What's wrong with the kiss, boy?

[Zen Mod]

I'm pretty sure I've got it sorted in head now. Just wanted to make sure of "second" wire in schematic wasnt something I missed.
........

for a moment , look at IDC connector and adequate flat cable

you have 14 pins and 14 wires there ...... while we are routing 6 different current paths with it ; how many second/double wires we have there?

you have one current path lead with 4 pins and 4 wires, and you have 5 current paths lead with 2 pins and 2 wires

that's called intentional redundancy

frankly, there is no need at all that one understands it all , just to wire bloody thing as written, and it'll work as intended

and it'll happen for sure, once when listening da muzak, it'll just click from nowhere "aha! I got it now!"

 

[ItsAllInMyHead]

" negative common for LEDs, all taken to switch"

Which, if you're a ham-fisted dodo like me... and short Rpos and Rneg... ooopsie daisy...

Of course, as mentioned... I didn't follow my own advise and FOLLOW THE SCHEMATIC when I was checking the relays. Not relevant to Russellc, but for anyone else with the current boards - take care.

 

[pfarrell]

ZM! good to know about lightshow and current boards. I'm missing the switcher schematic for current boards—!! Assuming it's in this thread somewhere.....

 

[ItsAllInMyHead]

It's in my post above where I bungled (for the Bal version). However, it should be the same for SE except only one set of pins going to the "Twister" b/c you only have to switch one set of relays on one board.

Edited to add - just in case.... here ya go. And of course... wait for ZM to confirm I am using correct schematic

 

[Zen Mod]

don't fret with latest boards and schematic (with light Show)

this is sorta first kitten thread and I believe there will be Build Thread, once when Iron Pre hit The Store

 

[Russellc]

Cool connector of joint forgivness[/URL]

Fair warning though that the tolerances on those is kinda wild. You may need to sand down the shaft a bit to make it fit. Not hard, just takes time and bit of sandpaper.

I sanded on my first kits shaft ends as shafts had a step in middle and each end was 2 different diameters. The couplers also had 2 different sized holes on each end. With different pot shaft sizes, different diameters of holes in knobs, sometimes you get left with a shaft that doesn't match up.

After the sanding fiasco, I learned to take the offending part, back out the Allen screws clamp in vice and drill it out.

Russellc

 

[Russellc]

Guys (not ZM)—would it help at all if I pointed out that the reason there are 2 rows of contacts in the switch zone is because the header blocks you can buy drop right into ZMs layout and fit ready made ribbon connectors that all have 2 x 14 contact points? I was making things very complicated in my noob mind trying to understand why there were 2 rows when it seemed I only needed 6 connections to make it all work.... (...until 6L6 fixed my brain....)

Also, I elected not to hook up a mute position. So I only have the common plus 5 wires running to the Lorlin switch. Common (pad "2" in my case) to "A" on the switch. then 1-5 on switch connected to 4,6,8,10,12 on Iron—No mute in my case—didn't see the point.

This makes it much simpler and is how DCG3 worked. With continuity buzzer hooked to either one of center pins, you can easily determine which half of pins to hook up to.

I build power amps with little trouble. Preamps, especially the switching, gives me fits for what ever reason, likely hardness factor of head.

Russellc

 

[ItsAllInMyHead]

Impressions

As anyone that's read any of my "impressions" knows - I am not a fan of providing subjective impressions b/c of the fever-pitched shouts that can result...

So, for all the caveats - see some of my previous posts. I don't want to type them again. However, this is a hobby that I love - so not providing impressions of how "I" feel about certain gear would be a bit of a bummer. Just remember, I'm deaf in one ear, and I can't hear from the other. Also, in all seriousness, ZM was so kind to allow me to be one of the first people to get my hands on this, so not offering an opinion would be in very poor taste, IMHO.

I like to try and remove any "audio memory" as much as possible if I know I'm going to intentionally switch gear. This was not intended to provide impressions of the Iron-Pre Balanced (IPb) against any other pre-amp. So, as mentioned previously, for about a week or more I listened to my DAC going straight to the Babel J2 using digital attenuation. BTW - that's a wonderful solution too. I wanted to know what adding the pre-amp would do; not compare it to other pre-amps (for now). My hobby, my fun...

After making sure the IPb was up and running properly (sans chassis) and allowing the BJ2 to warm back up, I played some tunes for a few hours last night. Nothing serious, just doing some work that I had put off while fixing my bungle.

Immediate impressions:
1) Dead silent. Nothing, nada, zip, zilch at speakers with volume all the way up. Now, is that necessary? Is it relevant? I don't know, but it was noticeable in it's utter silence between tracks also.

