The am and perm Tamuras are hard to come by even in Japan. Maybe if one is well connected to Japanese DIY cult
. I expected to come back with plenty of DIY stuff, ended up with none. Just vinyl and raw denim I am all for sound engineering reasons, but we are talking about SET amps where I personally grant more leeway for trying out various things, particularly OPTs.
Last edited:
It's not a free lunch.
Having max 1T with 20Hz swing at full power means copperlosses.
I saw a Tribute finemet transformer on the French Elector forum with 0,55dB copperlosses. Is that the standard nowadays?
Having max 1T with 20Hz swing at full power means copperlosses.
I saw a Tribute finemet transformer on the French Elector forum with 0,55dB copperlosses. Is that the standard nowadays?
actually I don't want to feed the troll, but.....
Tribute: calculating copper loss is part of good transformer design.
Tribute OPT's have maximum 0,3 dB insertion loss; most of them quite a bit less when needed for the application.
It seems that you need another free lecture from smoking-amp ...
Stop spoiling this thread by referring to a French forum without proper evidence.
Most likely "your" 0,55 dB insertion loss was for a line output transformer where this specification is an excellent one.
Tribute: calculating copper loss is part of good transformer design.
Tribute OPT's have maximum 0,3 dB insertion loss; most of them quite a bit less when needed for the application.
It seems that you need another free lecture from smoking-amp ...
Stop spoiling this thread by referring to a French forum without proper evidence.
Most likely "your" 0,55 dB insertion loss was for a line output transformer where this specification is an excellent one.
Last edited:
Copper loss is purely resistive, unless there is excess number of turns and too high value of leakage inductance and stray capacitance, I don't see any problem there.
PS. You are continuously criticize other transformer winders all the way around, what is the purpose of this??? You is not only person left in this world with know-how to design audio transformers.
Toroidy.pl are known for very good products. Not that expensive too
How does a toroidal work in SE? I see that they have them on their site... just curious. What benefit would you see over EI?
Thanks,
Kevin
after 2 weeks with my LL1664AM i have swap it with the normal core to see the effect . and yes the amorphous core is better , the sound is smaller , less definition but i have the sweeter sound that i am used to .
so i will sell the Amorphous transfo and keep the cheapest ones ..
amorf power trafos are popular due to very low loss in iron, i am happy to hear what it can mean in audio.
perhaps i my english is not as clear as my amorphous transfo
make no mistake the LL1664AM is better everywhere . but it has a color i don"t like or perhaps it"s the color of the iron core that i 'm used too .
the only place where the iron core is better is in the low end power.
i'm pretty sure that the LL1623AM with the better inductance will be perfect for my needs.. with my little experience with OPT i would say that the LL1664 is equal to a hashimoto and better than my James .
make no mistake the LL1664AM is better everywhere . but it has a color i don"t like or perhaps it"s the color of the iron core that i 'm used too .
the only place where the iron core is better is in the low end power.
i'm pretty sure that the LL1623AM with the better inductance will be perfect for my needs.. with my little experience with OPT i would say that the LL1664 is equal to a hashimoto and better than my James .
Until Lundahl, one day, starts to make transformers with four C cores, his current transformers don't deserve to be compared to James. Nor to Hashimoto.
These are custom ITs made for me by Monolith Magnetics and cost about 3x what the LL1635:20mA cost to be completely fair. They are also much larger physically speaking, probably twice the size, and bi-filar wound with twice the primary inductance (60H).
I've been a bad boy and not done the measurements I should have so with the exception of being entirely flat at 20Hz compared to -2dB for the old IT consider this all completely anecdotal.
It sounds much cleaner, there is more detail starting quite low, it's: "literally like a veil was lifted." All joking aside it offers a substantial increase in apparent resolution and a reduction in transformer distortion/other artifacts. Imaging also improved which was unexpected.
One of these days I will get around to doing some measurements including FFTs and frequency response at various levels. I imagine this will reveal a rather significant reduction in distortion of all kinds in the output of the driver stage. Other than more extended frequency response this is probably the main benefit of the upgrade.
If nothing else I feel pretty confident in recommending Monolith products, beyond pleased.
perhaps i my english is not as clear as my amorphous transfo
make no mistake the LL1664AM is better everywhere . but it has a color i don"t like or perhaps it"s the color of the iron core that i 'm used too .
the only place where the iron core is better is in the low end power.
i'm pretty sure that the LL1623AM with the better inductance will be perfect for my needs.. with my little experience with OPT i would say that the LL1664 is equal to a hashimoto and better than my James .
makes sense, no huge magnetic grains to moveOne thing i don´t understand, why so long burn in. From physics view
I thought twin bobbin C is better for symmetry, unless yours single bobbin are done with pi winding. Basically same like EI
It's interesting you bring up interstages. Are you finding any drop off in bass response with amorphous core interstages, or does that only apply in the case of OPTs? Would, for instance, an amorphous Lundahl interstage retain all the bass energy that Juanitox is missing in the OPT?
I forgot to mention, the winding (unused) taps are "dead weight", worsening internal parasitic LC values.
Taps are more convenient though
(4,8,16r plugs on chassis)
One thing i don´t understand, why so long burn in. From physics view
I thought twin bobbin C is better for symmetry, unless yours single bobbin are done with pi winding. Basically same like EI
I was not talking about bobbins, windings or core materials. I was talking about *number* of core pieces. As far as I'm aware, all reputable output transformer manufacturers who employ C cores use *four* C cores per one transformer. Lundahl uses *two* C cores per one transformer. He must have his own reasons for doing so. But then, let's compare apples to apples. Or let's compare apples to oranges and say that two C cores match or even outperform four C cores. Logical?
I would be concerned rather about proper "weight" of core used; hopefully lundahl uses right weight of iron, to make opt not bass thin.
One reason i see, is lower manufacturing cost-simplicity, you´re making just one bobbin.
Funny thing, lundahl even makes cores himself from sheet metals bought on drums. Everybody else just buys finshed cores or EIs
One reason i see, is lower manufacturing cost-simplicity, you´re making just one bobbin.
Funny thing, lundahl even makes cores himself from sheet metals bought on drums. Everybody else just buys finshed cores or EIs
Last edited: