power bandwidth 100Khz or 3MHz...?
Hi LC,
Thanks for my 4 modules, just waiting on two 20 Ah 48 volt LiFe Po4 batteries arriving from China....!
One question please....On page 1 spec on this thread for the V1.2 module is
Frequency response is 3 Hz - 3 MHz (-3dB) This is important to me.
On the manual the new V1.4 : " Power bandwidth: DC to 100 kHz (-3 dB)"
Now usually power bandwidth is slightly less than Frequency Response, but a difference of 2.9MHz is a bit much!
Please confirm the Frequency response of the new V1.4 modules and the power bandwidth of the V1.2.
Thanks in advance
Derek.
Hi LC,
Thanks for my 4 modules, just waiting on two 20 Ah 48 volt LiFe Po4 batteries arriving from China....!
One question please....On page 1 spec on this thread for the V1.2 module is
Frequency response is 3 Hz - 3 MHz (-3dB) This is important to me.
On the manual the new V1.4 : " Power bandwidth: DC to 100 kHz (-3 dB)"
Now usually power bandwidth is slightly less than Frequency Response, but a difference of 2.9MHz is a bit much!
Please confirm the Frequency response of the new V1.4 modules and the power bandwidth of the V1.2.
Thanks in advance
Derek.
@ Overkill Audio
Lazy Cat linked some data v1.4 in post 2339 and manual for download in post 2340.
Find data captured below or this link First One V1 4 M Power Amplifier Module Class AB | eBay.
Lazy Cat linked some data v1.4 in post 2339 and manual for download in post 2340.
Find data captured below or this link First One V1 4 M Power Amplifier Module Class AB | eBay.
Attachments
Don't know a lot about V 1.4, but don't mixup the response curve of an amplifier (100KHz) that include the passive input low pass filter, and the closed loop bandwidth of the same amp without-it (3MHz ?).One question please....On page 1 spec on this thread for the V1.2 module is
Frequency response is 3 Hz - 3 MHz (-3dB) This is important to me.
On the manual the new V1.4 : " Power bandwidth: DC to 100 kHz (-3 dB)"
Now usually power bandwidth is slightly less than Frequency Response, but a difference of 2.9MHz is a bit much!
Please confirm the Frequency response of the new V1.4 modules and the power bandwidth of the V1.2.
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Hi guys
First One v1.4 has nothing to do with v1.2 since they're different and apart like Ferrari vs. Golf. v1.4 is DC coupled so it has +27,5 dB voltage gain from DC to upper limit, which is in both cases stated correct. If we look for small signals of let's say 12 Vpp, First One still shows some +20 dB gain at 3 MHz, but I would not suggest you to go higher with output voltage since in that case all zobel resistors would burn instantly. Also you can do full power with sinus 20% clipping at up to 20 kHz, zobel will survive, each module tested on Test station at quality control. Power bandwidth of -3 dB at 100 kHz is stated because that means half the power at which zobel will still survive, otherwise you could do more power or go higher with frequency but then you'll get smoke from zobel resistors and bye bye warranty. These numbers are all correct, they just shows capability and limitations of module to stay intact in warranty, out of that period you can go full throttle on your own risk.
Regards, L.C.
First One v1.4 has nothing to do with v1.2 since they're different and apart like Ferrari vs. Golf. v1.4 is DC coupled so it has +27,5 dB voltage gain from DC to upper limit, which is in both cases stated correct. If we look for small signals of let's say 12 Vpp, First One still shows some +20 dB gain at 3 MHz, but I would not suggest you to go higher with output voltage since in that case all zobel resistors would burn instantly. Also you can do full power with sinus 20% clipping at up to 20 kHz, zobel will survive, each module tested on Test station at quality control. Power bandwidth of -3 dB at 100 kHz is stated because that means half the power at which zobel will still survive, otherwise you could do more power or go higher with frequency but then you'll get smoke from zobel resistors and bye bye warranty. These numbers are all correct, they just shows capability and limitations of module to stay intact in warranty, out of that period you can go full throttle on your own risk.
Regards, L.C.
*On my opinion*, it is a good practice to separate the two measurements. We never need more than 200KHz of bandwidth (to keep the phase at 20KHz) with the input filter, and faster the amp in closed loop, better it is ...+20 dB of voltage gain at 3 MHz with low pass input filter in action.
I'm sure you will agree, CFA rulez
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Hello LC,
Any chance tracking numbers will be provided?
Bao
Any chance tracking numbers will be provided?
Bao
Hi guys
Just to inform you that the first batch of First One modules went out to travel the world, also one upgrade of a ready made First One dual-mono amplifier went to Sweden.
Also few tests were performed in recent week:
- ESP Monitor + Bassoon, First One clearly over performed MC² Audio T1000 power amp on Basson module, unbelievably but deeper more controlled bass with FO
- First One bi-amping of B&W 802-D3 with Anagram DAC source blow our minds
- my soul's favourite ALTEC Lansing Model Fourteen shows how good speakers were in eighties, match made in heaven, SONY's TA-N80ES didn't stand a chance
L.C.
