If you have a frequency response and/or other data maybe someone is interested even more?
Is it an EI core ? copperloss?
Is it an EI core ? copperloss?
I have limited information on the O-Netics transformers I have:
1) 3.3K into 4/8/16 ohms. 100mA gap. Max recommended voltage 300v. It was used in Wright Sound amps, I believe the WPA 3.5 for 2a3 tubes.
2) Level 1 SE OPTs. I think these are 4.5K and for 300b. 450v, 80mA. These are bigger and heavier.
1) 3.3K into 4/8/16 ohms. 100mA gap. Max recommended voltage 300v. It was used in Wright Sound amps, I believe the WPA 3.5 for 2a3 tubes.
2) Level 1 SE OPTs. I think these are 4.5K and for 300b. 450v, 80mA. These are bigger and heavier.
That is very limited indeed. Dos O-Netics give any information about there transformers?
Maybe some pictures?
Now is just a black hole. Gambling.
Maybe some pictures?
Now is just a black hole. Gambling.
A number of members of the "Sound DIY Club" here in Seattle have used O-Netics Iron in their amps and have been "very happy" with the results.
In the interests of full disclosure, Bud Purvine is not only a member of our DIY Club, but he's a friend of mine going back a number of years. However, the fact is that his products are excellent and given the nature of our group, if any of the members had a problem or disliked something about Bud's Iron they certainly would have said something already! (The rules of the Club call for complete candor and honest opinions...however, snide remarks are not welcome.) We're here to try to help our fellow members improve both their skill as well as their systems.
Best Regards,
TerryO
inverse for me i have a James 6123 and a lundhal LL1664 and the first is far more boring , the lundhal gives better details and defined low end than the james . i have LL1664 AM to come and will sell the James and the normal LL1664 soon
inverse for me i have a James 6123 and a lundhal LL1664 and the first is far more boring , the lundhal gives better details and defined low end than the james . i have LL1664 AM to come and will sell the James and the normal LL1664 soon
I haven't heard the James so I can't make that comparison. But in absoiute terms I'm hearing what you are describing - the Lundahl series, like LL1663, LL1664, LL1682 and also the bigger models like the LL1620 have the detail and definition I'm looking for and until anything better comes along - Tango, Tamura, Hashimoto, Monolith or whatever - this is where it's at for me.
i have finally received my LL1664 AM 
after few hours of listening
i have a mixed feeling with them . sure it"s more refined and detailed , even in the low end but sometimes i find it a little harsh . the normal 1664 seems more warm. i will give them few more days before putting one pair of them in the classified
after few hours of listening i have a mixed feeling with them . sure it"s more refined and detailed , even in the low end but sometimes i find it a little harsh . the normal 1664 seems more warm. i will give them few more days before putting one pair of them in the classified
Thanks for posting your LL1664AM results. If you have any updates let us know. I think if I were going beyond the LL1682, LL1620 and LL1664 I have at present, I'd be looking to the cheaper Monolith OPT. I've heard good reports about the Summit at 748.40 Euros pair, and I'd like to hear more about the Etude at 454.80 pair. On their website they list this as 3.3K but I imagine they could do it at 5K.
I actually don't use the 300b - I use 4P1L outputs. I have both PSE 4P1L and SE 4P1L amps, and I tend to listen to the single output stage SE version which needs 5K. I'm actually using the LL1682 which is more like 8K into 8 ohms. Just enough to drive my Alpair 10s and a little more pure in sound. Probably the same difference as 45 and 2a3.
I actually don't use the 300b - I use 4P1L outputs. I have both PSE 4P1L and SE 4P1L amps, and I tend to listen to the single output stage SE version which needs 5K. I'm actually using the LL1682 which is more like 8K into 8 ohms. Just enough to drive my Alpair 10s and a little more pure in sound. Probably the same difference as 45 and 2a3.
i have finally received my LL1664 AM
i have a mixed feeling with them . sure it"s more refined and detailed , even in the low end but sometimes i find it a little harsh . the normal 1664 seems more warm. i will give them few more days before putting one pair of them in the classified
You might want to read this before you throw them out.
I use amorphous core transformers in a lot of my stuff and while I have absolutely no rational explanation these transformers often do not perform well out of the box. Most manufacturers, even ones noted for completely rational behavior will when asked advise running them for an extended period of time with signals comparable to those applied in the actual end use before installation.
I use Lundahl and MM amorphous core transformers and I would estimate 100 hours of use or a dedicated out of system burn in under manufacturer prescribed conditions is needed to get the performance you paid for.
I use Lundahl and MM amorphous core transformers and I would estimate 100 hours of use or a dedicated out of system burn in under manufacturer prescribed conditions is needed to get the performance you paid for.
I guess I should mention that I have no inclination at all to replace them once the requisite number of hours have accrued. This has not always been the case with permalloy and other less exotic core materials, most of these have been replaced or will be when the next system upgrade occurs.
ok i didn't know a magnet needs to burn in but i will do the thing i hate the most , waiting..
the AM version are double the price of the LL1664
Andy , i don't longer use 300B ,AD1 , WE421A , RS241 anymore too much headache with the choice of the driver , ( triode , pentode , DHT or not)
RC coupling , Cap coupling , filament bias , battery fixed bias etc... etc..
too much time in my garage playing with tons of parameters .. i have simplify all of this with a E55L SPUD amp ,one tube , one B+ , battery grid bias and one transformer to choose . but again no free lunch with a SPUD few components means you have to choose them very carefully or it will kill the amp
the AM version are double the price of the LL1664
Andy , i don't longer use 300B ,AD1 , WE421A , RS241 anymore too much headache with the choice of the driver , ( triode , pentode , DHT or not)
RC coupling , Cap coupling , filament bias , battery fixed bias etc... etc..
too much time in my garage playing with tons of parameters .. i have simplify all of this with a E55L SPUD amp ,one tube , one B+ , battery grid bias and one transformer to choose . but again no free lunch with a SPUD few components means you have to choose them very carefully or it will kill the amp
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I suspect problem is not in 100 hours break-in (changes) of transformer properties, it is.timely psychoacoustic adaptation to specific sonic signature of the amorphous core transformer.
It has to be one of the easiest things in the world to verify or disprove to one's own satisfaction. Buy your new OTs. Install one in one channel. Play for 100 hours, then add the other to the other channel. Compare. Pretty simple.
