[NXSTUDIO-DRUMMER]

Step bit or twist bit to drill your aluminum?

I’m pretty interested in learning more about working with Aluminum specifically for enclosures, etc, but realistically, I’ll just be using more basic, powered woodworking tools and hand tools. I’ve been doing some searching online as well, does anybody have a really good link or source for good basics or entry level type tutorials? 😇🤔

Step bits are typically better suited to drilling thinner aluminum sheets, it also deburs the aluminum too. Drilling thicker aluminum stock is better suited using a twist bit. Regardless of bits used, a center punch is recommended for accuracy. Cutting lubricant increases the lifespan of your drill bits. If your drilling aluminum stock thicker than 1/2", a drill press will benefit you substancially, keeping the hole drilled accurately to your specifications.

[nlitworld]

Made all the changes today, case looks fantastic...... but it doesn't fire. Not sure if I toasted a part on the board or if the little tiny button on the front of the board actually does something as a safety measure. ¯\_(ツ)_/¯   There is power to the board, the main cap has 58v across it, but can't verify power after that and no lights or any sound. I didn't pull off the volume pot just yet, as I figured baby steps in mods. Either way, I'll do some troubleshooting to find out and worst case scenario I start over after buying another for $80.

But it looks great in there. And yes I know I accidentally drilled the board a little crooked. 





P.S. if anyone is planning to desolder anything on this board, you'll want a minimum 60w 750° iron as their lead free solder sucks to melt. I went and bought a big fat Weller 900° gun just because of this.

[NIGHTFALL1970]

That looks so freaking cool!!😎 👍🤟

[NXSTUDIO-DRUMMER]

Lloyd,
If you need attenuator / switch extenders, here is one example available. I've personally never used them, therefore do your research to make sure they're a legitimate bussiness. https://www.audiyo.com/ext-kit.html

Using extenders, will give you more flexibility locating the PC board. If you relocate the PC board closer the rear of the enclosure, near the tube connectors and RCA terminals, your less likely to experience noise in the signal path. Simply by having shorter wire runs, will be beneficial. Longer wires have more surface area to act as an antenna, picking up electromagnetic interference (EMI) from sources like household wiring, radio signals, or for that matter any other audio associated equipment you have nearby.

[nlitworld]

Yeah my end goal is to remove the volume attenuator from the circuit rather than using an extender. If I need to keep it in there, I'll just keep it tucked inside the case with the volume up to max. I probably could scooch it back a little to limit cable lengths but wasn't super worried at the moment. Always a good tip though.

Just in case I did something legit bad, I have another on the way from Amazon. Joys of inexpensive items, trial and error is not a concern. Hoping to tear into the other one tomorrow night to figure what I did though.

[nlitworld]

It's alive! Sometimes you do a big oopsie somewhere and just need to start with a new board. Snagged a new one, mods all redone as well, and just left the DC input and wired a plug. I'll let it play for a while, before assessing difference, but right now it sounds great and looks even better. 

P.S. I still say doing these mods necessitates dual soldering irons. Also the little tiny button tab near the high pass knob is actually a ground connection. That's now hard wired to a star ground in the middle (purple wire).

-Lloyd

[nlitworld]

Update: after a week of playing off & on (probably 40 hrs) it's leaving a bit to be desired with a case of the uglies. Granted, I did get a new unit and reassembled the mods, plus the LPS really gives some serious oomph to everything. BUT, it's also currently highlighting some S's and T's a bit hot. Hoping everything calms down in a week or so, otherwise I'll maybe roll stock opamps back in and look at capacitor swap to try and smooth things out. I'm guessing I just made too much of a good thing with all the detail seeking combined with new board setting in. Just would like some more body in the 200-800hz range.

Right now, there are lots of things awesome about it as it's very articulate with TONS of kick down low. Fingers crossed 🤞 it smooths out a bit over next week or two. It's all good as my pre has tone controls, so the treble knob is just a little turned down.

EDIT* I did just figure out that my first amp that I messed up was a V3 dated 4/10/25 and my "new" one recently assembled is a V2 dated 1/08/25 and I did notice some differences in the circuit designs. Most notably around the low pass filter section but a few others elsewhere on the board. Weird that I would get a previous gen model even when I purchased both through Amazon roughly 4 months apart.

[NXSTUDIO-DRUMMER]

Tommy2tone,
Here is a photo of my power cable going between my Acopian A48HT850 and the Douk Audio A5.
Hope this provides a little clarity with the cable, since I am not able to forward an attached photo, on AC's PM messaging. The links I sent you through PM, has all the links of cable, and various cable connector options as well.

Enjoy your new Acopian A48HT850 Linear power supply. It brings the A5 and NX-Studio's to life, expanding their true capabilities.

Cheers!

[NXSTUDIO-DRUMMER]

Update: after a week of playing off & on (probably 40 hrs) it's leaving a bit to be desired with a case of the uglies. Granted, I did get a new unit and reassembled the mods, plus the LPS really gives some serious oomph to everything. BUT, it's also currently highlighting some S's and T's a bit hot. Hoping everything calms down in a week or so, otherwise I'll maybe roll stock opamps back in and look at capacitor swap to try and smooth things out. I'm guessing I just made too much of a good thing with all the detail seeking combined with new board setting in. Just would like some more body in the 200-800hz range.

