The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB

[xrk971]

Thanks for the update. Could the stereo image be result of switch in amps? Only way to say that or dual mono is to use the same amp, or build a dual mono and listen again. Which variant of the “F7” are you using as it’s not officially released as a DIY amp yet?

 

[jwjarch]

Hi X. The stereo image change is absolutely due to switching amps. All other variables are the same now. Preamp, source, speakers, etc. I just swapped back to the F7 clone this morning and the imaging I spoke about returned. BTW, the F7 clone are boards from Oreo382. Using them with Exicon laterals and genuine Toshiba J74/K170's from Spencer.

I keep going back to the F7. Sounds so good. But the BabelJ2 with SLB is giving it a real run for it's money. And yes, the next step it to go dual mono with the BabelJ2 and compare again directly with the F7.

 

[xrk971]

Thanks for checking that jwjarch? I can't remember if you ever built the Alpha Nirvana - wonder how that compares?

 

[jwjarch]

That one is still on my list X, along with the F3, ABBB, Aleph J, Sit3x, Singing Bush, Mini-Aleph, UDNeSS J2, Baby Huey EL34, AKSA 55, AB100, Cubie 2, M2X, Hifisonix KX, and JFet Circlotron. Uh oh.... I think I have a problem. Oh! I have all the parts for the Noir and Yarra pre-amps too! So many projects, so little time. I'm really making an effort not to let things sit on the shelf and collect dust though. Now that I have two Class A chassis to A/B compare it's making it easier to solder up different amps for listening.

I did build the ALPHA 20W boards back in the day. That project started me down a dangerous Class A path. I should swap back in and have a listen as well. I need to do that one of these days. I remember that being a very good sounding amp.

But immediately up next is The Singing Bush, using single rail SLB boards and true mono-block chassis.

 

[lukrez]

Hi X,

Unfortunately your/my SLB dual rail boards are still in the customs here in Germany. But I hope they will be with me soon.

I'm working on your BOM at Mouser and your linked project was really helpful. Cheers for that.

3 parts are not available at the moment and I do have some questions regarding the alternatives:

EEU-FS1H221L, EEU-FS1H102L and NTC_8D20 are not in stock right now.
Do you think I could use these parts instead?
https://www.mouser.de/ProductDetail...klGH9l0MkS3kHSiIq4WWmB8yFQcDBqMZWFf5B/ukBo213 for C21 and C22
https://www.mouser.de/ProductDetail...KSvXH%2BJ/NegKmlD54gL%2BRcTU8hyNmHL0//jlbuaN2 for C15-C18

For NTC_8D20 I haven't really found an alternative. Could you possibly give me an alternative?

As I said before, I'm doing Fab's USSA-5 with SLB PSU in a single dual mono chassis, could you tell me what I should/could use for soft start? I've seen your boards here: Soft as a Feather Pillow SFP Solid State Relay SSR Soft | Etsy Would this be a proper solution for the soft start?

Thank you,
Martin

 

[Vunce]

Hi Martin,

For C15-18, diameter 12.5mm/lead spacing 5mm (anything larger than 12.5mm will NOT fit)

https://www.mouser.com/ProductDetail/Panasonic/EEU-FC1H102L?qs=9ZlsGNkzaguGhmh0%2BerSXA==

For C21-22, diameter 8mm/lead spacing 3.5mm (10mm diameter can fit with some creativity )

https://www.mouser.com/ProductDetail/Panasonic/EEU-FC1H221B?qs=8Z%2BUzlV55zTBr2Yas7j9ow==

Alternative NTC:

https://www.mouser.com/ProductDetail/Amphenol-Advanced-Sensors/CL-60?qs=w3gjcs3NwciEQjXGFRAAAA==


Hopefully the boards arrive soon, Happy Building!!

 

[lukrez]

Hi Vunce,

Thanks for your quick response. I'll go for the Panasonic parts then. I've checked the NTC alternative and found out, that current rating (5A instead of 2A) and resistance (10 ohms instead of 8 ohms) changes... this is ok so? Pls confirm, thank you! Just want to be sure before ordering...

