Zero Box Autoformers w/ Theos and PrimaLuna Dialogue HP Tubed Integrated?

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Homer_Skins

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Hey gang,

I did a search on here to see who may be using a set of Zero Box Autoformers in conjunction with Theos and a PrimaLuna Dialogue HP Integrated tube amplifier but couldn't find anything. Anybody try such a combination and can you tell me your results? Paul Speltz has a lot of testimonies on his AntiCables site as well as ZeroImpedance.com. One cat was using the Autoformers in conjunction with a tubed amplifier and ML CLS IIz Speakers.

I would appreciate any information at all from anybody with experience in having a set of Autoformers in their system.

Thanks! Dana
 
If your amp is not a good match for your speakers, an autoformer will make it work, but it's a band-aid fix.
You should really get the right amp for them or change the speakers so the amp can drive them properly.

Cheers George
 
For grins I test drove a pair of CLS IIz's with a simple 8 watt SET amp.

I can't imagine the Prima Luna not having sufficient power to drive a pair of far easier to drive Theos to ordinary listening levels...but then again, I don't use my speakers in a HT system.

I've a pair of Theos arriving on Monday, and intend to sample a Dennis Had Firebottle KT88 amp on the speakers mated with a Depth i sub.
 
I have ML Monolith III, with the new aluminium vapour deposited clear coating, similar to the Neolith. I drove the ESL section of them with DHT SE 805 massive monoblocks 50w each with very very good 4ohm output transformers. The autoformer did allow me to drive them better, but a good 100w S/S amp drove them far better and made me think again about amplification. Just as an experiment I used the autoformers on the S/S amp and the sound quality took a big hit.

Cheers George
 
For grins I test drove a pair of CLS IIz's with a simple 8 watt SET amp.

I can't imagine the Prima Luna not having sufficient power to drive a pair of far easier to drive Theos to ordinary listening levels...but then again, I don't use my speakers in a HT system.

I've a pair of Theos arriving on Monday, and intend to sample a Dennis Had Firebottle KT88 amp on the speakers mated with a Depth i sub.

Very nice. Please do report back after your listening session.
 
Very nice. Please do report back after your listening session.

These newer ML speakers are not nearly as power hungry to drive as some seem to think. I've owned a Prima Luna 35 watter that drove CLS's to more than adequate listening levels. 15 years ago the Plinius SA100's mated to ML's were all the rave. But at 200 wpc 4 ohm, Class A, was far more overhead than one needed to drive them sufficiently.

Besides, "tube power" ratings are misleading, for a 35 wpc tube amp will drive most speakers adequately. I'm talking 2 channel listening, not HT bomb blasts. Serious listening. Again, everyone listens differently, and as such has different needs.

I'm curious why one would feel the need to place anything into the audio chain between their amp and their speakers? But I'm old school.
 
I have ML Monolith III, with the new aluminium vapour deposited clear coating, similar to the Neolith. I drove the ESL section of them with DHT SE 805 massive monoblocks 50w each with very very good 4ohm output transformers. The autoformer did allow me to drive them better, but a good 100w S/S amp drove them far better and made me think again about amplification. Just as an experiment I used the autoformers on the S/S amp and the sound quality took a big hit.

Cheers George
This aluminum vapor u talk about does Marin Logan offer this on there other speaker or just the neoliths?
 
These newer ML speakers are not nearly as power hungry to drive as some seem to think. I've owned a Prima Luna 35 watter that drove CLS's to more than adequate listening levels. 15 years ago the Plinius SA100's mated to ML's were all the rave. But at 200 wpc 4 ohm, Class A, was far more overhead than one needed to drive them sufficiently.

Besides, "tube power" ratings are misleading, for a 35 wpc tube amp will drive most speakers adequately. I'm talking 2 channel listening, not HT bomb blasts. Serious listening. Again, everyone listens differently, and as such has different needs.

I'm curious why one would feel the need to place anything into the audio chain between their amp and their speakers? But I'm old school.

