DIYHFS Ultra Low Noise Filament Supply (Rev 3) 2-12V or 12-24v DC jumper selectable (Pair)


SKU: Mod-Fil-Rev3

Ultra Low Noise DIYHFS current source filament supply. 2.5A, 2.0v-12vdc (slow ramp-up 90% at 20 secs from turn on) output or 12 -24v without slow ramp-up. Jumper selectable. Of course voltage and current depend on heatsinking. Output noise <1mv. Output short circuit protected, overheat protected, output voltage continuously variable with on-board trimmer pot. Through-pcb vent-holes for cooling of critical parts. Also, can be mounted flat profile without heatsink by mounting regulator from the bottom and bolting regulator direct to chassis. Includes mounting standoffs and 4 pcs 0.47r resistors to trim input voltage. 

Regarding noise measurements (as some have asked): The self noise of the filament supplies is in the uV range but since there is always limited ripple rejection from any filter network, self-noise is swamped by in-circuit factors and is meaningless. If you measure a typical diode bridge you will observe several 100's mv output so this is a very significant noise reduction. We typically see 0.2 to 0.5mv at our amp output which is respectable even for a linestage.

Maximum nominal filament current supported is 2.5 Ampere, for this current is necessary to optimize the input voltage to the module using resistor in most cases. Filament currents much larger than 2.5 Ampere are not supported.

More information, please see manual here

price is for 1 pair (2 pcs). 

  Showcase 
LD Mono Max with P:USH Power Preview
 

Our universe became a little disordered last year when we introduced the single chassis LD dual mono. Due to escalating costs the 8 year old LD monoblock was not sustainable as a product on two counts: 1. cost of materials and manufacturing had almost tripled since the original Billie was offered for $700 (including all the upgrades we progressively built into the kit) and 2. shipping overseas by Fedex had doubled from <$200USD originally to >$400USD by 2009 (also due to the extra weight of all the upgrades and enhancements). The LD dual mono chassis gave us an opportunity to keep a sane selling price and also to forever dump the poison of electrolytics in the power supply and thus offer the one and only all film cap SET amplifier. This is where our universe became disarranged - the single chassis LD sounded better than the monoblocks. I guess not a surprise since the single chassis LD has everything the monoblocks had except minus one power transformer but plus 200uf of film caps. Raise the bar and that's what happens. In the meantime we've developed our own filament supplies and FCUPS (film cap universal power supply) which raises the bar again. I still had in mind to show some respect to the establishment. Here's a preview of what is coming: LD in Projekt chassis with FCUPS and filament supply standard. The extra cost of the FCUPS will be covered in part by the lower shipping cost due to the weight saved by not having huge chokes and caps. Also the added performance of the FCUPS is not subtle and is too good to not have. The discerning eye will notice this is our 91 circuit with Level 3 parts. This will be our standard for this LD monoblock. I will also do a version without the tantalums/teflon caps and some other expensive bits, but it will still be a 91. I fact, to maintain current naming convention and avoid confusion with previous circuits I'll probably name that one the Level 3 and this one the LD Mono Max. I'll also sell an 'open kit' version which will include all the basic infrastructure, chassis, transformers etc, for those that want to build their own way. So what's this P:USH Power business? Power for Ultimate Signal Headroom! Because the FCUPS with it's huge store of inductive energy and in virtual battery mode is in a totally different league than banks of caps, resistors and even big chokes in their little puddle of inductance. You really need to hear it - inductive energy store is totally better than capacitive energy. Like Iron Man beats Chickenman. So that the LD91 Mono Max with P:USH Power.



History of improvement:

Revision 3

  • Use Japanese Sanyo and Nichicon capacitors
  • Increased capacity by 50% to 9900uF. Less AC is needed amd less heats as by-product.
  • Double the size and efficiency of the heatsink.

Revision B2:

  • Added LED
  • Best quality parts: Schottky etc
  • Locked as a VCS and includes one more active device which gives a 20 second ramp up to full output voltage.

Price: USD $90.00