Aleph 30 Class A amplifier courtesy of Nelson Pass
I've created this page as a resource for any novice considering building an Aleph 30. Depending on where you live in the world can influence decisons on purchasing - a case for example might have taxes added/deducted and shipping costs can be a big factor (it's worth asking about surface shipping - slow but cheap). Trying to collect all the parts starts to give you some sympathy for those building nuclear subs! Try and order lots from one place to get free shipping and bear in mind lead times. Digikey, Mouser, Farnell
There is an excellent resource and community at DIYaudio (a lot of information here came from reading threads there) Aleph 30 Wiki
Excellent Chipamp v2.0 boards for Power, amp and
output (click on order and scroll down to the bottom)
Bill of materials for above in Excel and Adobe PDF
(updated and consolidated Nov 2011)
Schematic for above
Original Pass Labs Aleph 30 schematic
Original Pass Labs Aleph 30
owners/service manual
In addition to the Bill of materials you will need:
Multicore or Rosin solder (0.5-0.7mm)
16 x
Mica pads, thermal grease or silpads - these electrically isolate the
transistors
16 x M3 screw, nut, washer and insulating sleeve
Standoffs
an M3 tap and 2.5 drill for the heatsinks
IEC socket,
CL60 thermistors,
Slow blow 2A fuses
2 RCA female,
2 XLR 3 pin female for balanced ,
4 x speaker posts
Solder tags (3.2mm id worked with the terminal blocks)
Terminal blocks
Earth/ground terminals
Wire for amp internals
15W soldering iron (Weller and Antex are both good makes) with a chisel tip
Multimeter
and in the very useful category - a secondhand analogue oscilloscope. Dual trace or dual beam, >=20MHz
(e.g. My Tek 2235, 100MHz, dual trace, 2mV/cm), a digital infra red thermometer
Transformers
Rail voltage (assuming cap input filter) = transformer
secondary voltage x 1.414
e.g. 18Vac x 1.414 = 25.4Vdc but, the bridge rectifier steals a couple of
volts, so your actual rail will be more on the order of 23Vdc
Airlink
Amplimo - Netherlands 2 different qualities
Canterbury windings - UK Audio
grade designs
Toroidy - Poland Audio class
Some nice
transformer
cases
Cases (prices November 2011)
If supplied from EU
21% Tax will not apply outside EU, If USA supplied Import duty and VAT can apply outside USA
Aleph 30 dissipates 100w per channel so so heatsink requirement for 25C above ambient is 25/100 = 0.25C/W
| Make and model | Construction | Price | Tax in EU | Import duty | Shipping | Width | Depth | Height | Fin mm | C/W | ||
| Hifi2000 Pessante dissipante 4U | Italy | 4mm Al face, steel (10mm face +10 Euro) | 115 Euro | 21% | 25 Euro | 483 | 300 | 165 | 40 | 0.31 | ||
| Hifi2000 Pessante dissipante 5U | Italy | 4mm Al face, steel (10mm face +10 Euro) | 152 Euro | 21% | 25 Euro | 483 | 300 | 210 | 40 | 0.2 | ||
| Hifi2000 Pessante dissipante 5U | Italy | 10mm Al Face, 3mm Al rear, 3mm Al | 192 Euro | 21% | 25 Euro | 483 | 300 | 210 | 40 | 0.2 | ||
| THL PWAD-01 | Taiwan | 8mm Al face | £106 | 402 | 260 | 134 | Rear cutouts | |||||
| Design & build ezPower | NZ | 3mm Al Face, 2mm Al rear, steel | $225 | $106 | 432 | 300 | 150 | 0.33 (30C rise) | Pre punched rear, labels | |||
| Par Metal 22-17125B (ebay) | USA | 3mm Al Face, 2mm Al rear, 1.5mm Al | $165 | $33 | $85 | 425 | 290 | 130 | 50 | |||
| Fischer Elektronik SKE 5 400 | Germany | £334! | 400 | 315 | 215 | 40 | ||||||
| Lite Audio A200 3 sinks per side | HK | $189 | 480 | 430 | 150 | Rear cutouts (+XLR) | ||||||
| VTC AR-998B | HK | 7mm Al Face, Steel | $107 | 480 | 380 | 180 | 32 | Cutouts and connectors |
Audiokit sell the Hifi2000 cases
Building
After you have gone cross eyed ordering all the parts it's time to get started. I decided to build the power supply board first and fell at the first hurdle - I looked at the caps and could not see the polarity (no laughing this is for novices) - it's not like the markings on a battery! For those that don't know. For LED's Anode is the long leg, Cathode is the short leg, Anode is the Triangle side of a circuit diagram ,Cathode is the Flat line of a circuit diagram
My first attempt at soldering went OK but no more. Simple fact was that the iron wasn't hot enough - I had to put the iron on the pad/leg for too long and the solder did not flow well. Turned the heat up and it was much better though you have to be quickk
Original heatsink was 25mm tall and 12.7mm wide - can go up to 16mm wide on the board. Heatsink I used (Aavid SW63-2) which have unequal channels use the smaller one, there is also a vertical groove into which the thermal pads slide which provide electrical isolation. The best pads for thermal conductivity are Mica with grease and Silpads (look for a low thermal resistance)
Bleeder resistors are a safety measure, they drain off the charge after switching off. The PSU will work without these installed, just bear in mind that when you're gonna do some maintenance the capacitors still hold a charge.

Soldering PCB video for novicess and an excellent guide use a crocodile clip as a temporary heatsink
Torquing TO-220
Heatsink/Mounting TO-220 and
another and another
and another
Not an
Aleph 30 (an Aleph-X) but very useful
Guiseppe Bianco A30 (originally in Italian)