Could be done but with lower power supply voltage ie. +/-24 V and bias 2,5 A and large heatsink.
First One module has optimal bias for output mosfets, meaning 220 mA per both dies.
Multimedia Show 2014 report
Hi all
Here's brief report of my attendance on this year's Multimedia Show.
System consisted of Pioneer BDP-LX91 CD/BR player, First One v1.3 amplifier, First One v1.1 battery powered preamplifier, Zu Audio Soul Supreme speakers, MS Audio rack and High Diamond cables.
System sounded neutral, very dynamic on all sound pressure levels with good micro-details, as much as source allowed to.
I got positive feedback on relative comparison between v1.2 and v1.3 and in general visitors were very pleased with sound quality presented.
One comment from musician recently performing at the Ljubljana festival, bringing live professional recording CD made at national broadcast TV studios:"Most natural and realistic sound reproduction of what we heard at studio mastering in comparison to other systems on the show." He told me that he asked and listened to quite a lot of systems on the show with this recording and I believe him so.
Comments welcome.
Best regards, L.C.
Hi all
Here's brief report of my attendance on this year's Multimedia Show.
System consisted of Pioneer BDP-LX91 CD/BR player, First One v1.3 amplifier, First One v1.1 battery powered preamplifier, Zu Audio Soul Supreme speakers, MS Audio rack and High Diamond cables.
System sounded neutral, very dynamic on all sound pressure levels with good micro-details, as much as source allowed to.
I got positive feedback on relative comparison between v1.2 and v1.3 and in general visitors were very pleased with sound quality presented.
One comment from musician recently performing at the Ljubljana festival, bringing live professional recording CD made at national broadcast TV studios:"Most natural and realistic sound reproduction of what we heard at studio mastering in comparison to other systems on the show." He told me that he asked and listened to quite a lot of systems on the show with this recording and I believe him so.
Comments welcome.
Best regards, L.C.
Attachments
Thanks for the order, First One modules v1.3 prepared and send in a few days.
OK, to qualify myself for FO V1.3 version upgrade, here's my FO V 1.2 up and running. I'm quite impressed with the sound quality. I just need to get a better speaker to my system.
Attachments
wow your chassis is a pearl, what a nice heatsinks for First One modules, super looking amp. 😎
Yes you have definitely qualified for an upgrade manual.
Please guys send your photos or links of ready made First One amplifiers to:
first.one.amp@gmail.com
Upgrade manual will be send in a short time, thanks. 😉
L.C.
i am sure it,s mentioned before but can,t find it.how can i lower gain?its too much for my tweeters.
Hello all,
my system is finally up and running after 9 months of silence. First day it sounded really
bad but after about 100 hours or so things are getting, dare I say it , great. This will not be a detailed report but after hearing FO 1,3 in 2 high quality system I can say you get insane value for your cash. A will be back later with a more detailed report when I got everything tuned in.
I'm interested to hear what other FO owners have to say about the amp.
Enjoy the music
Peace,
Mikko
my system is finally up and running after 9 months of silence. First day it sounded really
bad but after about 100 hours or so things are getting, dare I say it , great. This will not be a detailed report but after hearing FO 1,3 in 2 high quality system I can say you get insane value for your cash. A will be back later with a more detailed report when I got everything tuned in.
I'm interested to hear what other FO owners have to say about the amp.
Enjoy the music
Peace,
Mikko
Hello Mikko,
amp is finished last night but only powered up for 20 min. DC output was around 15-20mV and power +-62V on both channels. Later tonight I will hook it up to my DAC...and post some pictures to qualify for v1.3 tweaks.
Enjoy!
picture
Sorry for low quality picture. I didn't follow Andrej's recommendation about grounding yet and only box is earthed. No hum, buzz or something similar. Impressions will be posted in a few days.
Loudspeakers KEF XQ40, DAC TP Buffalo III with IVY(soon SEN), Amanero USB to I2S with isolated USB power adapter and Acko's S03 for synchronous reclocking. I have some VDH D-352 Hybrid loudspeaker cables with Chord Chameleon plus interconnect. Inside amp, Neotech UPOCC twisted pair for input, standard Hypex power connector and VDH CS12 for output. All DC coupled. Box is HIFI2000 pesante dissipante 165mm. I've messed up with RCA position so input is little bit longer.
Working almost 3 hours with low level volume and it's slightly warm to the touch.
Sorry for low quality picture. I didn't follow Andrej's recommendation about grounding yet and only box is earthed. No hum, buzz or something similar. Impressions will be posted in a few days.
Loudspeakers KEF XQ40, DAC TP Buffalo III with IVY(soon SEN), Amanero USB to I2S with isolated USB power adapter and Acko's S03 for synchronous reclocking. I have some VDH D-352 Hybrid loudspeaker cables with Chord Chameleon plus interconnect. Inside amp, Neotech UPOCC twisted pair for input, standard Hypex power connector and VDH CS12 for output. All DC coupled. Box is HIFI2000 pesante dissipante 165mm. I've messed up with RCA position so input is little bit longer.
Working almost 3 hours with low level volume and it's slightly warm to the touch.
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Jay, I'm guilty as charged. To my defense, I'm actually " a little bit sick ".
Better stay home and " recover ".
Hmmmm, who to blame for this behavior ?
Better stay home and " recover ".
Hmmmm, who to blame for this behavior ?
Two options:
- resistors devider in front of the input ie. 1 k + 1 k devider will decrease gain by -6 dB, so the complete voltage gain will be +21 dB
- solder 1,5 k (2010 SMD case) resistor parallel to R5, R6 and 1,5 k (2010 SMD case) resistor parallel to R7, R8, thus reduce gain by -4 dB, so the complete voltage gain will be +23 dB
Of course by different resistors values (in both options) you could get any gain reduction needed. First option is easier to realize but it will significantly reduce input impedance.