[BUILD] Hairball Audio - Elements

[terrydactyl]

I should mention I did check continuity and everything seems to be there.

-t

Resistors all match up. 

 

[Echo North]

What is the DC resistance (ohm tester) between one of the greens on your input transformer and each of the other leads?

Mike

 

[terrydactyl]

What is the DC resistance (ohm tester) between one of the greens on your input transformer and each of the other leads?

Mike

BRN:  9.5
R:  2 ... (fluctuates a little)
W:  9.5
BLK:  2
GRN:  0.4
V:  323
GRY:  167.8
Y:  168.4
O:  0.2

 

[terrydactyl]

BRN:  9.5
R:  2 ... (fluctuates a little)
W:  9.5
BLK:  2
GRN:  0.4
V:  323
GRY:  167.8
Y:  168.4
O:  0.2

I went back through the thread and read poster 'Darkus' had the exact same issue, same symptoms, and it turned out to be a bad input transformer...  Maybe? 

 

[Echo North]

I went back through the thread and read poster 'Darkus' had the exact same issue, same symptoms, and it turned out to be a bad input transformer...  Maybe?

Yes, you have a short in your primary.  Surprised you pass signal at all.

Email us: info(at)hairballaudio(dot)com

 

[terrydactyl]

Yes, you have a short in your primary.  Surprised you pass signal at all.

Email us: info(at)hairballaudio(dot)com

Emailed.  Thank you so much!! 

Can't wait to build the next one!! 

-Terry

 

[terrydactyl]

Emailed.  Thank you so much!! 

Can't wait to build the next one!! 

-Terry

Apollogies for not following up.  Put the new input transformer in and holy moly!!!  I was getting some signal before but now...NOW.... I've got some serious gain!  This thing sounds friggin AWESOME.  It actually sounds really, really good. I'm especially liking the DI on it.  Wow! Thank you!!  So stoked!!!! 

 

[lofi_beatsci]

Hi Mike -

I've got a silver build I'm piecing together. For C301, I've got a 100pF ceramic cap rated for 50V. I see the other cap in that series (c300) is rated for 63V. Do you think the 50V will be alright coming in off the DI?

Thanks in advance.

-Matt

 

[charlievela]

Hi.

I just completed a pair of Coppers. Channel 1 is working perfectly, on channel 2 I made a dumb mistake and flipped Q600 and 601 (which I know is highlighted in the build guide, but my distractibility knows no bounds)

At first it wasn't passing signal at all, once I desoldered and flipped the components, I got a signal that was occasionally interrupted by a clicking sound, that only got worse over the next few minutes. Now there's no output and a continuous clicking that's modulated by the buttons on the front panel. I'm assuming I fried one or both of the components when I desoldered. Is there a way to verify? I'm going to try and place a mouser order right now just in case. But I want to be sure I didn't mess anything else up.


Video of the noise: https://www.youtube.com/watch?v=S3I30AVvva8

 

[OwenAudio]

Hi!  Putting together my first gold preamp, and first build.  When populating my board today with resistors I got to R604-3R9 and R605-3R9.  The color code on the resistor matches my reference material but the reading I get from them when measuring with my multimeter is 4.5 ohms.  That’s way outside the stated tolerance.  Is it a bad resistor?  Do I go with it?

Thanks,
Nate

 

[TillM]

Use it, nothing will happen.

 

[OwenAudio]

Use it, nothing will happen.

I figured that, but just wanted to be sure.  Thanks!!

 

[Echo North]

Posting an email question here about transformers.

GA80071 (PM1000) as an input:

I'm working under the assumption this post is correct:

Here's how I understand it:

Brown -- Primary Center Tap
Green and Blue -- Primary Leads
Yellow and White -- Secondary Leads (I've seen yellow labeled "cold" and white labeled "hot.")

Black must be an internal shield, but I've can't recall ever seeing it connected in any PM1000 channel I've racked and the black lead has always been cropped short.

Cheers,
--
Don

The PCB mount holes on the Elements are as follows Pin 1 (primary high) is the circled pad then down the line of 4 pins on that side it's 1-2-3-4 then pin 5 (primary high) is across from pin 4  then 5-6-7-8 with 8 being across from pin 1.

So white goes into pin 5 and yellow into pin 8.  On the primary side we don't know. Try green into 1 and blue into 4. Check your phase, if it's 180 swap those leads.

Brown unconnected and black to Pin 6 (ground).

Zobel network? No way of knowing, maybe start with the PM 1000 schematic zobel.

Output (EA2623):
Red primary high hole (either one)
Org primary low hole  (either one)

Blue/Brown Sec high holes
Green/Black Sec lo holes

Good luck.

Mike

 

[ECS]

Just finished a Copper and it's working great!  I just wanted to confirm you've changed the heatsink setup on the BA512... all the photos I see are of a large black heatsink but my op-amp shipped with a plain metal standoff screwed to the transistors.  Is this how these op-amps are shipping now?

Thanks!

 

[useme2305]

ECS, that's interesting. i hope it's sufficient? can you post a pic of the new design?

 

[ECS]

Like I said the pre did work fine in a quick 5 minute mic test... I didn't check to see if the transitors or standoff got hot because the unit was enclosed.  Here are a couple of pictures... just looks a bit odd to me.

 

[Echo North]

Just finished a Copper and it's working great!  I just wanted to confirm you've changed the heatsink setup on the BA512... all the photos I see are of a large black heatsink but my op-amp shipped with a plain metal standoff screwed to the transistors.  Is this how these op-amps are shipping now?

Thanks!

Hi,

Yes this is a more common heatsink set up for this topology which generally runs a little cooler. If you look around many manufactures use this method (purple audio for one) or no heatsink at all.

The original heatsink was always more decorative, it was overkill. Rising material cost forced to either raise prices or use a more affordable method. Since it was more decorative we couldn't justify raising prices.

Jens the designer of this op-amp @ Eisen Audio has been running them with this set up in his console projects for years.

Mike

 

[ECS]

Thanks for the clarification Mike! 

Just wanted to confirm it was correct... aesthetically I don't mind at all, not like I'm going to be looking at the thing.

Thanks again for all the great projects... I've got another 1176 build planned very soon!

~Eric

 

[resilient]

Hi Mike,

Built an Elements Gold last night.  It is unfortunately not working.  I haven't gone through the resistors to double check all of those yet, but wanted to check in with you here.  I get some noise when rotating the output knob, but that's it.  Nothing through the DI or XLR.

I should also have a 500 extender soon to take measurements.  I'll also try to find a way to post a pic of my soldering.  Currently the pic is too big.

Any thoughts on the noisy output knob?

Brandon

 

[Echo North]

Hi Mike,

Built an Elements Gold last night.  It is unfortunately not working.  I haven't gone through the resistors to double check all of those yet, but wanted to check in with you here.  I get some noise when rotating the output knob, but that's it.  Nothing through the DI or XLR.

I should also have a 500 extender soon to take measurements.  I'll also try to find a way to post a pic of my soldering.  Currently the pic is too big.

Any thoughts on the noisy output knob?

Brandon

Well if it's not passing signal, you probably just have some DC in the output circuit you're amplifying.  Check all of your joints around those big caps by the input and output.  They can be tricky getting good flow into the ground plane pads.

Mike