2) There was maybe some added "snap". So WTH does that mean? I think I felt that snares and plucked instruments had a bit more ooomph on attack. That bit of detail on initial strike that's different than the overall tone of the instrument. Hard to describe...

After a good night's sleep, I decided to sit in the sweet spot and listen a bit more carefully to completely different music. I listened to it with the volume pots cranked using digital attenuation for awhile. Then I went back to no digital attenuation and controlled the volume "normally" using the dual pots. Some people hate digital attenuation... some people think pots are bad or that some are better than others... that's not for this discussion. For those keeping score at home, I used these https://www.digikey.com/products/en?keywords=KKA2531S28 To my ears, there was no noticeable difference re: the method of attenuation other than taking care to try and get both channels the same when using the pots.

Mainly... since amplifiers behave differently at different output levels, I kinda wanted to see if pre-amps may behave somewhat similarly. Do they "clip"? My DAC puts out a purported 5V. So does attenuating the input help? These are impressions and questions from a music lover that is still learning electronics.

What else - nothing. Nada. It adds nor subtracts anything that I'd bet more than a dollar on. It's "transparent" to use an overused term. That's what I was looking for, so maybe some confirmation bias kicked in. Either way, I'm thrilled.

If anyone's looking for what (IMO) is a completely neutral / transparent pre-amp. This may be your ticket. Boards coming to a DIYAudio Store near you soon

Setup - Roon endpoint -> gizmo -> DAC (balanced / differential) -> IPb -> BJ2 -> Tekton DI. All analog connections over XLR.

As always a heartfelt thank you to the Mighty ZM.

 

[Zen Mod]

well...... I'm spoiled, ya all know that

for me personally, when I see resistive attenuator, that's it - weak link

same as you don't hear well made xover until you hear same setup with xover removed (if possible)...... once you hear proper setup without resistive attenuator, you'll know the difference

anyway, what you are hearing now, just confirmation that it's worth having decent shunt reg for decent buffer,which is driving decent xformer, everything situated on decent pcb

 

[ItsAllInMyHead]

well...... I'm spoiled, ya all know that

for me personally, when I see resistive attenuator, that's it - weak link

same as you don't hear well made xover until you hear same setup with xover removed (if possible)...... once you hear proper setup without resistive attenuator, you'll know the difference

anyway, what you are hearing now, just confirmation that it's worth having decent shunt reg for decent buffer,which is driving decent xformer, everything situated on decent pcb

Makes perfect sense. Two experiments (this is fun stuff for me)... coming sometime.

1. Pumpkin (of course) - I still need some sort of attenuation for non-streaming.

2) Bypass switch for pots - use digital attenuation so my lazy butt doesn't need to move for streaming. Then, flip switch to engage the input attenuation when needed.

Definitely #1. #2 maybe. Just an idea I was noodling.

"Decent" is an understatement.

 

[Zen Mod]

well.....illustration :

tube amp; Softone - damn!!! modern one, even using Toshiba Mosfets as main gain elements, automatic bias, first class parts, squeezing from toobz last ounce of life while still sounding good,no mythology attached, costs less than 1K in Japan

tube amp; write here any of exotica name;made with extra Kosher parts, schematic copied from Yore,sound deteriorating with time due to wakening of toobz,all mythology attached, costs 10-15K as normal thing

OK, I'm all for crafstmanship, even artistic valutation ....... but I hate mythology

proof is in da pudding, eat ya porridge and you'll be strong and big as your G'Pa.....

that's why decent ; we can do better, we know better, we can do overkill, we know overkill, we can go even insane ...... but first thing is that we never stop laughing at world around, including our self

so, Iron Pre is nice example of Horses for Courses - nice and funny and presumably not too expensive

and, major prerogative is that it must be better than Pa's B1T

 

[pfarrell]

well...... I'm spoiled, ya all know that

for me personally, when I see resistive attenuator, that's it - weak link

same as you don't hear well made xover until you hear same setup with xover removed (if possible)...... once you hear proper setup without resistive attenuator, you'll know the difference

anyway, what you are hearing now, just confirmation that it's worth having decent shunt reg for decent buffer,which is driving decent xformer, everything situated on decent pcb

ZM, what should we get to try in attenuator land? Assume cost effectiveness is a factor, but worth it for the education.

Also @P Anderson: I love reading your impressions of this stuff we build. Don’t stop!

And yes “decent” = Big understatement!

 

[Russellc]

ZM, what should we get to try in attenuator land? Assume cost effectiveness is a factor, but worth it for the education.

Also @P Anderson: I love reading your impressions of this stuff we build. Don’t stop!

And yes “decent” = Big understatement!

