You are just the opposite of the "Spade Haters" over in the Pass Forum. They won't spade (Faston) tab terminals on their PCBs - no matter how fat the wire. They prefer soldered flying leads for everything. I will post your example over there in my thread.
Why the Hate for Spades?
Why the Hate for Spades?
IMHO those connectors are sturdy and easy to use, and alot safer than the screwterminal with the exception of the type you can get a "fork-type" cable shoe clamped down in. But then I also believe that I can hear difference between signalcables...so I guess I'm an odd one.
As I doubt I'd hear any difference between a spade connected PS and a soldered wire PS.
LOL...There's certainly nothing special about the ALPS RK27 series of volume pots. Been there, done that.
Channel imbalance at lower levels is right on par with a good ole' $.75USD Alpha volume control:
16mm Pot 18
But if wasting the additional money on that big, pretty blue "ALPS" is your thing, by all means go for it.😀
FANTASTIC! The ALPS should suit you well even though it sucks a$$ as a volume control.🙄
Perhaps just perhaps...one day when you learn to move on to better volume controls like stepped attenuators from DACT, then you'll understand what a REAL volume control is all about.
Good luck with your future builds and Merry Christmas and Happy Swedish New Year!
Nothing wrong with a basic Alps RK09 series even at $3. When used properly with a high impedance JFET front end the sound control is butter smooth and I have not had issues with channel balance being off by any noticeable extent.
In my other two headamps, I use stepped attentuators, the type with only two resistors in the signal path. For this one I figured I'd use the ALPS as I only have the stepped attentuators in 10K and 100K. Given that I'll feed the headamp from a transformer output DAC, I know 50K was a safe bet.
Is there a corrected mosfet driver model for pspice? like UC2011 or something because these I have do not well.
thanks
thanks
Nearly completed the headamp. I am still waiting for the 715R's (RLC IIRC) light blue ones I have used before and I think they're good.
I used a 100uF/25V Silmic II for onboard PS as I could not fit the 470uF/25V Silmic II in any acceptable way.
The 470uF/25V ROA Cerafine on the output fits perfectly. I am considering the potential benefits (if any) of putting an SMD film cap across the output capacitor.
I have some AVX and Panasonic SMD film caps in various sizes and values.
I used a 100uF/25V Silmic II for onboard PS as I could not fit the 470uF/25V Silmic II in any acceptable way.
The 470uF/25V ROA Cerafine on the output fits perfectly. I am considering the potential benefits (if any) of putting an SMD film cap across the output capacitor.
I have some AVX and Panasonic SMD film caps in various sizes and values.
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Nicely done, Mayday! 
Looking forward to your first sound impressions. I can't remember to what tolerance you said you matched the BF862's.
Speaking of BF862's, they are end of life (EOL). I better stock up.
Looking forward to your first sound impressions. I can't remember to what tolerance you said you matched the BF862's.
Speaking of BF862's, they are end of life (EOL). I better stock up.
I went over the boards with the DMM, with PS wires connected as in the attached pics, I got about 22R between VCC and GND. Is that correct?
I had to use 10000uF/25V Dubilier (x2) and 1000uF/35V Panasonic FC as there's no way to fit two of the 22000uF caps on the board.
Edit: resistors on GND side are not yet populated.
I had to use 10000uF/25V Dubilier (x2) and 1000uF/35V Panasonic FC as there's no way to fit two of the 22000uF caps on the board.
Edit: resistors on GND side are not yet populated.
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Looking good Mayday!
BF862's are N-junction depletion-mode FETs, which are normally conducting (self-biasing capable) when no voltage is applied to the gate. 22R is probably result of natural conduction in the nominal no-voltage applied state. With a 20v rail that would be nearly an amp, nut max is limited by Idss of BF862 (around 10 to 25mA). I think nominal operating bias current is about 50mA to 60mA if I recall, so should go down once powered up.
BF862's are N-junction depletion-mode FETs, which are normally conducting (self-biasing capable) when no voltage is applied to the gate. 22R is probably result of natural conduction in the nominal no-voltage applied state. With a 20v rail that would be nearly an amp, nut max is limited by Idss of BF862 (around 10 to 25mA). I think nominal operating bias current is about 50mA to 60mA if I recall, so should go down once powered up.
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Hi,
Thanks 🙂
With the boards not connected via PS wiring I got 42R.
The devices are 13.4 to 13.8mA Idss.
I got the resistor needed to complete the headamp today. 715R as I didn't find 710R, does that matter?
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Sorry you were waiting on that. Not critical at all, anything from 220R to 2k would have worked
Well, no worries as I still need to get two more 5W resistors for the CRCRC filter.
Gives me the chance to work on the enclosure for the DAC/headamp combo.
Today I sanded and put the first layer of varnish on the wooden side panels.
Edit: I have two of the same enclosures, that's why there's 4 side panels.
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1W or even 500mW resistors can work for your CRC. We are taking flow of maybe 120mA here Class A so steady.
Put a second layer of varnish on the wooden sides.
I also started drilling holes in the alu-enclosure.
Also attached a picture of the DAC board and the XMOS board that will feed the headamp via edcor WSM transformers (600:2K4).
I also started drilling holes in the alu-enclosure.
Also attached a picture of the DAC board and the XMOS board that will feed the headamp via edcor WSM transformers (600:2K4).
Attachments
Nice work. You did a DIY DAC? Very cool. I like xmos USB adapter too. I got this and it works quite well. Has BB PCM5102 DAC. Nowadays I mostly use the Focusrite 2i4 2nd gen as a DAC and that sounds very good too. Capable of high speed rates.
New version Assembled XMOS U8 + PCM5102 + TDA1308 USB Coaxial DAC Sound Card 32bit 384K headphone Output ,Free Shipping-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
New version Assembled XMOS U8 + PCM5102 + TDA1308 USB Coaxial DAC Sound Card 32bit 384K headphone Output ,Free Shipping-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
Hi,
I have several DIY DAC's in different stages of completion lol.
Dual pcm1794, 3pcs populated Red Baron boards, a WM8740 board, two XMOS boards (one is the later XU208 IC), 3pcs audio-widget USB to I²S boards of which one is populated and flashed with firmware, a few WM8805 SPDIF to I²S boards (had those made by a board house, the dual pcm1794 too as it's a 4 layer board), one 8x TDA1387 board nearly done, one ES9018K2M board, two or three ES9023 boards and one analog metric completed dac with passive I/V and tube output.
A home etched WM8804 SPDIF to I²S board (most fine pitched board I've etched thus far).
I think I remembered them all lol