ metal, copper, silver, etc.
2/ area, how thick wires are
4/ length of wire ie how many turns, size of core
for a good design, less than 5% of nominal impedance
interleaving is to do with extending hi frequency, which is to do with capacitance and inductance, which affects ac.
if its got a good frequency, it will be well interleaved, so rest easy
I have had the 'mars' audio ones, with the silvery chrome caps, from ebay, and china, and they are ok, they seem to have an air gap, sounded acceptable, bit small
and eastern audio, again they were nicely made and small
great value for money
I like the one about the audio butt from phila, I wonder who that could be
but yes the price of shipping from china/hongkers is a little prohibitive, its ok via sea but takes a month or two, and post via air, like you say, it offsets significantly any price advantage.
there is good stuff out there from china, there is bad, but that's the same in any country. I got some uk transformers, and unwound a bust one, the layers were insulated with paper masking tape.
quoting svein
"Primary DC resistance was 230 + 255 Ohm, probably an indication that interleaving has not been considered ?"
dc resistance has nothing to do with interleaving.
its to do with
1/ metal, copper, silver, etc.
2/ area, how thick wires are
4/ length of wire ie how many turns, size of core
for a good design, less than 5% of nominal impedance
interleaving is to do with extending hi frequency, which is to do with capacitance and inductance, which affects ac.
if its got a good frequency, it will be well interleaved, so rest easy
lt cdr data said:
I found that sometimes a clear distinction is not made between
interleaving and sectionalising. If Svein meant the latter, then it could be that one usually does not merely connect several primary sections in series from bottom to top, but try to intermix such that the dc resistances are as equal as possible.
Further, I wonder what magic there is about silver wire? 5% higher conductivity? I read that in China Cu wire is expensive, but over here there is quite a cost penalty with silver, also because of lower production volumes. As far as I am aware (under correction) silver wire is stiffer than copper wire, which could mean that on the winding flats greater air gaps might exist, influencing C and leakage.
Johan,
I don't know if this is true, but I ran across this comment on the Electra-Print site earlier this week.
"Silver wire audio transformers have been considered, for many years, to make an improvement in audio reproduction. Due to silver’s higher sensitivity to flux change (200%) it is able to reproduce lower level information produced by the output stage. This resulted in an audible increase of the low level higher harmonics that do exist from various musical instruments."
Looney
I don't know how a very small increase in conductivity leads to 200% change in flux
I know EP seem to be respected, and their single ended output tx's are huge, but I had a preamp output transformer that sounded pretty horrid.
def. inferior to simple C-R coupling, squashed dynamics, not good at all, that may not be EP's fault, I have heard others talk of transformer coupled pre's doing the same.
also, if those low level higher harmonics are above the cut off point, too that makes them hard to hear anyway
if anyone gives a blanket statement like that, they need to provide proof of why it is, otherwise, it don't count for nothing, I don't have time to go thro the equations, even if I can find the relevant ones
Looneytunes said:
This is pure Sales talk..... the question one should ask "at what primary winding resistance does harmonic distortion increase" ?
With anode resistances of o/p tubes around several kohms, and good transformer windings a few Ohms difference between Cu & Ag amounts to nothing.
Pouring cold water over this, this would even include mic and mixing transformers where Cu windings use 99.99%. The odd bit of silver (Ag) thrown in an output transformer isn't going to make any difference.
richj
its mostly been championed by qvortrop, hardly anyone else.
considered to make an improvement?
by whom,
when
where?
proven?
the harder the sell the more desparate the company
I lose respect for companies who talk without backup and avoid them like the plague
now patrick turner, turneraudio, in australia, there's an honest man who talks sense
considered to make an improvement?
by whom,
when
where?
proven?
the harder the sell the more desparate the company
I lose respect for companies who talk without backup and avoid them like the plague
now patrick turner, turneraudio, in australia, there's an honest man who talks sense
I notice the direction of the thread has wandered...The law of diminishing reTURNS. Suggest reading Radiotron handbk 4th ed page 206-214. (I now it's vintage but still holds).
Far more influencial than winding resistances is designing for low leakage inductance and choosing an appropriate grade of sil iron.
The golden formulas used by Partridge and others are still used by majority of transformer manufacturers, now extrapolated for the modern in software form....Some transformer designers (UK) still uses slide rules for calculations and despite tolerances, the transformers are 1st class sound performers. No software. No quibbles. It’s all about using math as a tool not silver.
Is everyone quite sure that correct iron is used for the application ?
No myth behind this one and very well known for eons, that Lundahl (Swedish iron) is the best sounding iron around.
richj
Far more influencial than winding resistances is designing for low leakage inductance and choosing an appropriate grade of sil iron.
The golden formulas used by Partridge and others are still used by majority of transformer manufacturers, now extrapolated for the modern in software form....Some transformer designers (UK) still uses slide rules for calculations and despite tolerances, the transformers are 1st class sound performers. No software. No quibbles. It’s all about using math as a tool not silver.
Is everyone quite sure that correct iron is used for the application ?
No myth behind this one and very well known for eons, that Lundahl (Swedish iron) is the best sounding iron around.
richj
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