Well Iron Turtle of course. The promised land here is the autoformer, which can serve as transformer as Jenson, cinemag or Edcor does here, as well as having enough taps to be volume control as well.

Cheap way out? well not that cheap but AVC autoformer:

intact audio

200.00 the pair for least expensive version. Rather than scoot up in cost, I would go full on Iron Turtle.

Russellc

 

[Zen Mod]

ZM, what should we get to try in attenuator land? Assume cost effectiveness is a factor, but worth it for the education.

Also @P Anderson: I love reading your impressions of this stuff we build. Don’t stop!

And yes “decent” = Big understatement!

buy any decent 2x100Klin (either Alps or lucky Alps clone or some of those AllIsInMyHead linked to) , shunt wiper to gnd with 33K metalfilm and you're there

or- to really move forward,as Russell pointed (which I pointed earlier in the thread) - buy cheapest possible but!! decent AVC (which is Dave's pair for 200 bucks), but with any other switch other than those cheap blue-white from fleabay) , combine it with Iron Pre electronics and Voila!

same tricks for desired gain, if needed, as described in Iron Turtle threads - choose feeding tap and everything above is your gain

edit: I have in boxes some resistive attenuators costlier than these 200$ - Penny & Giles, TKD etc. ; I'm putting them in small boxes with few RCA and selector switch - they're handy to have in workshop and to lend them to boyz when needed, especially to enable them to hear how shitttttty are their preamps....... being nothing else than much inferior pot additionally choked with drekload of bad electronics

 

[ItsAllInMyHead]

Thanks for the kind words, PF. Now, I wanna hear what Russellc thinks.

I've also been trying to learn a bit about how some of the other approaches may work. I absolutely love learning about the different "stages" or chunks and what makes certain gear tick.

I've been looking at relay-stepped attenuation and muses. I have some relay-stepped boards that were used in another project (not built by me) that I'd love to try and re-purpose into one of my projects They're "quad gang" if that's the right term for 4 channels in a relay-stepped system. I just need to learn how to measure them and figure out the pin-outs. Then, hopefully, I can give them a try.

I also have some of the Hans Polak relay-stepped boards from a group buy and a muses solution heading my way. Both are a bit over my head for the moment, but soon...

I'll definitely try the motorized 4-gang Alps I have on the way. That solves the "getting my lazy butt of the couch" problem. I'll definitely be hitting up pfarrell for some tips on how to put a remote with it.

And of course... Turtle.

 

[Russellc]

Thanks for the kind words, PF. Now, I wanna hear what Russellc thinks.

I've also been trying to learn a bit about how some of the other approaches may work. I absolutely love learning about the different "stages" or chunks and what makes certain gear tick.

I've been looking at relay-stepped attenuation and muses. I have some relay-stepped boards that were used in another project (not built by me) that I'd love to try and re-purpose into one of my projects They're "quad gang" if that's the right term for 4 channels in a relay-stepped system. I just need to learn how to measure them and figure out the pin-outs. Then, hopefully, I can give them a try.

I also have some of the Hans Polak relay-stepped boards from a group buy and a muses solution heading my way. Both are a bit over my head for the moment, but soon...

I'll definitely try the motorized 4-gang Alps I have on the way. That solves the "getting my lazy butt of the couch" problem. I'll definitely be hitting up pfarrell for some tips on how to put a remote with it.

And of course... Turtle.

I've always used the ladder pots off ebay. I've wondered about the muse, but dont really know and havent heard one. I think zenmod has something similar/same in signature, blog or somewhere. But if he has been there and this autoformer has his eye, I'm figuring this is best way.

I see a balanced Iron Turtle in both of our futures is short story. But for now this thing is very good sounding to demonstrate principal that "more iron, more better.

Oh, and I wired the one channel to selector pot, see pic

Russellc

 

[Russellc]

Think I have pic posting problem beaten too! Good day!

Russellc

 

[Dennis Hui]

On the subject of "more iron, more better", has anyone tried the IronPre
with an amp with an input transformer (say F6, M2, SissySIT, SIT3, etc)?

Dennis

 

[ItsAllInMyHead]

Think I have pic posting problem beaten too! Good day!

Russellc

Looking gooooooood! I somehow envisioned the natural wood of the pizza paddle on the front

I have to just get over myself and prepare for drillin' some holes, and what will be will be. Trying to do the layout now in anticipation of the chassis being here by the weekend. Now... about that hole mover?

 

[ItsAllInMyHead]

On the subject of "more iron, more better", has anyone tried the IronPre
with an amp with an input transformer (say F6, M2, SissySIT, SIT3, etc)?

Dennis

Pick me!

Iron Pre with SissySIT is pretty fabulous, IMHO.