Regarding soft start, I've learnt meanwhile that my above linked SFF Solid State Relay SSR is speaker protection and not soft start for the PSU. Mbrennwa recommended this also for my build, so I think I'll use it.

I'm really looking forward to my AMP project... thank you Vunce!

 

[Vunce]

Yes, the CL60 is perfectly fine, actually I like it better because of its smaller size.
The 8d20 is a generic piece that can be purchased by bags of 10 or 20 cheaply on Aliexpress or eBay. The “20” represents its diameter.

I’ve noticed stock is becoming an issue with many part at most of the well known suppliers.

I use the SSR DC protection boards with my USSA5 also, it’s a wonderful amplifier

 

[xrk971]

Thanks for the help clarifying things Vunce.

Lukrez, the NTC is a ground loop breaker and anything from 8 to 15ohms (cold) is fine, but it should be able to carry the full current of your amp in case there is a safety issue - so 5A rating is probably good enough.

Good luck on your build!

The SFP solid state relay (SSR) soft start allows the amp to gracefully turn on without a large in-rush current. This will prolong the life of your amp and your mains circuits.

The ready to run (RTR) SSR speaker protection protects your speakers from turn on/off thump and DC errors.

 

[lukrez]

Thank you both.

Sorry for my noob questions... 5A is "probably good enough" - does it mean that 2A from the original BOM part https://www.mouser.de/ProductDetail/Semitec/8D2-07LD?qs=wgO0AD0o1vu91GQMooViLg== would be better? If so, then I would try to find the suggested part-nr somewhere else on ebay etc.

 

[xrk971]

5A is better as you want this to conduct more if called upon for safety reasons. However, that won't change how much hum reduction there is as a ground loop breaker.

 

[lukrez]

Great, thank you!

 

[Vunce]

..... does it mean that 2A from the original BOM part https://www.mouser.de/ProductDetail/Semitec/8D2-07LD?qs=wgO0AD0o1vu91GQMooViLg== would be better? If so, then I would try to find the suggested part-nr somewhere else on ebay etc.

Hi Martin,
These are the 6A NTC’s on the parts list:

10pcs NTC 8D-20 Inrush Current Limiter Power Thermistor 8ohms 6Amp 20mm 8 ohm | eBay

 

[lukrez]

Hi X,

the RTR SSR's arrived well packed yesterday in Germany - thank you! A lot quicker compared to the SLB boards.

I'm still having issues with my mouser project cart: now the STP110N8F6 (Access to this page has been denied.) are more or less out of stock, for my dual mono I would need 16 items, but only 9 are left in stock. Any idea what alternative I could use? Or anybody else who found the part online available in Europe?

Thank you all!

 

[Vunce]

I use these:
https://www.mouser.com/ProductDetail/Texas-Instruments/CSD19501KCS?qs=%2BFzhjShcsaKoXejjR2PZpw==

But, unfortunately they look out of stock also.
Stocking issues are becoming a major problem for lots of projects

 

[lukrez]

Thank you Vunce, I found a supplier here in Germany for your alternative:
CSD19501KCS TEXAS INSTRUMENTS - Transistor: N-MOSFET | unipolar; 80V; 100A; 217W; TO220-3 | TME - Elektronik Bauteile

I would get them there, as long as they are available... you can confirm that these work instead STP110N8F6 for Q1-Q8?

Cheers!

 

[Vunce]

Great news they are in stock for you.
Yes, I’ve used them in several SLB’s.

 

[jwjarch]

Another source for the STP110N8F6. I have ordered from LCSC and installed. They are genuine parts.

STMicroelectronics|STMicroelectronics STP110N8F6|MOSFET|LCSC

 

[xrk971]

Thanks for the help on locating the parts, guys.

It’s great to post your questions here in the thread vs PM’ing me as you can get a faster response and it helps others.

 

[donhughes111]

???

Zero at Mouser and Digikey and 35,000 at LCSC. Makes you wonder.

Don