Amp Camp Pre+Headphone Amp - ACP+

You want the same form - the one from BOM will work very nicely. If you find an equivalent with solder logs instead of PCB pins that would be helpful.
The one from the BOM is right angle. I am looking for straight (and with solder lugs instead of pins, if possible).

NYS212 got solder lugs, but still Right angled... :(

This pdf document might be helpful

https://www.neutrik.com/media/8557/download/jacks---circuits.pdf?v=1

Or you could "buy insurance" to guard against making the wrong choice. It's easy and it's not incredibly expensive either. Just buy all three and see which one(s) are exactly what you were hoping for. The cost is pretty low and the benefit (peace of mind) might be pretty high, depending on your own personal tastes for risk, reward, cost, and waste.


_
You're right - not very expensive to just get all 3 and see what works... :)
Thanks for the 1-pager link. Very useful.
 
Member
Joined 2019
Paid Member
2SK2013 Q6

I finally got around to trying the Toshiba 2SK2013 in the Q6 position of my ACP. Sounds and measures really nice. The only adjustment I made was to lower R15 to around 700R. I haven't done any tweaking to R12/13, as it sounds really nice with 2R2/6R8.
 

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Hi. Did my own version of the ACP+ with integrated 24V PSU. It was designed to fit an existing chassis I have in stock. Unlike the original it has only one set of input, and no output. There is the option to use an external wallmart AC adapter, just don't mount the 24V supply parts. It also supports two models of volume pot, the larger ALPS Blue Velvet and the smaller (and much cheaper) RK097. I'll probably end up with a few extra pcb to sell. SB
 

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I took a 4 month break from DIY while having PLENTY of projects in a new house. I jumped online yesterday to see this ACP which looks VERY intriguing! A couple questions I have:

- I have two different matched pairs of J74 Toshiba JFETS. Can I use a different pair on each channel or do all 4 need to match?

- As for the wall wart Power, is it possible to use my wall wart from my Noir HPA? It's a .75A wart and not a .5A mentioned on Pass' page.

- Finally, is there a way to use a torroidal transformer with Jason Keutemann's Cap-Multiplier. I have been using boards from Rudi_Rozek on my Amp Camps with 24V with great results. Wondering if I could use one or maybe two on this amp. Not sure if I could use dual secondaries or if I would just use a transformer with a single secondary and a single board.

Thanks everyone in advance.
 
Last edited:
Official Court Jester
Joined 2003
Paid Member
I took a 4 month break from DIY while having PLENTY of projects in a new house. I jumped online yesterday to see this ACP which looks VERY intriguing! A couple questions I have:

- I have two different matched pairs of J74 Toshiba JFETS. Can I use a different pair on each channel or do all 4 need to match?

- As for the wall wart Power, is it possible to use my wall wart from my Noir HPA? It's a .75A wart and not a .5A mentioned on Pass' page.

- Finally, is there a way to use a torroidal transformer with Jason Keutemann's Cap-Multiplier. I have been using boards from Rudi_Rozek on my Amp Camps with 24V with great results. Wondering if I could use one or maybe two on this amp. Not sure if I could use dual secondaries or if I would just use a transformer with a single secondary and a single board.

Thanks everyone in advance.

- use them, preferably BL range

- more, the merrier

- link? I'm lazy
 
- Yes, both pairs are BL grade

- Good to know the wall wart will be fine

- I cannot find the link to the group buy but here is a schematic & picture of the board. With 20V secondaries I am able to dial in the board to give out 24V on the Amp Camp 1.6 board. I just do not know if two boards are possible to use on this ACP or if one would work just fine.
 

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Official Court Jester
Joined 2003
Paid Member
- Yes, both pairs are BL grade

- Good to know the wall wart will be fine

- I cannot find the link to the group buy but here is a schematic & picture of the board. With 20V secondaries I am able to dial in the board to give out 24V on the Amp Camp 1.6 board. I just do not know if two boards are possible to use on this ACP or if one would work just fine.

if you're going for regulated, with 24Vdc as target, use 24Vac secondary

that will cover all losses and cover possible mains fluctuation (-10%)
 
ACP+ BOM

Hi folks,

I've been working with 6L6 over the past month to put together a BOM for the ACP+ project with an eye on assembling a kit in the future from the BOM. Before we go ahead with that, we wanted to seek feedback from the community, so I am attaching an XLS version. Please look it over and let us know what you think.

Note that the file below had to be put on dropbox/share as the forum will not accept .xls files.

--Tom


Dropbox - ACP Plus Diyaudio BOM.xlsx - Simplify your life