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Bruno Putzeys Balanced Preamp - Group Buy Part 2

Do you have one more bare board, please?

This Group Buy for the assembled PCB is now full.

I am processing a waiting list on a first come / first served basis. If you want to join in, please email me (see below) to register interest in case anyone drops out :) Please note I would like to limit those on the waiting list to one bare PCB, one assembled PCB, one pair of Hypex regulators at most so it's fair for others further down the waiting list.

Update 23rd March: PCBs received :)

This is a follow-on thread from the one Bertel / Robert started for Bruno Putzy's Pre-amp design, here. I (tfboy / Xavier) have taken over the GB duty from Robert and managing this going forward. :)

The pricing below is based on an order of 100 assembled PCBs. We have sufficient numbers from the original shared Excel sheet to go ahead with the group buy :)

Please keep this thread strictly for the GB / ordering process. The discussion of the design can be done in the original thread here

The board comes in two flavours:
  • A bare PCB
  • A semi-assembled PCB with all SMD components and the four high-current Melfs soldered on. All PTH components (Caps, XLR sockets, JST connectors, volume pot, etc) are excluded. You'll have to source these components yourselves and solder them on, but that should be an easy job for the novice.
Independently from the bare PCB or SMD-assembled PCB, you can opt for the Hypex HPR / HNR regulator option. PDF datasheet is here. These are Hypex's own high-precision regulators. You do NOT need to have these: they can be substituted for normal TO220 regulators. Please note, these are supplied in pairs. So when you say a quantity of "1" means you will get one HPR and one HNR. Hypex regs will be supplied unsoldered to the board. This is just an idea to get a group discount (around 30%).

If you don't take the Hypex regulators, youll have to add a pair of regular 12V (L7812+L7912...) regulators to your PTH parts list.

The boards and assembly are being done by Quick Circuits, a local company where I live in the UK. Board spec is 1.6mm FR4 RoHS compliant dual layer board in ENIG finish with green mask and white silkscreen.


Pricing (in GBP):
  • Bare PCB: £3.50+VAT = £4.20
  • SMD-assembled PCB: £27+VAT = £32.40
  • Optional Hypex regulator pair: £16.50+VAT = £19.80 per pair
  • Packaging cost: £2

All assembled boards will be shipped in antistatic bags, wrapped in antistatic bubble wrap, packaged inside a cardboard box :)

Shipping is in addition: I'll be able to give you a cost once I know the shipping address (see below).
Assuming one assembled PCB, approx costs are:
  • UK destination: £4.40 (1st class signed for) / £7.25 (RMSD)
  • EU destination: £10.15 (Royal Mail International Tracked & Signed)
  • USA destination: £12.45 (Royal Mail International Tracked & Signed)
  • Rest of world: £12.45 (Royal Mail International Signed)

For those outside the EU, I'll also print the invoice and affix it to the packaging in one of those transparent "Documents Enclosed" envlopes to reduce any potential issues with Customs.

Tax / VAT explanation

We're dealing with a professional business so they are charging VAT. To try and save money to some of you lucky non-EU people, I'll buy this through my business (Xav Broadcast) which is also VAT registered. What this means is:
  • For those of you living in the UK, you will have to pay the VAT. If you're VAT registered, you can recoup this in your next VAT return (I'll provide a VAT invoice).
  • For those of you living outside the UK but within the EU, you will have to pay the VAT unless you can provide me with your EU Tax code.
  • For those of you living outside the EU, you're lucky, and are exempt from paying VAT. I do not know whether you'll have to pay import duty though, and that's your responsibility. For postal insurance and export purposes, the value has to be declared.


Payment

Preferred method: Wire transfer. I would highly recommend Transferwise.com I have used them a lot in the past when sending money abroad in euros or US dollars. They offer a very respectable exchange rate and minimal handling charges. You'll be able to specify the exact amount received in GBP.

Alternatively, you can pay by bank transfer, but this will likely be more expensive than using Transferwise unless you already have an account in GBP.

