Pass Aleph P 1.7 preamp builders thread

[Erlend Sæterdal]

Finished boards eBay.

Think they are looking good.

2pcs Pass ALEPH-P(rev 1.7) Full balance Hife fever Pre-amplifier finished Board | eBay

 

[Erlend Sæterdal]

1.7 pcb

PASS 1.7 Hifi Preamplifier PCB / Balance Preamp PCB | eBay

 

[scipio13031965]

Thanks very kind

 

[wilu2]

Hello,

I am looking for a preamplifier for my Aleph 5. The choice fell on the Aleph P 1.7.
PCBs are hard to buy these days. I only found this:

Aleph P1.7 Preamplifier - HiFiStor

Does anyone have experience with this ?

Regards.

 

[Zen Mod]

Hardly that he's having permission to make them and sell them

 

[mrjayviper]

has anyone build this? if yes, where can I get the software for the volume control? thanks

 

[Mark Allen]

Ive begun the process of crafting a preamp following the fine design of the pass aleph p. the idea of building m own stereo was never something id ever considered possible except in my dreams. Thanks to this community and the generosity of nelson pass, ive been able to slowly learn bits and pieces about audio component design structure and function.

After finishing the pass labs pearl 2, designed by wayne at pass labs, and falling head over heels in love with records, i couldn't help but want to build a matching preamp/control deck to pair with it and my turntable.

This forum is to discuss the challenges and success in building a copy of the aleph p for personal enjoyment and education.

I've built two of them. One for myself and one for a friend. I'm not a big fan of remotes, so I used an inexpensive attenuator kit from an outfit in.Colorado whose name escapes me. The sound is phenominal and the attenuator switches have held up fine, even though they appear to be rather inexpensive. There are two input gain switches and a master, all stepped. I also try to avoid anything Chinese. If I were to build another I'd create a file of the boards I used and have more made, they were designed by one of our DIYer's and are more compact than the Chinese boards.

 

[mrjayviper]

they were designed by one of our DIYer's and are more compact than the Chinese boards.

Hi mark, can you please share the link to this compact design? Thanks

 

[Mark Allen]

Hi mark, can you please share the link to this compact design? Thanks

That was at least 6 years ago. So it would take hours to find on this site. But this afternoon I will post some images of the units I built, that will give you an idea of the differences. There may even be the name of the designer on the board.

 

[mrjayviper]

Thanks mark

 

[blackdod]

I built one a couple of years ago with components purchased from Mouser and it sounds pretty good.

Remember that you will have to add a resistor in parallel to the input Zeners (it is not on the board). Check the Papa Pass article 😉

 

[mrjayviper]

Remember that you will have to add a resistor in parallel to the input Zeners. Check the Papa Pass article 😉

Link?

What 10uF film caps did you use? Thank you

 

[blackdod]

Search in Papa Pass web 😉

Nothing esoteric... Nichicon Muse UES series.

 

[Danger Mouse]

Hi mark, can you please share the link to this compact design? Thanks

Maybe this one? PCB Dimensions 160x100
https://www.diyaudio.com/community/threads/pictures-of-your-diy-pass-amplifier.166784/post-3451377

 

[Thunders1988]

Hi, I’m starting the AP1.7 this week. Got the case and components coming in soon, only need to order the transformer. Having a custom one wound at Toroidy... Are the following specs OK or overkill?
1x 12v @ 0,5A (for the relay channelswitcher)
1x 60v @ 1.8A
1x 60v @ 1.8A
Using the purple boards off of eBay, by the Italian seller. Look good, so curious how it will turn out in combination with the Aleph J.

 

[blackdod]

I used (if i remember correctly) something like:
15v-0-15v @ 0.5 Amps
1X55V@ 0,7A
1X55V@ 0,7A

I think that you don´t need more but....

 

[Thunders1988]

Lay-out considerations... Keeping the inputswitch on the right kind of messes with my head. But it's the most logical given the circuitboard layouts.

We'll see. Couple of weeks waiting for the transformer... See if I can cobble something up to test the board already.

Another stupid question... Anyone experience with these kind of relay input boards? Can I, let's say, connect input 1 both the XLR and RCA in and use or XLR or RCA? Not both at the same time, but one or the other.
That way I don't have to keep drilling holes each time I buy/build another component.

 

[Thunders1988]

Pretty hectic weekend but got the thing running. Checked both channels but gotta keep it mono until the Toroidy gets in. Only had a 2x 35v transformer kicking around at 50VA. Not much but OK for testing, turned it down to 60 volts with a Variac.
Breadboarded a simple 12vdc supply for the relay PCB... Wasn't completely foolproof. Got the switch in the wrong way round. Have to fix it and tidy up the wiring. Pretty happy as is, no magic smoke or blowing fuses... All good. Least favourite thing still has to be done as well... Drilling the frontpanel. ;(

 

[Andy_D]

Hi,
Which type of Dale resistors you use?
Is no problem with heating for the transistors w/o heat sinks? Zener diodes 0,5 W or 1W?
Kr
Andreas

 

[Thunders1988]

Hi Andreas, can't detect any problems as of now. Have been using the preamp for a while now but will need to swap out the LED's for the channel indicators as they are too bright for my liking... Otherwise no complaints about this thing. Sounds great!