Wonderful Preamp!
Just started listening to the H2v2 using my Sony n-channel VFET. Lee Ritenour's "Dreamcatcher" and Djabe & Steve Hackett's BBack to Sardinia" sound holographic with a wide and deep soundstage. Experimenting now with speaker phasing.
Fantastic preamp for such a minimal circuit! Thanks to Nelson for sharing and to turion64 for distributing.
Just started listening to the H2v2 using my Sony n-channel VFET. Lee Ritenour's "Dreamcatcher" and Djabe & Steve Hackett's BBack to Sardinia" sound holographic with a wide and deep soundstage. Experimenting now with speaker phasing.
Fantastic preamp for such a minimal circuit! Thanks to Nelson for sharing and to turion64 for distributing.
Attachments
heyo. to anyone I promised to do component matching for, please let me know? I have been busy with some important personal emergency matters and unfortunately the H2 project has been totally forgotten about. I need to order the parts one day and I do not want to disappoint anyone!
Cheers,
me
Cheers,
me
The H2V2 in its case
Finally got the H2V2 in it’s Hammond case (1455K1201BK) along with M.J.’s PO89ZB wall wart filter. Running it with Nelson’s B1 preamp/buffer for now. Very nice soundstage but have to do more comparisons with & w/o. A nuisance a keep flipping the speaker leads…LOL…gotta build a lead flipping box of some sort.
Thank you Nelson!
Pete
Finally got the H2V2 in it’s Hammond case (1455K1201BK) along with M.J.’s PO89ZB wall wart filter. Running it with Nelson’s B1 preamp/buffer for now. Very nice soundstage but have to do more comparisons with & w/o. A nuisance a keep flipping the speaker leads…LOL…gotta build a lead flipping box of some sort.
Thank you Nelson!
Pete
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Looks good Pete!
I've been enjoying mine with a GlassWare FrontPanel stepped attenuator and thinking that's a good match, so will likely buy a case to fit. I'll have to try it with my B1 and maybe just case it up as an add-on as you have done so that I can move it around to various preamps.
Thanks again for distributing these!
I've been enjoying mine with a GlassWare FrontPanel stepped attenuator and thinking that's a good match, so will likely buy a case to fit. I'll have to try it with my B1 and maybe just case it up as an add-on as you have done so that I can move it around to various preamps.
Thanks again for distributing these!
I did replace C1 & C2 with Nelson's BOM selections (as compared to my original board build. R1 is mounted under the board so i could mount the screw terminals.
Cheers!
Cheers!
Hi Pete,
Package arrived for the Canadians. I will be contacting them by email and getting things sorted.
Note: wwwtttwww, please PM me your email address. This will make it easier for communication purposes.
Regards,
MM
Package arrived for the Canadians. I will be contacting them by email and getting things sorted.
Note: wwwtttwww, please PM me your email address. This will make it easier for communication purposes.
Regards,
MM
Tried to understand why there’s 3 pots: channel selector and L&R volume controls? Out of stock it seems..
Pete
Pete
It's an integrated 3-input selector/stepped attenuator. One knob for 6dB increments and another for 1dB for a total of 36 steps of stereo attenuation. The third knob is for input selection. Connections on the board are for three inputs (with separate grounds for each input) and one output which makes wiring easy.
Works well once you get used to the two knob volume adjustment and much cheaper than the dual-mono GoldPoint attenuators that I use on my B1.
While I wait for my H2 parts to arrive, I ordered some cheap toys from Aliexpress. The idea behind this is to be able to change the voltage on the jfet repeatedly without opening the case.
