[Sarchi]

thanks.

[hagtech]

Probably December.

jh

[Sarchi]

Sounds good.  I looked through the forum discussions but not the blog posts, did you decide to configure it for low-Z or high?

[hagtech]

It has both low and high impedance outputs.  But only one volume control.

jh

[Theo]

It has both low and high impedance outputs.  But only one volume control.

jh

Jim,

Do you recommend that the HA-10 be used as a one input preamp?  I see that one can plug in two headphones to it.  Would it be advisable to use one output jack for headphone and the other for preamp out to a power amp?  Are the two outputs switchable so that the HA-10 can be used as a two input preamp?

Thanks.

[hagtech]

Yes, you can use both outputs at the same time.  When connecting Grados, there will be a few dB volume loss on the other output.  Something like a Sennheiser (or power amp) doesn't load down the circuit at all.  I have not tried the HA-10 as a linestage yet.  It would work, though.

I suppose if you wanted to, the "LO" impedance headphone jack can be wired as an input instead.  Two easy circuit trace cuts and some input re-wiring and you're in business.  This is possible as the phone jack I selected has built-in switching (not normally used), which would then select the RCAs if a plug was not inserted.  Such would give you two inputs and one output.

jh

[hagtech]

Ok, finished the design and ordered production boards today.  Should be here in about 3 weeks.  My proto here was done with black panels.  I now have to work on parts lists and assembly manual. 



Changed the default panels to natural aluminum color (silvery) with black lettering.  These files are available for downloading and you can modify as you wish, if you have the frontpanelexpress.com software.  Hey, engrave your own initials.  They make it very easy for you to order.  The panel pair will only set you back about $70, so I highly recommend it.  Makes the mechanical assembly way easier and the results are very professional.

Meanwhile, the specs came in.  SNR is 98dBA, bandwidth from 12Hz to 75kHz, output impedance 9 ohms, clipping at 3V input (4V output).  Here is the measured 10kHz step response.



jh

[Sarchi]

Nice!  Very nice.

I'll post up on head-fi about this.....uh, as soon as they come back online. 

[hagtech]

I can take pre-orders now.  Also posted final schematic online.

www.hagtech.com/images/castanetschem.jpg

jh

[ecramer]

Hello

Happy Thanksgiving


What's going to be the damage for the  kit?

I can take pre-orders now.  Also posted final schematic online.

www.hagtech.com/images/castanetschem.jpg

jh

[Theo]

Am curious to find out how much the stock parts cost, and order the parts.

[slwiser]

I noticed a comment about the design that someone elsewhere noted.  What is the correct view here?  Does anyone have any opinions?

"That is no way to do low impedance headphones, with one winding completely
unterminated. Needs to be wired with a switch that puts both secondaries in
parallel for low impedance phones."

I am clueless to this comments veracity.

[hagtech]

curious to find out how much the stock parts cost

Yeah, me too.  I really don't know yet.  Probably somewhere around $200?

Needs to be wired with a switch that puts both secondaries in parallel for low impedance phones

Hey, that would be great, if only there were two secondaries!  The 119DA has only one with two taps (autoformer style) of different ratios.  No possible way to wire in parallel. 

jh

[hagtech]

Holy moly!  The part cost came in much higher than I thought.  A primo DIY version will run exactly $500, sans any shipping costs.  It breaks down as:

Hagtech: $99 (blank board, wire, fuse, fuse clips, bumpers, washers, screws, L brackets, o-rings)
DigiKey: $69 (electronics)
Mouser: $61 (chassis)
Antique Electronics Supply: $171 (transformers, chokes, socket, jacks)
New Sensor: $36 (tube)
Front Panel Express: $64 (front and rear panels)

As you can see, all of the money goes straight into parts.  I net about $60 from this world-class design.  First draft of the parts lists are now available in a preliminary assembly manual online.

www.hagtech.com/pdf/castanet.pdf

jh

[hagtech]

Ok, added a preloaded DigiKey parts list.

http://sales.digikey.com/scripts/ru.dll?action=pb_view&pb_glue=1017081

jh

[poseidonsvoice]

Jim,

Do you have a picture of the board fully populated with parts? A nekkid photo like that on your website would be cool. Once you get the time of course 

Anand.

[hagtech]

Boards shipped yesterday.  I'll probably get them Monday.  And of course, I had to buy yet another set of electronics and trannys and chassis, which will get here Tuesday.  I'll take pics as board builds up.  The proto boards had no silkscreen or soldermask, so would not make for useful photos.  I like to write the manual just once.

jh

[hagtech]

Ok, CASTANET is finally shipping.  I got the first batch out today.  Then ran out of fuse clips.  Dang.  Will resume shipments on Monday.  Final assembly manual & photos & stuff now online.

www.hagtech.com/castanet.html

jh

[ecir38]

Sweet, preloaded parts list is a plus