Right now, there are lots of things awesome about it as it's very articulate with TONS of kick down low. Fingers crossed 🤞 it smooths out a bit over next week or two. It's all good as my pre has tone controls, so the treble knob is just a little turned down.

EDIT* I did just figure out that my first amp that I messed up was a V3 dated 4/10/25 and my "new" one recently assembled is a V2 dated 1/08/25 and I did notice some differences in the circuit designs. Most notably around the low pass filter section but a few others elsewhere on the board. Weird that I would get a previous gen model even when I purchased both through Amazon roughly 4 months apart.

Lloyd,
Being you have a new LPS and new A5, your correct,  it will take some time to burn both components in. In my case, my LPS Acopians had been used in a recording studio environment extensively, with many hours of usage. Therefore, they didn't require burn in time, luckily.

When you mention the sound being a little hot, are you using any silver wire interconnects between the amps?  They can be very bright sounding, versus copper wire interconnects. Is the new set up running quietly?

Is your preamp a true tube preamp or a hybrid combination?  This is where a tube preamp, tones down the analytical traits, typically associated to class D amps. This really benefits the A5 / LPS adding some tube warmth quality, as well as providing a larger sound stage.

If your still experiencing the sound being still too bright to your taste, after burning in for a few hundred hours, as you mentioned,re-installing the stock op-amps may tone it down on the top end some. Although, I still think my SX52B's sound better than the stock NE5532's, which are warmer sounding. In your case may be another soluction too, if your still experiencing harshness on the top end.

Have you noticed how much cooler the A5 is operating, now it's being powered with a LPS, versus a GaN power supply? Mine is literally a 100% cooler. Good to hear you have it operational now, so you can enjoy the benefits of you efforts put forth, on your DIY build. I like the wood chassis. Have you finished the wood, by staining and applying a finish coat yet?

Looking forward to hearing more imput regarding your new LPS/A5 build. I'm thoroughly enjoying mine! 

[nlitworld]

So chassis is all sealed with some minwax polyurethane stain. Nothing fancy, but it richened the color a little. The amp runs super cool in the new case. The bottom is aluminum sheet and barely over room temp to the touch.

As for preamp and cables, it's a legit tube preamp with tube rectification. I do have Gold Lion 12ax7 and nos RCA 5751 tubes in there which arent exactly known for smooth and mellow sound either. Cables are GR Research IC8 which are all copper but very articulate. I could try and swap my Hapa Ember cables in the mix but sound signature is very similar of articulate clear copper.

As for the sound of the amp itself, my plan is to let it burn in a couple weeks, also keeping it on 24/7 for a few days to see if it's better that way. I also found where I messed the old board up in the front corner, so I'll try to mend it (scary tiny smd resistor soldering). If that does work again, I'll swap back to V3. Douk did confirm some changes for bass response between the two, as well as the V2 low pass is 30-300 vs the V3 being 30-200 filter. All in all, the V3 was definitely better, but not exactly worth buying yet another just to get that board back.

So yeah, plans are to let it burn in, also set some nice miflex low pass caps in there (~8K ohm input) so a couple 0.22uf are on their way from Sonic Craft. If I really get bored, I'll swap those Nichicon for a set of small poly caps just for fun. Experimenting is worth the $30 just to tinker. If I was looking outright best sound, I'd look elsewhere. This is a fun little project and great to listen how each component changes the sound.

The good news of all this is it's pointing out I need to build my EL84 amp. 

[NXSTUDIO-DRUMMER]

Whatever LPS you choose if upgrading, here are some connectors and cable options, my friends and I have used with success.

Connectors for amp shown here $17 plus tax on Amazon. They have the simple option of using either banana plugs, or soldering wire directly to them.
https://www.amazon.com/gp/product/B0B7DD1P11/ref=ox_sc_act_title_1?smid=A25OSEB7LF3TDT&psc=1

Here is a link for a 5.5 mm x 2.5 mm DC barrel.
https://www.amazon.com/Viborg-DC25G-Connectors-Gold-Plated-Barrel/dp/B09L4TCTS5?th=1

Based on extensive listening experiences between my friends and I, with all our different Acopian models used, we haven’t experienced any EMI issues. A nice feature Acopian incorporates with their regulated linear supplies, galvanic isolation, which assist with reduction of EMI issues.

With interconnects, were using 1/2 meter length’s wire interconnects, between our 5.5 mm x 2.5 mm DC barrel plugs, going to our Acopian LPS’s.  Our AC Wall outlet cables are 2 meters in length as well.

