Iron Pumpkin(s) and other smaller vegetable animals

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this thing lets more music flow. I have no way to describe it other than it's just 'more clear'. The bass is more prominent at low volume than I recall, and vocals are simply stunning along with guitar tones
Resistive attenuation places a blanket over the speakers. Inductive attenuation removes it. It's a "don't know watcha got till it's gone" kinda thing..
 
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Yes! You nailed it. I thought that I could pad down the input about 12 Db. When I did, that was exactly how it sounded. Now this isn't related to gain, but I was surprised to hear that much difference after the padding attempt. This also has happened on a power amp that 'refitted' with pots on the input. Gotta watch out with too much experimentation.
Sorry off track, I know.
 
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Twenty years ago I briefly had a high gain tube preamp paired up with a high gain SS amp. Of course the pre had a hair trigger volume control that was frustrating and annoying to use due to the poor mismatch. I liked a little "tube sound" though... easy solution, just put a voltage divider in front and knock the signal down.... it just killed the little bit of magic it had before doing that, ("enjoy your blanket sir.."). I was surprised and confused at the time. Another lesson learned, looking back on it now..
 
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Resistive attenuation places a blanket over the speakers. Inductive attenuation removes it. It's a "don't know watcha got till it's gone" kinda thing..
This seems to be particularly true (for me anyway) at those all important "don't wake wifey" levels of attenuation. Edited to add - volume is/was set at '6'. Haven't measured what level of attenuation that is. Still at 0dB gain.

I dunno... I just have to reiterate that it's awfully, awfully good.

For those that care... I went through Qobuz's "Summer of '73" playlist this morning. It's rare that the toes get tapping at such low listening levels. It's background music after all, and I'm trying to focus on other things. I'm wandering around the room and not even sitting near the sweet spot when I'm sitting. Yet... the music grabs me a bit more. It's almost distracting. Can't get my **** done. :rofl:

Edited again to add - Off topic... but now I'm VERY curious how this concept would work with headphones...
 
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^ Hmmmmmmmmmmmm... I thought when we discussed previously you said Pumpkin was no bueno for cans. I though you said that can amp needed to be a different type of beast. Shows what I know / remember. One of these days, I'll learn. :)

I may hit you up outside forum (unless you'd care to post) ... how a fella could add an XLR HP out jack (4 post) effectively / properly without totally ooking things up. 300 ohm cans primarily.

Edited to add - or... goofy concept... I can take two 3 pin and make my own cable... and just run from standard output...
 
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what I could tell, and will again - Iron Pumpkin wasn't exactly optimized for cans, but it still drives them surprisingly well

impedance transformation, while lower taps are chosen, is very nice thing ....

yeah, just make your own cable

though - remember - in case of having power amp unpowered while using cans - some input stages are sorta black hole, when not powered

meaning - it's best to pull amp signal cable

tedious, I know
 
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^ Noted with thanks. Drive from standard amp output and make a proper cable. I can make one for cans typically using 1/4" to SE outputs. I can make another for balanced 4-pin to to dual 3 pin.

Lower taps? Assuming that this means when using unity gain setting (0dB) and/or the lower taps are the higher attenuation ... I definitely won't need gain with cans.

Won't be done tomorrow, but ... on the list...

:worship:
 
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Now if only I could procure an IP!
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Chaps, sorry to be a pain..I've been reading as much as I can regards the Pumpkin, but I can't establish if the gain is active or passive? Is the gain simply from the windings of the autoformer, or is it from the buffer? There is a lot to read on this..

Also, is it possible to get a balanced output from the autoformer output on the SE Pumpkin? Very confused TBH

Many thanks

Dan
 
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100% passive voltage gain. For maximum performance, you want a circuit with a very low Rout in front of the autoformer. Exactly what the buffer provides. Buffer is "unity gain", no voltage gain, we just want / need the desirable impedance characteristics.
 
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