They are actually the Peerless India W8-12t 12p that came up for buyout at Parts Express not long after Pa released his original SLOB article. I think he bought a bunch himself at the time.@chromenuts; I assume the bass units are SLOBs ? Which woofers are you using?
Convenient in that they wire up series/parallel to 8 Ohms.
I’ve struggled with output and extension due to the restricted baffle size I chose to go with when I originally built them.
I recently added some wings on the back and things improved a bit. I may push that concept a bit further if I have the time/motivation…so many projects.
I was considering changing them out to something with more xmax and a stronger motor from GRS.
It isn’t just cut and paste…the chambers are just barely big enough for the Peerless and they seem to have a smaller frame than most of what I find that would be an improvement in those areas.
This is a picture of my happy thumb

Things went as expected.
I was able to unzip the files without any issues.
Navigation was different on my version of the IDE…no button I could find to select module.
Eventually, I found how to select the module under the “Tools” tab.
Afterwards, I couldn’t select a port as none were available.
After staring at screen for a while I tried shutting Arduino down and relaunching it.
Then I explored devices on the computer. I only saw an unknown USB device with no port assigned.
Took a guess and stole another cable from my son’s room to try…Viola!
It went pretty smoothly from there.
I think this about uses up my luck with computers for 2025 😢😉
btw. take care that Monster Power thingie is not spritzing heavy magnetic flak
Turtle doesn't like brutes in vicinity, black silence is spoiled
Turtle doesn't like brutes in vicinity, black silence is spoiled
I was worried about that…but I have dead silence with no program playing.
Even at max volume I have to stick my head completely in the horns to hear anything.
If I hear anything it’s the faint hum of one of my amps because it has cycled the cooling fan on.
The Modushop steel cases do their job well 👍
Even at max volume I have to stick my head completely in the horns to hear anything.
If I hear anything it’s the faint hum of one of my amps because it has cycled the cooling fan on.
The Modushop steel cases do their job well 👍
but I have dead silence

did you observe burning-in of those copper foil signal caps?

Wow, it looks just gorgeous 😍 very well done, and of course welcome to the Club!👍It’s all good amigo.
To be honest, overcoming the hurdles is what makes the project more satisfying in the end…plus it allows me to be creative👍…that has kind of always been my goal in this hobby. I like to make pretty things that make pretty sound.
Sometimes it can be very frustrating when you feel like you made a lot of stupid mistakes…but hopefully you learn from them a little and make fewer mistakes next time!
So now I’m at that point where I get to sit back and contemplate all the blood, sweat and tears that went into this project and enjoy the fruits of my labor.
This baby has been a LONG time coming for me.
Hell…I ordered the original Pumpkin boards from you back before we ran into each other out at BAF 2019!
So I guess it’s time for some more gratuitous porn…
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What is my first impression?
In a word…nothing.
There is nothing in my way.
The combination of the Iron Pumpkin/Turtle and the Babelfish J2 in this system is ruthless. It just plain exposes everything in the recording.
It’s not harsh, it’s not warm…it is just plain veracity.
Excuse me…I have to wipe some of Coltrane’s spit off my face…
...and your speakers... they look crazy good... I'm deeply impressed

So after a few days in the basement system I want to confirm my suspicions of what I am hearing by taking the preamp on tour…
First stop would be the “main” system upstairs.
I want to hear what happens with the analog rig and also the difference I might note playing through the old KEF 104/2 I have been using temporarily there.
One issue I immediately notice is that I have no ground lug on the Iron Pumpkin to connect the phono ground to.
Do I just add a grounding lug to the back of the Pumpkin and tie it into the star ground in the baseplate?
First stop would be the “main” system upstairs.
I want to hear what happens with the analog rig and also the difference I might note playing through the old KEF 104/2 I have been using temporarily there.
One issue I immediately notice is that I have no ground lug on the Iron Pumpkin to connect the phono ground to.
Do I just add a grounding lug to the back of the Pumpkin and tie it into the star ground in the baseplate?
Do I just add a grounding lug to the back of the Pumpkin and tie it into the star ground in the baseplate?
pretty much yeah, considering that audio GND of each Iron

Well, I promised wifey I would work on setting up and organizing a small recreation room for her after I finished building my Iron Pumpkin. The room is on pause until some other items arrive, so I snuck into the workshop.
I tried to do this the fastest and easiest way I could think of without defacing my beautiful custom casework.
I realized that the PEM has a shell and it’s grounding lug is welded to it during manufacture and I had already soldered my ground strap to that lug and bolted it to my star ground. Not gonna ground any better than that I thought.
So I carefully opened up the top mounting hole of the PEM and fitted up some slightly larger and pretty hardware I had on hand for a grounding lug.
Tah dah!
Oh…and I managed to sneak an audio related project into the recreation room 😉
All I need to do is put together my ACP+ kit to use as a preamp with the ACAs.
Didn’t want you to think my priorities were getting completely out of whack
I tried to do this the fastest and easiest way I could think of without defacing my beautiful custom casework.
I realized that the PEM has a shell and it’s grounding lug is welded to it during manufacture and I had already soldered my ground strap to that lug and bolted it to my star ground. Not gonna ground any better than that I thought.
So I carefully opened up the top mounting hole of the PEM and fitted up some slightly larger and pretty hardware I had on hand for a grounding lug.
Tah dah!
Oh…and I managed to sneak an audio related project into the recreation room 😉
All I need to do is put together my ACP+ kit to use as a preamp with the ACAs.
Didn’t want you to think my priorities were getting completely out of whack

