mwl168

Found the perfect length (8cm IIRC) screw at ACE Hardware. Got lucky! I screwed the bottom transformer down first with the supplied pads and washers and then stacked the second one on top. It's very secure. I laid out the components (PS, amp boards, transformers, XLR sockets) with the objective to keep the transformers and ac wires as far away as possible from the input wire and the amp boards. No buzz no hum that I can detect

Order placed with PCBnet. Will keep you posted with updates.

Here is a list of the participants and the number of sets (2 boards per set). Please correct me if I missed something. The * indicates that the participant has PayPal'ed me the cost for the boards. jose* 2 Kevin Gilmore 1 gwrskien* 2 PICaudio* 3 Sr Marques* 2 gepardcv* 2 MLA* 1 chinsettawaong* 1 chiguy* 1 MattN* 1 headinclouds 1 livewire 1 Inu* 1 GB will close after today. Tomorrow I will contact PCBnet to place order.

This is way cool Kerry!

Thanks Chris! Two 25VA transformers stacked - one for each channel

Old wine in a new bottle - just finished casing mySS Dynalo today. Dual mono setup - one Antek 25va transformer and one 20VDC GoldenReference for each channel. Just over 14mA current on each output device (MPSWx6). First built this SS Dynalo back in 2014. Every time I took a break from my ES setup to listen to this amp I am amazed how much I like its sound. Wish I had the chance to listen to the top Focal headphones with this amp...

My bad. I meant to close the GB in one week but I read the Calendar wrong. 2/26 it is. GB is reopened. I like to use heavier copper on PCB like the BH board with tube filament traces that carry higher current.

I don't have one on mine either although I do have a thermistor on the AC mains.

I can confirm that the 2 oz and 3 oz copper option is not a big factor in PCBnet pricing - in this case, it really comes down to the number of boards. It is also true that for other fab house (such as Seeed) the copper weight affects cost greatly. I don't know why. I can price out the GRHV boards at Seeed if people are interested. And yes, the PCB board is really a small % of investment compares to the parts and chassis, etc..

Why not follow the high-end audio industry practice and just use duck tape. They supposed to sound better that way!

Another two GRLV live! These are set up for 20VDC rails to power my dual-mono SS Dynalo. Thanks to Pars for his creation and generosity of sharing the Schottky bridges with a built-in AC snubber. Although I have to settle for the LM4040 VREF for now until I get the LT1021.

It does not look like we have enough interest in GRHV to support a GB. We will follow the original plan to close this GB today and I'll submit order Monday. Here is a list of the participants and the number of sets (2 boards per set). Please correct me if I missed something. The * indicates that the participant has PayPal'ed me the cost for the boards. jose* 2 Kevin Gilmore 1 gwrskien* 2 PICaudio* 3 Sr Marques* 2 gepardcv* 2 MLA* 1 chinsettawaong* 1 chiguy 1 MattN* 1

The BH board measures 5.6" x 4.5" (143mm x 115mm). The transistors are meant to be mounted off-board so if using an angle you'll need to add on to the 4.5"/115mm dimension. Like the Grounded Grid and T2, the tubes are meant to be mounted on the back side of the boards. Possibly a few others parts (LED, trimpots) too for ease of adjustment.

I have some Philip Miniwatt tubes.

Enkei is another option I can recommend for rotary forged wheels. I have a set of their 18" Raijin wheels and like them a lot. http://enkei.com/shop/tuning/raijin/ Enkei's been around for a long time and has manufactured wheels for Formula 1 cars.

Got the quote back for the PSU boards. 2mm thickness and 3 oz copper, at 10 sets each the dual board will cost about $37 US each and the split boards will be about $74 per set. I am not too surprised with the high cost, volume speaks.

Update: 1. MLA has gracefully volunteered to be the Europe "distributor" of this GB so I will ship all Europe-bound boards to MLA for him to relay to the individuals. thanks MLA! 2. Thanks to sbelyo for offering. I am happy to add the GRHV PS to the GB too. Please state your interest (number of boards, preference of split vs. dual boards) here. For these HV applications I recommend we use 2mm thick boards. I'll get a preliminary quotes from PCBnet and share the information here. We will likely need to extend the GB for a few days longer. Hope that's not a problem for you all.

All joking aside, no particular reason really. It's DIY and I like to tweak and experiment. 18V is well within the operational spec of the 2SK170/LSK389 and other associate parts. I happened to build a 18V GRLV for my SS Dynalo and decide to re-purpose it and build 20V GRLV for the SS Dynalo instead...

Are you interested in the dual version (B+/B-/Bias/LV all on one board) or the split version (B+/Bias on one board and B-/LV on a separate board)?

I run my BH with a GRHV set up for 400 VDC rails. The BH will draw more current than the Carbon does especially on the B- side. The BH ultra mini PSU will work too but the GRHV is more accurate, quite a bit lower noise and has much lower drop-out voltage. I use a 300VAC transformer with 325vac secondaries which handles the job well. I know there are others that run their BH with 450 VDC rails. If there is enough interest I am happy to add the GRHV boards to the GB but, depending on the number of boards ordered, the cost per board may be quite high.

I doubt it but maybe Kevin can confirm.

Just payment for boards now. I am working to see if someone will be willing to function as distributor for Europe participants so we can hopefully cut down the shipping cost for some.

I and a few others have decided to get the new bipolar version of Blue Hawaii PCB made by PCBnet in US. I used PCBnet for the Carbon GB in 2015 (and other occasions). Their price is higher but we’ve had great experience with their board quality. The boards will be 2mm thick and 4oz copper, green solder mask and white silkscreen in leaded finish. The cost of boards is $30 USD for a set (two PCBs) if we can get 15 sets made. You’ll need to add shipping from me to you for the total cost. Kevin released this latest version of Blue Hawaii in early 2016. I worked with Kevin to trace the board and at least one headcaser has built one working amp with them. This version uses all current production parts except for the 2SK170/LSK389 JFET which are still relatively easy to source. Here is a high level summary of changes from earlier versions of the Blue Hawaii: · KSA1220A/KSC2690A replaces the 2SK216/2SJ79 · 10M90S/DN2540 cascoded CCS replaces the A1968 based CCS · PZTA06 (smd) replaces 2SC1815 and 2SC2240, PZTA56 replaces 2SA970 · FQPF8N80C replaces 2SC3675 for the power supply of the third stage Please PM me or respond to this post here if you are interested. We are already close to meeting the 15 sets quota needed. I plan to close this GB on 8pm CST on Sunday 2/26 and submit the order to PCBnet on Monday 2/27. If you are ready to commit you can also PayPal me at the PayPal ID below. Please remember to include your HeadCase ID and shipping address (please don’t assume I have your shipping address - it’s buried in over one hundred entries in my PayPal account and not easy to find ). EDIT: The LSK389 is still in production just more difficult to source.

Replaced the mains fuse with a 4A slow blow and it survives the inrush current from the second power switch on the HV secondaries. Will try a 3.5A when I have them on hand. EDIT: replaced the 4A fuse with a 3.15A one and it's holding.