Hello, voltages across R10 are 2,16 on one side and 2,30 on another. Huge offset?
Yesterday, I've plugged it to my system. It sounded OK.
I'm still not sure about one thing. Should I have an input return (grounded) connected directly to a circuit board INs middle pin (current setup). Or should I have it wired somehow via the pot?
Yesterday, I've plugged it to my system. It sounded OK.
I'm still not sure about one thing. Should I have an input return (grounded) connected directly to a circuit board INs middle pin (current setup). Or should I have it wired somehow via the pot?
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You are one of the few that get the CCS currents so close and above 200mA with 10R without a second try given the Mosfets Vgs spreads actually. Its not about offset, creates nothing such. Its to have the regs working in near current regions for both rails. If you have no buzz or hum on the speakers as the grounding is right now, let it be.
The carbon film , just like metal film, is usually cut to form a helix. Both will have the same inductance if the number of turns in the helix is the same and the diameter of the helix is the same.
Carbon composition does not have a helical form.
Damn! I put those pink Takman carbon film resistors! They're good but not for that purpose.
Is the Takman a flat pack rather than a cylinder?I put those pink Takman carbon film resistors!
The flatpack is very likely to have the carbon tracks cut to form a non helix, deliberately to keep inductance low.
Why does the BOM state carbon film?
This is the spec for mine:
http://www.partsconnexion.com/prod_pdf/takman_rex.pdf
This is the spec for mine:
http://www.partsconnexion.com/prod_pdf/takman_rex.pdf
The Takman has omitted Fe (iron) from it's construction. That might be a good reason for choosing it.
Low inductance is certainly not the reason. Takman state as much in the datasheet.
A small and easy to implement change in the production procedure could cancel much of the inductance effect. For some reason they chose not to adopt that almost zero cost procedure.
Low inductance is certainly not the reason. Takman state as much in the datasheet.
A small and easy to implement change in the production procedure could cancel much of the inductance effect. For some reason they chose not to adopt that almost zero cost procedure.
Two, three words on the sound, as I have spent a couple of days with DCB1 already.
System: QUAD 707 amp, Spendor S100 speakers, various sources.
DCB1 parts are mostly per BOM: Nichicon KG and PM caps, Vishay RN60D resistors, Alps RK27 20K pot...
I can compare this buffer only to my passive volume control. And first to notice is the dynamic control. All the sections are tight together like one fist now. Sometimes I had a too laidback, lazy reproduction with my passive. It got really faster. Especially, the bottom end. It is ridiculously good compared to earlier. Highs are not rolling off at any level. The stage is open and nice. The only downgrade, if it's legal to use this word, is a little less transparence in the mids. Though, this could be due to a feeling, that on my passive, mids were really outstanding, in a sense, that all other sections weren’t performing that great.
Thanks to everybody involved. I’m looking for enclosure and a pot extention kit now. Later, I will consider updgrading. Where should I start?
System: QUAD 707 amp, Spendor S100 speakers, various sources.
DCB1 parts are mostly per BOM: Nichicon KG and PM caps, Vishay RN60D resistors, Alps RK27 20K pot...
I can compare this buffer only to my passive volume control. And first to notice is the dynamic control. All the sections are tight together like one fist now. Sometimes I had a too laidback, lazy reproduction with my passive. It got really faster. Especially, the bottom end. It is ridiculously good compared to earlier. Highs are not rolling off at any level. The stage is open and nice. The only downgrade, if it's legal to use this word, is a little less transparence in the mids. Though, this could be due to a feeling, that on my passive, mids were really outstanding, in a sense, that all other sections weren’t performing that great.
Thanks to everybody involved. I’m looking for enclosure and a pot extention kit now. Later, I will consider updgrading. Where should I start?
I think if your getting more top and bottom, this emphasizes the mid's less. Just a thought.
That's what I was trying to say in a complicated way
Good point, Tea-Bag. I should let it burn in porperly.
I was thinking about Z-foil. Pricey stuff.
Charcroft Z-Foil Resistors for Audio homepage
But maybe I'll try TAKMAN with your advice.
Charcroft Z-Foil Resistors for Audio homepage
But maybe I'll try TAKMAN with your advice.
Two, three words on the sound, as I have spent a couple of days with DCB1 already.
System: QUAD 707 amp, Spendor S100 speakers, various sources.
DCB1 parts are mostly per BOM: Nichicon KG and PM caps, Vishay RN60D resistors, Alps RK27 20K pot...
I can compare this buffer only to my passive volume control. And first to notice is the dynamic control. All the sections are tight together like one fist now. Sometimes I had a too laidback, lazy reproduction with my passive. It got really faster. Especially, the bottom end. It is ridiculously good compared to earlier. Highs are not rolling off at any level. The stage is open and nice. The only downgrade, if it's legal to use this word, is a little less transparence in the mids. Though, this could be due to a feeling, that on my passive, mids were really outstanding, in a sense, that all other sections weren’t performing that great.
Thanks to everybody involved. I’m looking for enclosure and a pot extention kit now. Later, I will consider updgrading. Where should I start?
For more interesting mids, get a better pot. Switching or light.
I remember the S100 a bit thicker in low mids mainly in contrast to its higher regions. That is where voices mainly live and the Alps is a bit heavy there too. Try a cheap switch pot DACT style first, if it will work towards the right direction, then light is the ultimate next step in pots.
Thanks, Salas. I guess you have something similar to this with cheap mind?
DACT Type 21 Stepped Attenuator / Volume 20K for PreAmp | eBay UK
DACT Type 21 Stepped Attenuator / Volume 20K for PreAmp | eBay UK
These are even better and no problem with dust. I've been using one with my hot rodded DCB1 for a while now with excellent results.
VALAB 23 Step Attenuator Potentiometer 20K Stereo Log on eBay.ca (item 300420653208 end time 18-Apr-11 03:48:37 EDT)
VALAB 23 Step Attenuator Potentiometer 20K Stereo Log on eBay.ca (item 300420653208 end time 18-Apr-11 03:48:37 EDT)
These are even better and no problem with dust. I've been using one with my hot rodded DCB1 for a while now with excellent results.
VALAB 23 Step Attenuator Potentiometer 20K Stereo Log on eBay.ca (item 300420653208 end time 18-Apr-11 03:48:37 EDT)
Yes, I've been considering these before buying Alps. The price has put it off for later.
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