To make it sound even better than it already does... tweaks...
 
This aluminum vapor u talk about does Marin Logan offer this on there other speaker or just the neoliths?


Yes I believe it would to all models maybe, as Jim Powers sent me these about 4 years ago.
He said at the time they were the new aluminium vapour deposited ones that are very clear and see through.

Cheers George



I'm curious why one would feel the need to place anything into the audio chain between their amp and their speakers? But I'm old school.


Yes this a bit nutz, especially with a tube amp, why drive one output transformer into what is basically another output transformer (autoformer), dumb! Get it right to start with, either with speakers or amp.

Cheers George
 
I have dialogue premium 7 with Theos and had the pro 6's before. More than enough power and dont have clue what the op is posting or the state of his hearing?
 
Yes I believe it would to all models maybe, as Jim Powers sent me these about 4 years ago.
He said at the time they were the new aluminium vapour deposited ones that are very clear and see through.

Cheers George






Yes this a bit nutz, especially with a tube amp, why drive one output transformer into what is basically another output transformer (autoformer), dumb! Get it right to start with, either with speakers or amp.

Cheers George

I just posted a question out of curiosity and that is your response - dumb? Chill with the snobbery there bloke. I had just read about autoformers and heard that they worked great wonders with tube amps. No big deal.
 
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They are not cheap, that money is better served towards a purchase of the right poweramp to be able to drive the speaker or easier to drive speaker, it is an expensive band-aid fix.
And I meant generally the "IDEA" of it is dumb. I'm sorry if you thought I meant you.

Cheers George
 
Hey gang,

I did a search on here to see who may be using a set of Zero Box Autoformers in conjunction with Theos and a PrimaLuna Dialogue HP Integrated tube amplifier but couldn't find anything. Anybody try such a combination and can you tell me your results? Paul Speltz has a lot of testimonies on his AntiCables site as well as ZeroImpedance.com. One cat was using the Autoformers in conjunction with a tubed amplifier and ML CLS IIz Speakers.

I would appreciate any information at all from anybody with experience in having a set of Autoformers in their system.

Thanks! Dana


i used a set of Zero Autoformers for approx 2 years. My speakers are CLS IIz and I can assure you that the Autoformers are hugely musical and transparent. I lent them to a MAGAZINE REVIEWER at HIFI-CHOICE magazine. He also confirmed the great sound quality, however he noticed that they occasionally produced a SLIGHT LACK OF BASS CLARITY.
 
Homer,

To each his own.

My own is zeros.

I've had my prodigy for almost 10 years now. In the beginning I use some naked zeros and made a nice improvement in my system. As I continue to improve other portions of the system the zeros actually got in the way of maximum performance. So I sold them.

Eventually as I continued my upgrade march I just didn't feel I was getting out of system what it is capable of. So I bought another pair of zeros in the boxes. They produced exactly what I was looking for.

After that point as I continue to upgrade system components the zeros have always served well. When I take them out of the system it is less revealing and less involving.

They seldom come up used, but if you can grab a used pair you can try them for a while and see if that's what you need. They certainly have a myriad of possible ways to connect them.

Bruce

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A low power amp can drive the Theos nicely but it will start rolling off the frequencies above 10kHz and your high frequencies will be down maybe 10 dbs or more at 20kHz due to the .7 Ohm impedance of the MLs at 20kHz.

Frequencies above 10kHz are harmonics. According to a couple of charts I have, the only instruments that produce a fundamental above 5kHZ are piccolos and pipe organs. Synthesizers probably do too. The highest fundamental note a guitar produces is 1kHZ. You may not be able to hear above 10kHz anyway, depending on your age and how well you've taken care of your ears.

I drive my Ethos with a low power amp and they sound great but my Radio Shack Spl meter and Stereophile test record tell me that they are rolling off above 10kHz. I've been wanting to get an amp that doubles down down to 2 Ohms to compare with my current amp, but I haven't been able to do that yet.
 
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