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opt for 45 tube

45

Member
2008-12-18 2:29 am
UK
I have doubts
which of these two transformer choose
for a 45tube amp.
* Lundahl - LL1663 .......... $ 354,938
* JS-6113HS JAMES .......... $ 169.00
This justified the effort
in the price difference

thanks in advance

Pedro..

The difference is well justified for me. The James has poor performance at low and high frequency in comparison, especially regarding distortion.
 
Just a pitty that Lundahl dosn't give a frequency response. Copper losses for a small transformer as the ll1663 is reasonable low (about 0,3dB) but still not top.
Anyway the James is a bargain compared to the Lundahl and i think more then 300 dollar is not justified for a small transformer as the Lundahl is. I see no special futures.........or specifications.
 
Hello - do you mean solved as in you have bought an OPT?

If you are still looking, I can add my experiences. I found the best sounding one of the ones I have used was an O-netics "commercial" SE OPT which is the cheapest that Bud makes. This is 3.5K - you may want 5K. I was using my transformers with a 300b. The next best was either AudioNote Trans-152 or Lundahl LL1620. Then LL1623. Last LL1682, which I didn't get to sound good. I haven't tried the James, but I would like to. In your position, and only going on the comments of others, I would buy the James.

There was a long thread about SE OPTs for 300b. It should give you some ideas. It was a (difficult!!) attempt to look at any comparative reviews of SE OPTs. It included some shootouts.

http://www.diyaudio.com/forums/tubes-valves/6457-best-300b-se-opt.html
 
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Hello - do you mean solved as in you have bought an OPT?

If you are still looking, I can add my experiences. I found the best sounding one of the ones I have used was an O-netics "commercial" SE OPT which is the cheapest that Bud makes. This is 3.5K - you may want 5K. I was using my transformers with a 300b. The next best was either AudioNote Trans-152 or Lundahl LL1620. Then LL1623. Last LL1682, which I didn't get to sound good. I haven't tried the James, but I would like to. In your position, and only going on the comments of others, I would buy the James.

There was a long thread about SE OPTs for 300b. It should give you some ideas. It was a (difficult!!) attempt to look at any comparative reviews of SE OPTs. It included some shootouts.

http://www.diyaudio.com/forums/tubes-valves/6457-best-300b-se-opt.html

Thanks Andy and everyone for your input
I will read this post

I am currently using a 3k5 tomikos
1 Tomiko 1 7K 3 5K SE Single End Output Transformer 45 UX 245 UX 350 UX 250 50 | eBay

what is your opinion about them
will be worth replacing
 
Thanks Andy and everyone for your input
I will read this post

I am currently using a 3k5 tomikos
1 Tomiko 1 7K 3 5K SE Single End Output Transformer 45 UX 245 UX 350 UX 250 50 | eBay

what is your opinion about them
will be worth replacing

The frequency response is a bit weird.....maybe somebody made a mistake. Also de dcr is high, 405 Ohm. That will mean high copper losses. I guess about 10% (or even more) of your signal is lost in heat. Anyway great price so no need to complain.
 

45

Member
2008-12-18 2:29 am
UK
Hello - do you mean solved as in you have bought an OPT?

If you are still looking, I can add my experiences. I found the best sounding one of the ones I have used was an O-netics "commercial" SE OPT which is the cheapest that Bud makes. This is 3.5K - you may want 5K. I was using my transformers with a 300b. The next best was either AudioNote Trans-152 or Lundahl LL1620. Then LL1623. Last LL1682, which I didn't get to sound good. I haven't tried the James, but I would like to. In your position, and only going on the comments of others, I would buy the James.

There was a long thread about SE OPTs for 300b. It should give you some ideas. It was a (difficult!!) attempt to look at any comparative reviews of SE OPTs. It included some shootouts.

http://www.diyaudio.com/forums/tubes-valves/6457-best-300b-se-opt.html

AudioNote transformers for DIY are simply overrated. They are expensive and give poor performance both on the bench and musically in comparison to most of their class and cheaper! Nothing to do with original Audio Japan......
Many people do not realize it until they try with some proper full range speakers (i.e a good 2 or 3 ways speaker).
You are right: everyone will give his own view and it will hardly agree with that of the others!:D
 
AudioNote transformers for DIY are simply overrated. They are expensive and give poor performance both on the bench and musically in comparison to most of their class and cheaper! Nothing to do with original Audio Japan......
Many people do not realize it until they try with some proper full range speakers (i.e a good 2 or 3 ways speaker).
You are right: everyone will give his own view and it will hardly agree with that of the others!:D

AN makes much different transformers, how many consider you as "bad" and do you have measurements of it?
 
