• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

First One - mosFET amplifier module

I own 2 stereo First One M 1.4 amps, each channel has its own SMPS1200 power supply, i wonder if i can bridge 2 channels and how. The goal is to get 2 mono amps (with twice power), i will drive >4 ohms loudspeakers. I know i'll need something to balance the input signal. Any experience in this field ?
 
View attachment 624298

Because impedance of the 4 pol Mundorf is 1 ohm at 40 Hz I took them out and replaced them with 4 Spraque 100 uf 100 v. I shorted input and output. Also I added 4x 0,5 ohm Duelund parrallel resistors in series with output. Now the bass is much better and midrange a little softer. I think this is the best amp I ever owned.

Hi !
did you use the vishay Sprague TVA 1346 100u 100V ?
any feedback on how you choose this one ? did you consider the PSU impedance or a pragmatique try&listen approach ?
thanks !

FYI I have one FO M V1.4 in its box for sale. used couple of days. send PM if interrested

hope we ll get some few words from LC one day
 
Hi guys :wave2:

Let not be fooled by me not being present here or on FO FB site or anywhere else on the web, our mission still uninterruptedly goes on, without any sign of stopping or slowing down. Main objective or better to say our credo to offer best possible amplifier modules on the market is unchanged, therefore R&D rolls on and as promised here, the team now think we have something unique, special, in our hands. First few public auditions were made lately around local exhibitions, otherwise thorough testing and listening is performed on daily basis in our company's listening room studio. Personally I don't see any weakest link in current amp's sch so from my point of view green light to go to the series production of the FO modules already given. Still some work to be done before wake up the production robots from standby mode. Please don't expect that this will happen tomorrow, still in near future. Please comment freely, will be back when will have something to say. ;)
 

Attachments

  • IMG_0077.jpg
    IMG_0077.jpg
    820.7 KB · Views: 594
  • IMG_0078.jpg
    IMG_0078.jpg
    817.9 KB · Views: 575
  • IMG_0087.jpg
    IMG_0087.jpg
    805.1 KB · Views: 494
  • IMG_0098.jpg
    IMG_0098.jpg
    841.9 KB · Views: 492
  • IMG_0147.jpg
    IMG_0147.jpg
    1,014 KB · Views: 476
  • IMG_0148.jpg
    IMG_0148.jpg
    1,002.9 KB · Views: 195
  • IMG_0154.jpg
    IMG_0154.jpg
    842.5 KB · Views: 203
  • IMG_0151.jpg
    IMG_0151.jpg
    994.6 KB · Views: 204
  • IMG_0159.jpg
    IMG_0159.jpg
    1 MB · Views: 199
  • IMG_0162.jpg
    IMG_0162.jpg
    646.1 KB · Views: 231
FO L measurements

Performance show, to see what new FO L version is capable of ... :)
 

Attachments

  • IMG_0171.jpg
    IMG_0171.jpg
    919.2 KB · Views: 213
  • IMG_0172.jpg
    IMG_0172.jpg
    825.7 KB · Views: 146
  • IMG_0173.jpg
    IMG_0173.jpg
    840.2 KB · Views: 111
  • IMG_0174.jpg
    IMG_0174.jpg
    753.6 KB · Views: 117
  • IMG_0176.jpg
    IMG_0176.jpg
    998.1 KB · Views: 119
  • IMG_0175.jpg
    IMG_0175.jpg
    1,015 KB · Views: 114
  • IMG_0177.jpg
    IMG_0177.jpg
    1,011.3 KB · Views: 106
  • IMG_0178.jpg
    IMG_0178.jpg
    990.2 KB · Views: 119
  • IMG_0179.jpg
    IMG_0179.jpg
    1,014.8 KB · Views: 114
  • IMG_0181.jpg
    IMG_0181.jpg
    890.3 KB · Views: 137
FO L measurements

... and conclusion. ;)
 

Attachments

  • IMG_0182.jpg
    IMG_0182.jpg
    1,012.5 KB · Views: 181
  • IMG_0183.jpg
    IMG_0183.jpg
    992.9 KB · Views: 172
  • IMG_0185.jpg
    IMG_0185.jpg
    932.9 KB · Views: 135
  • IMG_0184.jpg
    IMG_0184.jpg
    872.4 KB · Views: 132
  • IMG_0186.jpg
    IMG_0186.jpg
    955.3 KB · Views: 121
  • IMG_0187.jpg
    IMG_0187.jpg
    1,019.6 KB · Views: 124
  • IMG_0188.jpg
    IMG_0188.jpg
    979.3 KB · Views: 119
  • IMG_0189.jpg
    IMG_0189.jpg
    984.7 KB · Views: 118
  • IMG_0190.jpg
    IMG_0190.jpg
    1 MB · Views: 129
  • IMG_0191.jpg
    IMG_0191.jpg
    1 MB · Views: 136