FO final rev 1.4 test
Yesterday I finally heard FO1.4 at home.
We used anagram sonic2 and soekris r2r dac v1 as a source. Sonic2 is heavilly modded by lc. Soekris is as originally proposed, regulated power supply only. No extra mods.
The amp is really good now. It plays music in a more relaxed way, is more forgiving to a weaker source, but still preserves the little things I enjoy in the music.
Soekris has really down to earth presentation, the notes are naturally presented, lack of soundstage is obvious. When thing are complex the quiter sounds get masked by louder sounds.
Anagram still stays as a reference, bettering Soekris in all parameters.
Yesterday I finally heard FO1.4 at home.
We used anagram sonic2 and soekris r2r dac v1 as a source. Sonic2 is heavilly modded by lc. Soekris is as originally proposed, regulated power supply only. No extra mods.
The amp is really good now. It plays music in a more relaxed way, is more forgiving to a weaker source, but still preserves the little things I enjoy in the music.
Soekris has really down to earth presentation, the notes are naturally presented, lack of soundstage is obvious. When thing are complex the quiter sounds get masked by louder sounds.
Anagram still stays as a reference, bettering Soekris in all parameters.
Attachments
Thanks for a brief report.
I would really like to find better DAC than Anagram to be my new reference, so far no luck.
Otherwise I think it's time to put First One modules into an enclosure, enough dusting ...
Why don't you try -ECdesigns'- Mosaic T DAC
That way I will know in advance how my system will sound like in the near future
EC designs - Mosaic T
EC Designs Mosaic T DAC | HFA - The Independent Source for Audio Equipment Reviews
Cheers,
M.
Just ordered the v1.4
Fired Up! Just pulled the trigger and sent Lazy the $$$
Next step is the SMPS...
I am torn between going with two Hypex SMPS1200A400 or one Hypex SMPS3kA400. Naturally, the 3kA400 is a more cost effective option, but not "true" dual mono. Has anyone compared these two arrangements, I would be interested in "real world" differences both subjectively and academically. What are we getting for the 120 EURO more? I am a huge fan of huge soundstages and 3D sound, so if the "true" dual mono even has a little more of those attributes, I would go for the two 1200A400s.
Also, why we are on the topic of DACs. I have a Twisted Pair Buffalo III DAC that I have not assembled yet. Main reason being, I have not found a practical way to interface this kit to my PC for a multi-channel configuration, taking full advantage of the 32 bit capacity and other benefits of the Sabre Chip. My ultimate plan is to have one Buffalo kit running in stereo to my mains and a second kit set-up multi-channel to run surrounds and subs - best of both worlds then. But, alas, no "ideal" interface as of now...
Has anyone heard this DAC with ANY of the First One Amps? If so, what do You think?
I am open to other options here, especially in regards to no compromises for the main speakers even when running a multi-channel system.
Thanks for any suggestions You all might have.
Allen
Fired Up! Just pulled the trigger and sent Lazy the $$$
Next step is the SMPS...
I am torn between going with two Hypex SMPS1200A400 or one Hypex SMPS3kA400. Naturally, the 3kA400 is a more cost effective option, but not "true" dual mono. Has anyone compared these two arrangements, I would be interested in "real world" differences both subjectively and academically. What are we getting for the 120 EURO more? I am a huge fan of huge soundstages and 3D sound, so if the "true" dual mono even has a little more of those attributes, I would go for the two 1200A400s.
Also, why we are on the topic of DACs. I have a Twisted Pair Buffalo III DAC that I have not assembled yet.
Main reason being, I have not found a practical way to interface this kit to my PC for a multi-channel configuration, taking full advantage of the 32 bit capacity and other benefits of the Sabre Chip. My ultimate plan is to have one Buffalo kit running in stereo to my mains and a second kit set-up multi-channel to run surrounds and subs - best of both worlds then. But, alas, no "ideal" interface as of now...Has anyone heard this DAC with ANY of the First One Amps? If so, what do You think?
I am open to other options here, especially in regards to no compromises for the main speakers even when running a multi-channel system.
Thanks for any suggestions You all might have.
Allen
Fired Up! Just pulled the trigger and sent Lazy the $$$
Next step is the SMPS...
I am a huge fan of huge soundstages and 3D sound, so if the "true" dual mono even has a little more of those attributes, I would go for the two 1200A400s.
...
Thanks for any suggestions You all might have.
Allen
Thanks Allen.
No doubts, two SMPS1200A400 connected as described in manual, best 3D imaging.
Sabre DAC - wide curve around, heard many, sold all of them. Discrete R-2R or AD1955 many in parallel that's the way.
Why don't you try -ECdesigns'- Mosaic T DAC
That way I will know in advance how my system will sound like in the near future
EC designs - Mosaic T
EC Designs Mosaic T DAC | HFA - The Independent Source for Audio Equipment Reviews
Cheers,
M.
WOW thanks for this suggestion, front view stealth design, lost in the rack.
Discrete ladder & output stage.
L.C.