You can use these very reasonably priced Spade connectors  between the Acopian LPS and the A5, as well as the AC Wall plug cable going to the Acopian LPS too.

https://www.amazon.com/Copper-Speaker-Connectors-Locking-Connector/dp/B07MPMJRY1/ref=sr_1_1_sspa?crid=2NQL9ZAXL4HS7&dib=eyJ2IjoiMSJ9.VVCSOwnpim044eLWLptqV8Vdg0C3MFfrA0MmemwiNaurui8I50kK1gcEsmxi-P68pHHt70l5mv-XgLqWoMplbOrGMbvHEOoov_kwnRkfhzB1gzJTe-TzlQW0riQ01f38-neUVin5A1mZiVEsKesQyn8aLNbcvcNyIDdz0SgGNGQMPgHKa0RS61Kh7nFdsOZvSIyLhGvpRyCHt5-m5MzCdMo68m661w4S1hErgX61GZI.C2YlLAVHG9rocIFSKBjH6RUaK35R-_6q0zdXlKWgeKs&dib_tag=se&keywords=viborg%2Bspade%2Bconnectors&qid=1762958513&sprefix=viborg%2Bspade%2Bconnectors%2Caps%2C115&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

Cabling wire? You have many options on the marketplace to choose from. Zip chord to sky’s the limit!

This is 16 strand OCC 7N Copper wire I personally use between my Acopian A48HT850 linear power supply and the A5's 5.5mm x 2.5 mm DC barrel plug. Its a nice quality wire, highly recommend. This is the link I used for my personal purchase.

https://www.aliexpress.us/item/3256807047639079.html?spm=a2g0n.detail.platformRecommendH5.8.28cfwN92wN92mm&gps-id=platformRecommendH5&scm=1007.18499.315613.0&scm_id=1007.18499.315613.0&scm-url=1007.18499.315613.0&pvid=d5f1a770-a408-491b-b0ea-17e91f60702e&_t=gps-id:platformRecommendH5,scm-url:1007.18499.315613.0,pvid:d5f1a770-a408-491b-b0ea-17e91f60702e,tpp_buckets:668%232846%238116%232002&pdp_ext_f=%7B%22order%22%3A%22120%22%2C%22eval%22%3A%221%22%2C%22sceneId%22%3A%228499%22%2C%22fromPage%22%3A%22recommend%22%7D&pdp_npi=6%40dis%21USD%2116.82%210.99%21%21%21119.09%216.97%21%402101d97817629695641737514ed841%2112000039902922754%21rec%21US%21%21ABXZ%211%210%21n_tag%3A-29910%3Bd%3Aa5eb23cf%3Bm03_new_user%3A-29895%3BpisId%3A5000000187461908&_universallink=1&m_page_id=qihiuxznawcaaczj19a792c52bd2a81c09da7ac731

Noticed they are selling these connectors cheap too.
https://www.aliexpress.us/item/3256806002157505.html?spm=oneshop.home.aeBusinessBuyAgainRecommend.3.2e047f6bw10fIq&skuId=12000036193551908&pdp_ext_f=%7B%22sku_id%22%3A%2212000036193551908%22%7D&aecmd=true&gatewayAdapt=glo2usa4itemAdapt

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Since I'm a huge advocate of safety, I wanted to provide a "free sound pressure meter app" link for iphone users. The source is from the National Institute For Occupational Safety & Health. I wanted to share for all AC members, to use under any conditions you may encounter within your daily environment.

Even if you have no need for the SPL meter app, perhaps the NIOSH website can provide additional education to serve you well.
Here is their link below:

https://www.cdc.gov/niosh/noise/about/app.html





_______________________________________ _______________________________________ _______________________________________ ___________________

For an audiophile listening room, use C-weighted decibels to accurately measure output across all frequencies. Set the meter to "Slow" response and use a dial setting (like 70 dB) to accommodate your target listening level, which is typically around 75–80 dB for calibration. This setting provides a more accurate picture of the sound's overall energy compared to A-weighting, which artificially lowers the impact of bass frequencies.

General Step-by-step guide:

Set weighting to C: Choose C-weighting, as it provides a flatter response across the frequency spectrum that better reflects human perception at higher volumes.

Set response to Slow: Select the "Slow" setting to smooth out fluctuations and get a stable average reading, especially when using a test tone like pink noise.

Set the range: Adjust the dB range on your meter to accommodate the expected levels, typically in the 70–90 dB range for speaker calibration.

Position the meter: Place the sound pressure meter at your primary listening position (the "sweet spot").

Measure each speaker: Play a test tone (like pink noise) and adjust each speaker's individual volume until the meter reads the same level for each channel. For example, calibrate the front left speaker to your target level first, then match all other speakers to that level.

Consider unweighted (Z-weighting) measurements: For a completely unadulterated measurement of the sound pressure, you can take a reading with Z-weighting (zero weighting) to see the raw output, but C-weighting is the standard for system calibration.

[nlitworld]

Mini-update. The sharpness is gone. Not sure if new board needed breaking in, new gigantic LPS caps needed to soften, or if leaving the amp on for 4 days straight has helped, but it sounds really really good now.

BUT, I'll have more break in time required after more upgrades next week. Just hope everything fits in this case...  Stay tuned.