A 100R multiturn pot to replace P1 and R6 and a digital voltmeters to check the voltage. No idea if it will work, but worth trying 🙂
0.36'' Mini Digital Voltmeter DC 0 100V 3 wire 4 Bit Precision Voltage Meter Panel Tester For Electromobile Motorcycle Car 12V|Voltage Meters| - AliExpress
3590S 2 103L 3590S 100 10K ohm Precision Multiturn Potentiometer 10 Ring Adjustable Resistor + Turns Counting Dial Rotary Knob|multiturn potentiometer|precision multiturn potentiometeradjustable resistor - AliExpress
A 100R multiturn pot to replace P1 and R6 and a digital voltmeters to check the voltage. No idea if it will work, but worth trying 🙂
0.36'' Mini Digital Voltmeter DC 0 100V 3 wire 4 Bit Precision Voltage Meter Panel Tester For Electromobile Motorcycle Car 12V|Voltage Meters| - AliExpress
3590S 2 103L 3590S 100 10K ohm Precision Multiturn Potentiometer 10 Ring Adjustable Resistor + Turns Counting Dial Rotary Knob|multiturn potentiometer|precision multiturn potentiometeradjustable resistor - AliExpress
Hopefully the meters are accurate. 😉
I like my Hammond case since the top slides out so I can just leave it open until I’m happy with the voltage setting vs H2 level.
Pete
hahah! Have fun. 🙂
I'm wondering if anyone has posted about the output impedance of this preamp before? I need to add a couple of NE5532 buffers after the preamp as there will be multiple outputs, some with extra potentiometers and most of them with the possibility of a tube amp being connected. Buffers would allow me to add an extra pot without changing the output impedance!
My current schematic:
Input -> H2 → Potmeter → NE5532 buffer → Controlled out
................ ⇲→ Jumper → NE5532 buffer → Pre-out (no volume control)
Anyone with any tips, shoot! Otherwise, just interested in the output impedance of the H2. 🙂
I'm wondering if anyone has posted about the output impedance of this preamp before? I need to add a couple of NE5532 buffers after the preamp as there will be multiple outputs, some with extra potentiometers and most of them with the possibility of a tube amp being connected. Buffers would allow me to add an extra pot without changing the output impedance!
My current schematic:
Input -> H2 → Potmeter → NE5532 buffer → Controlled out
................ ⇲→ Jumper → NE5532 buffer → Pre-out (no volume control)
Anyone with any tips, shoot! Otherwise, just interested in the output impedance of the H2. 🙂
Output impedance is just a few hundred ohms. No need for an additional buffer in most use cases.
As we need a potentiometer after the pre-amp, a buffer would be preferrable just for theoretical resistance to the kind of variability that it provides. But a few hundred ohms sounds just fine then. I can work with that, thanks!
Interesting, I'm thinking of trying it out with the Allo Volt+ class D amplifier.
The board is definitely adding a sense of pleasant airiness to my normal preamp, which normally has a clean but speaker centric soundstage to it. I may go a bit lower on voltage setting to see what effect that may generate. It doesn’t match the beauty of what my B1K does to the music but it wasn’t meant to, was it?
Thanks Nelson.
Pete
Thanks Nelson.
Pete
I don't have a B1K to compare it to, but mine sounds absolutely wonderful. The soundstage has opened up completely with excellent imaging.
Have you experimented with slightly lower voltage at T2 for more than 1% distortion? My H2 V1 sounds best with 1.5% distortion.
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Have you experimented with slightly lower voltage at T2 for more than 1% distortion? My H2 V1 sounds best with 1.5% distortion.
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I'm new to all of this (received my kit, will hopefully find the time to build it soon), how do you measure the distortion?
I don’t have a distortion meter so I’m gonna have to do it by ear. A 1.5% setting is obviously gonna be a guess on my part.
The B1K adds the warmth of of kinda-tube. Not having a real "valve" preamp I don’t have a basis for comparison but the H2V2 definitely is an easy & positive addition…and I do have the speaker leads switched FYI.
;>)
P
The B1K adds the warmth of of kinda-tube. Not having a real "valve" preamp I don’t have a basis for comparison but the H2V2 definitely is an easy & positive addition…and I do have the speaker leads switched FYI.
;>)
P