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AudioNote transformers for DIY are simply overrated. They are expensive and give poor performance both on the bench and musically in comparison to most of their class and cheaper! Nothing to do with original Audio Japan......
:D

I hear you. On the other hand, the AN Trans-300 did win the ETF shootout against Tango, Tamura etc. The Trans-152 I have are BIG, like 110x96x120, and are 2.5K. They sound pretty much like a big SE transformer - good bass, decent mids, treble OK but less subtle than a smaller transformer. They are reasonably musical, in fact, and I wouldn't call them bad. The Lundahl LL1620 is probably a touch better, but not more than that. I could go either way. But O-netics "commercial" is a level up. It's a small transformer 84x76x64 and actually that's the same size as the Transcendar 3K.

As for James, they do a small transformer 6112HS (6113HS for 45) 72x72x85 and a medium one 6123HS 80x90x110. Both have been well reviewed by users. Very good value. I haven't heard them myself.

I really don't know how much size matters. I don't know if it's possible to say smaller = better treble. I'm guessing many OPTs might break that rule if it is a rule at all.
 

45

Member
2008-12-18 2:29 am
UK
I hear you. On the other hand, the AN Trans-300 did win the ETF shootout against Tango, Tamura etc. The Trans-152 I have are BIG, like 110x96x120, and are 2.5K. They sound pretty much like a big SE transformer - good bass, decent mids, treble OK but less subtle than a smaller transformer. They are reasonably musical, in fact, and I wouldn't call them bad. The Lundahl LL1620 is probably a touch better, but not more than that. I could go either way. But O-netics "commercial" is a level up. It's a small transformer 84x76x64 and actually that's the same size as the Transcendar 3K.

As for James, they do a small transformer 6112HS (6113HS for 45) 72x72x85 and a medium one 6123HS 80x90x110. Both have been well reviewed by users. Very good value. I haven't heard them myself.

I really don't know how much size matters. I don't know if it's possible to say smaller = better treble. I'm guessing many OPTs might break that rule if it is a rule at all.
I don't know O' Netics so I cannot comment. The Trans 152 uses a bigger core than average (for its specs) and lower number of turns. However the bigger core size is not enough to compesate for lower number of turns. Its primary inductance is pretty low for such big transformer and the performance at low frequency is between average and mediocre for my standards. On the other end the high frequency roll-off is not smooth however this is not necessarily a problem, in particular if no feedback is used. To me they didn't sound good. Bass perfomance was not good. The Trans 300 uses HiB core but still at low frequency is not as good as its rivals. Many think that SET amps don't have good bass perfomance because of the damping factor but this is not actually true. Damping factor plays a minor role if you have the right speakers. OPT performance and power supply are the main factors.....

Cheers
 
I also vote for O-netics irons. Months ago I ordered 5K SE level 2 M3 transformers and they sound incredibly!
Much better that everything else I tried. Please don't ask which the others transformers were... but I can assure you they were expensive (nickel core).
Don't look elsewhere. His M6 are cheap enough and still great if one don't want to spend a fortune.
 
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AudioNote transformers for DIY are simply overrated. They are expensive and give poor performance both on the bench and musically in comparison to most of their class and cheaper! Nothing to do with original Audio Japan......
Many people do not realize it until they try with some proper full range speakers (i.e a good 2 or 3 ways speaker).

my speakers are Lowther EX4 in Hedlund horns
[IMGDEAD]http://img823.imageshack.us/img823/6392/img0052tj.jpg[/IMGDEAD]




fvale
I also vote for O-netics irons. Months ago I ordered 5K SE level 2 M3 transformers and they sound incredibly!

where I can get O-Netics
 
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