The Iron Pumpkin finally found its way upstairs this morning.
Here you can see it playing very nicely with my pair of SONY VFET Part 1 amps (I adopted a second one in the swap meet recently). I’m bi-amping the high and low sections on the KEFs with them.
If you look close enough you can see I have the Pumpkin set to “Maximum Zen”! This brings me to an acceptable and yet politically correct level…depending on whether wifey is home and working 😉
I suspect Pa might be proud that I am using every last bit of my volume control
I probably should up the gain setting on the Pumpkin so I have more to play with for “enthusiastic” listening. I don’t remember if that has an affect or distortion and etc. It’s currently set at 2dB.
I don’t know why this combination would be so right, but it is very enjoyable.
I doubt the old KEFs are optimal with their 4Ohm load and 92dB rating…not to mention they most likely have tired crossovers and tweeters that should have the ferrofluid serviced.
However, the VFETs sound fantastic with them.
Bringing in the Iron Pumpkin has injected some desirable clarity back into the system as compared to the Doge 8 tube preamp I was playing with in this system. The sound stage has opened up as well. The system has a very balanced and relaxing feel without sacrificing detail.
This system has accidently evolved into a dedicated analog system…at least temporarily. I don’t have a cable that can plug into my MacBook Pro and also work with the distance between the channel jacks on the back of the Pumpkin.
Here you can see it playing very nicely with my pair of SONY VFET Part 1 amps (I adopted a second one in the swap meet recently). I’m bi-amping the high and low sections on the KEFs with them.
If you look close enough you can see I have the Pumpkin set to “Maximum Zen”! This brings me to an acceptable and yet politically correct level…depending on whether wifey is home and working 😉
I suspect Pa might be proud that I am using every last bit of my volume control

I probably should up the gain setting on the Pumpkin so I have more to play with for “enthusiastic” listening. I don’t remember if that has an affect or distortion and etc. It’s currently set at 2dB.
I don’t know why this combination would be so right, but it is very enjoyable.
I doubt the old KEFs are optimal with their 4Ohm load and 92dB rating…not to mention they most likely have tired crossovers and tweeters that should have the ferrofluid serviced.
However, the VFETs sound fantastic with them.
Bringing in the Iron Pumpkin has injected some desirable clarity back into the system as compared to the Doge 8 tube preamp I was playing with in this system. The sound stage has opened up as well. The system has a very balanced and relaxing feel without sacrificing detail.
This system has accidently evolved into a dedicated analog system…at least temporarily. I don’t have a cable that can plug into my MacBook Pro and also work with the distance between the channel jacks on the back of the Pumpkin.
I don’t know why this combination would be so right, but it is very enjoyable.
with Iron Pumpkin, everything is enjoyable

though, in this setup, VFet amps are weak link; KEFs are asking for more grunt
besides, we all know what Jewel exact VFet amps are, but in reality, they're evidently subpar to Iron Pumpkin**** .... speaking of dynamics and microdynamics (thus details etc)
If having that squeezed to max. isn't you intention, then OK
**** primary project premises of VFet amps and IP not at all the same
Unfortunately, this is not something I’m likely to grasp…even in re-reading VFET part 1 article by Pa and thinking about discussion thread of the IP I have read so much of.**** primary project premises of VFet amps and IP not at all the same
I remember Pa commenting on VFET performance into 8 Ohm and 4 Ohm loads…on the abilities of preamps used with them to reach full output…harmonic profile etc.
The VFET should work better with more drive from a preamp to reach the rated output and a more efficient driver with an easier load is more desirable?
Still IP has cajones no?…and even though KEFs are 4 Ohm they are not a slouch rated at 92dB.
I’m often in a situation where I simply try things together because I don’t know any better…and it’s what I have…you have to learn somehow right?
I’ve read for years that the KEFs need more juice (I had a Counterpoint SA20 that was a dream with them) but it doesn’t prevent me from trying and enjoying less powerful amps with them.
It’s sort of like being a kid in a candy shop…have you tried this flavor?
But I’m interested to learn why things do or don’t work well together.
The basement system had gobs of detail for sure…but after a few days I experienced fatigue with the front horns that I hadn’t previously. Miles and John’s horns were grating on me. Maybe it was the combination of the IP and the BJ2 amps with those speakers?
What is the root difference in the development premise between the IP and VFET and their intended use then?
I'm just saying - as much we love these VFet amps, I believe you have better amps at home, both better suited for KEF (dynamics) and more resolute (details).
Try it by yourself, then make your own conclusions, mine is just to give opinion
VFet is, by my experience, wakoo thingie perfect to shine in some ultraspecial system, comprised of decent FR or something like that, where each component in system is peculiar and quirky in own way
...even shorter - IP is ultra-analytic, while VFet amp isn't
Try it by yourself, then make your own conclusions, mine is just to give opinion
VFet is, by my experience, wakoo thingie perfect to shine in some ultraspecial system, comprised of decent FR or something like that, where each component in system is peculiar and quirky in own way
...even shorter - IP is ultra-analytic, while VFet amp isn't
What is the root difference in the development premise between the IP and VFET and their intended use then?
VFet amp - technically - quirky but still made with one eye on wallet; uberexclusive by circumstances
IP - technically - no holds barred, not really having an eye on wallet
if Pa did go same route with VFet amp, probably 60% of guys wouldn't end up with one, due to price
Maybe it was the combination of the IP and the BJ2 amps with those speakers?
most likely; you probably need more sugar than you're getting with that combo
say that IP + SissySIT is match made in heaven, for speakers with tendency to drill your brain if all puzzles aren't in place
though, maybe you just need piece of felt in right place, or decreasing highs a bit; it's yours to investigate ......
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