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Ayre K-XR Pre and M-XR Monoblocks -- Who's heard them?

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Nelson Pass' (and why wouldn't it be) it uses active autoformers

what? you can't just make this stuff up as you go along...

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If the predator isn't different from the pico, and why should it be, then it's a great amp/dac combination with separate usb to i2s and i2s to analog stages.

Except that they're different, and it isn't.

Al, are getting new speakers for this rig? Not that there is anything wrong with the Gallos (I think that is what you have for your main speaker rig) but before I spent that kind of $$$$ on a preamp and amp, I would upgrade my speakers and go with a preamp/amp combo for less money.

Leave it to Grawk to turn a Ayre preamplifier thread into a Pico/Predator debate.

I did some digging, and the McCormack pre is completely different than the Firstwatt. The McCormack even has a +6 dB gain, which is really hardly passive at all. Next time I make an assumption labelled as such I'll be sure to use smilies.:rolleyes:

I wasn't, I was pointing out the "logic" of your comment.

And maybe next time, instead of labelling your assumptions with smileys, you'll refrain from making comments on gear based on false assumptions.

Jesus Christ, how many smilies do you need, Grawk?:eek::palm::rolleyes:

Leave it to Grawk to turn a Ayre preamplifier thread into a Pico/Predator debate.

I did some digging, and the McCormack pre is completely different than the Firstwatt. The McCormack even has a +6 dB gain, which is really hardly passive at all. Next time I make an assumption labelled as such I'll be sure to use smilies.:rolleyes:

yeah, not to mention the fact that:

A.) you made up the term active autoformer

B.) what the heck does "matching input and output impedances" mean anyways?

C.) What the heck do you mean about it's active then the rest is passive? What is the "rest" anyways, the output jacks?

Look, I didn't design it and I'm not professing that I could. These are direct quotes from Colin Pass. I have them written here in front of me. It appears the term "buffer" would have been more correct than "autoformer", but I hardly made it up.

If it's bullshit, I'll eat crow.

My understanding was that the only active portion of Pass' design was a buffer which was externally powered. It was used, in Colin's words, "to couple the input and output impedances". Clearly you've a more thorough knowledge of what this means than me.

I've clearly run afoul of the BS committee, so I'll keep my mouth shut on technical details from here on out. I respect the high S/N on this forum, and have intention of degrading it.

If Steve McCormack's design is anything like Nelson Pass' (and why wouldn't it be) it uses active autoformers to match input and output impedances, but the rest of the circuitry is passive. Firstwatt has that pre, and recently released a DIY kit with the JFETS for like $50.

Look, I didn't design it and I'm not professing that I could. These are direct quotes from Colin Pass. I have them written here in front of me. It appears the term "buffer" would have been more correct than "autoformer", but I hardly made it up.

If it's bullshit, I'll eat crow.

My understanding was that the only active portion of Pass' design was a buffer which was externally powered. It was used, in Colin's words, "to couple the input and output impedances". Clearly you've a more thorough knowledge of what this means than me.

I've clearly run afoul of the BS committee, so I'll keep my mouth shut on technical details from here on out. I respect the high S/N on this forum, and have intention of degrading it.

The bullshit is where you make up that one design is like another. Why even go there?

Why even go there?

out of pure ignorance. The idea of a hybrid preamp sparked my memory. I didn't entertain the idea that were a multitude of successful methods of implementing a hybrid preamp. After closer inspection, I was clearly mistaken.

Sherwood, how could you hold out on me if you heard the gear at RMAF?! Any more details other than "breathtaking"? :P

That seems like an invitation to participate to me.

I was clearly in error interjecting a technical explanation out of my depth, but it was an unrelated interjection. I don't feel it really degraded a thread about the KX-R.

And thanks for the snappy custom title ;D

yes, participate on things you know, not things you make up. "This sounds like that" great "this is the same design as that, so it is worth $50", when it's NOT the same design, not helpful.

If it's bullshit, I'll eat crow.

fine, I'll call you on it.

Sign up for an account at DIYAudio and post a question in the Pass Labs section addressed to Nelson whether or not this adequately describes his circuit and whether or not "active autoformer" is a real term and whether or not his circuit matches input impedance to output impedance. He will answer.

I don't have any problem believing that an active linestage can be less colored than a passive one. Passive electronics need to get their mojo from somewhere, and without the additional electrons, it seems to me they're MORE likely to be colored.

Not looking to getting involved in the other issues in this thread but passive line stages (eg Placette (passive), DacT) are resistors and switches. There is no mojo to add or remove. They have external power to power the switches etc but the signal path is entirely passive resistors. How would they ever add color to the system?

I guess they could if the system has cables so long and capacitive they need more driving to get the signal through, but then you have larger issues.

  • Author

Thanks for the input Sherwood.

The speakers will change, Mike, whether before or after anything else. I have thought about just getting a real preamp in the system before doing anything else -- amazingly enough the Voice of Reason actually suggested that -- so it is possible. Hell, maybe I should try the Ayre with the rest of my rig as it is now. :D

Sign up for an account at DIYAudio and post a question in the Pass Labs section addressed to Nelson whether or not this adequately describes his circuit and whether or not "active autoformer" is a real term and whether or not his circuit matches input impedance to output impedance. He will answer.

Since it's not my term, I'll decline your offer. I feel I've made a reasonable effort to be self effacing and admit to my mistake here.

As regards the B1 circuit, this description written by Nelson implies to me that it does match impedance.

I've no doubt he'll answer. I've enjoyed speaking with him before, though I don't currently have a DIYAudio account.

Seems that all of us forget from time to time that "I don't know" is a perfectly valid answer...

  • Author

Get over it guys, you made your point and Sherwood has eaten enough crow already.

Gallo should eventually release the giant reference towers. I don't know how they'll compare to the Ref. 3.1s, but if you like the 3.1 they're surely worth a listen if/when they come out.

Since it's not my term, I'll decline your offer. I feel I've made a reasonable effort to be self effacing and admit to my mistake here.

As regards the B1 circuit, this description written by Nelson implies to me that it does match impedance.

I've no doubt he'll answer. I've enjoyed speaking with him before, though I don't currently have a DIYAudio account.

funny, as Google shows no hits for the term "active autoformer". I think we can assume that you made it up.

Also, a buffer doesn't match impedance by definition. The article never says that it does.

Google shows no hits for the term "active autoformer". I think we can assume that you made it up.

I already mentioned where the term came from. I can't prove that I didn't make it up, though, so you're free to assert otherwise if you feel it necessary.

funny, as Google shows no hits for the term "active autoformer". I think we can assume that you made it up.

Also, a buffer doesn't match impedance by definition. The article never says that it does.

Please reread Voltron's post above. Sherwood has already apologized and said he won't repeat his mistake. So please, no more :horsey:

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