If you have a UK bank account, a normal transfer is of course the easiest option.

There are a few countried where Transferwise isn't an option at the moment. For those countries, I can arrange a Paypal transfer but would far prefer a bank transfer.

update 6th March 2016:
Over the next few days, I'll start emailing out pro-forma invoices by email. You'll also receive payment details: my UK bank account number and sort code along with IBAN and BIC codes for international transfers.

When you make payment, it is imperative you put your forum username as the reference so I know who has paid.
When using Transferwise, you get the option to provide a reference at step 4:
i-HxdzkQ8.png


If you haven't yet used Transferwise, you can use my referral code to get a free transfer: https://transferwise.com/u/909e12

Once I receive your payment, I'll package up your order and deliver it. You'll then receive by email a tracking number and full invoice (which replaces the pro-forma). A copy will be attached to outside packaging for customs for those of you outside the EU.

I would really like to avoid Paypal if at all possible. If you have to use Paypal, please use the Send money to friends and family option and not the Pay for goods or services. Apologies, I had written Paypal Gift in the email sent out; they've changed this to the friends and family title instead:

i-dcKLPNf-L.png


If you use the one on the left, Paypal take a fee from what you send and I'm left short.


Ordering process

I'll drop using the Excel sheet originally created by Robert: I've set up an email address for the GP. Please send an email to HypexPreampGB -at- xavbroadcast.co.uk (replace the "<space>-at-<space>" with "@") and use the following template:



I've now PMed all those who initially responded to the GB and who read my PM when I took over. I'm aiming to close this GB by Sunday 6th March - I hope to be near the 100 quantities by then. I've decided to do this so that those who've been waiting for some time don't have to wait much longer; it's been going on for some time since Robert started it back in September last year :)

I hope that's all clear. Any questions, just ask :)

A few photos:
Bare board:
i-wTH22SQ-X3.jpg

i-F2SzrTF-X3.jpg


Assembled board:
i-Cjh4t67-X3.jpg

Hi, do you have one more bare board to sell, please? If yes, please send me a PM and we'll discuss the details. Thanks!
 
Hello,

I'd like to purchase the BPPBP -- board or complete, if anyone is selling this. Thanks.

Hi, I could sell to you my Bruno's Preamp if you want it, ready to listen. It was made at the end of the last year using the best components - very professional made board who worked from the first time after soldering the components on it, low noise SMD resistors ( as Bruno specified in the article), Nichicon Caps, NeutriK XLR (golden pins) sockets, Hypex low noise dual Regulators, R-Core transformer for the P.S. with the 115V voltage option for the U.S.A. ( I think, I'll check if you want it) and the Hans Polak Volume Controller 16 steps with Dale resistors.
https://linearaudio.net/sites/linearaudio.net/files/hp bruno potmeter 3.pdf The only modification to the original schematic - I've changed the Dual TL072 OP with the modern and better low noise ( with the JFet inputs like the original TLs) OPA 2134.
It has an black aluminium compact case, aprox. 8''W * 3.2''H * 4''D.
It sounds as it should, totally transparent like Bruno said. The only drawback of this Pre is that the 16 steps of the Volume Controller are not linear, step by step. When you turn the Volume up for one step, you will hear a slightly lower volume sound... then at the next step you will hear the louder step so on and on until the loudest volume, meaning that you will have 8 volume steps instead of 16. I don't know why it's that, I've checked the Hans circuit, the wires connection to the rotary encoder...but I got used with this, there is no noise on each of the steps. Maybe if you buy it and have the skills, you will find the issue or, better, ask Hans about that, it didn't bother me because I didn't change the volume often.
I sell it because I don't really need it anymore, I've had two sources for the inputs but now I have only one and I use the HQ Player program for music into the Computer with it's Volume, it's more practical to me.
The price will be $ 200 including shipping to U.S.A. I'm not at home for this period of time, I live in other town so if you want it I'll go home, make some inside and outside pictures and take it with me, packed well for the shipping to you. Any other questions, glad to answer.
Regards,
Horia.