I will ...... to bridged F.O. Large !!! with SMPS1200A400 that allready have
Im thinking the same, to get more power and to get xlr innput.
I have Infinity tower that likes power
Or isit better to go for the 1200A700 if i need more power ?
Any sugestion how mutc watt i get with dual L FO ?
Insulator questions...
What is the case size of the Mosfets? TO-264?
The Manuel suggests Mica Insulators (size and thickness not specified), but I have also heard Kapton is good, but not necessary the longest lasting...
I know some testing was being done using Aluminium Oxide also, what was the outcome, in terms of Thermal transfer? The answer got lost in options.
Finally, I noticed in the photos posted on post #2545, that Lazy used relatively thick Insulators. I have read elsewhere that the thinnest possible is preferable. Is that the case with the FO modules?
Thanks,
What is the case size of the Mosfets? TO-264?
The Manuel suggests Mica Insulators (size and thickness not specified), but I have also heard Kapton is good, but not necessary the longest lasting...
I know some testing was being done using Aluminium Oxide also, what was the outcome, in terms of Thermal transfer? The answer got lost in options.
Finally, I noticed in the photos posted on post #2545, that Lazy used relatively thick Insulators. I have read elsewhere that the thinnest possible is preferable. Is that the case with the FO modules?
Thanks,
Best sonic results with AAVID 4180G. 
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New heart in old body
Hello all,
here is example how to put new heart into old body (sorry for bad picture quality). I know, it can make better, but this is good enough for me. Important is sound. Now I have true natural sound. All what is on compact disc come thru TA-E9000ES, FO 1.4 and Altec Lansing fiften into my ears. No more need to go to the opera or another concert. Thanks Andrej.
dd
Hello all,
here is example how to put new heart into old body (sorry for bad picture quality). I know, it can make better, but this is good enough for me. Important is sound. Now I have true natural sound. All what is on compact disc come thru TA-E9000ES, FO 1.4 and Altec Lansing fiften into my ears. No more need to go to the opera or another concert. Thanks Andrej.
dd
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Alumina (aluminium oxide) is much better than mica and kapton in conducting heat, see page 25 in EUVL's article for a comparison with 1mm thick alumina
I bought some Alumina on AliExpress.
Few pages back (set 50 posts per page) were posted.
First One S - 80 W/8 Ohm, 50 x 60 mm
First One M - 160 W/8 Ohm, 50 x 100 mm
First One L - 240 W/8 Ohm, 50 x 160 mm
S & L in final stage of PCB design.
What smps you recomend for the First One L ?
And isit possible to use 2 pcs for balanced innput ?
You're welcome dd16. That's exactly what I had on my mind designing First One, revive old amps with fresh heart and soul, congratulations.
Thanks for the info about aloxide thermal considerations Danny. Actually what I had on my mind speaking about sound quality by using AAVID 4180G is to have even more isolation from surrounding environment, meaning less capacitive coupling, less unwanted interference feedback, resulting in greater details precision, better soundstage and relaxed presentation. The cost of aloxide isolators compared to gained benefits is negligible.
Thanks for worthy contribution, I really should insert few crucial links in post #1, maybe over the weekend.
Leikis, yes 2 modules could be paired in full balanced input. For L version all Hypex SMPS having 400/700 suffix are preferred.
So to gett a fully balanced highpower amp i need.
4 x FirstOne L
2 x smps3k/700 (Hypex)
4U 400mm from Modushop.
Dc protection.
Any suggestion on how many watt i get in 8 and 4 ohm.
Please correck me if other parts is better
If 4 L modules is owerkill mabye 4 x M modules is better, with smps3k/400 ?
4 x FirstOne L
2 x smps3k/700 (Hypex)
4U 400mm from Modushop.
Dc protection.
Any suggestion on how many watt i get in 8 and 4 ohm.
Please correck me if other parts is better
If 4 L modules is owerkill mabye 4 x M modules is better, with smps3k/400 ?
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So to gett a fully balanced highpower amp i need.
4 x FirstOne L
2 x smps3k/700 (Hypex)
4U 400mm from Modushop.
Dc protection.
Any suggestion on how many watt i get in 8 and 4 ohm.
Please correck me if other parts is better
If 4 L modules is owerkill mabye 4 x M modules is better, with smps3k/400 ?
I am bit confused - do we need 4 modules for a balanced stereo amp? I am in the process of receiving two SMPS3kA400 power supplies. I still need to figure out the Amp modules. I thought the SMPS3KA400 would be the most flexible, being able to power multiple modules of S, M or L version, hence i ordered for it.
I suppose you can use a single end to balanced converter, but i prefer to use one amp module for each polarity from xlr signal.
ok, that makes sense. What are you using as a source and what speakers? I suppose the wiring will also be a different. i didn't see any wiring specifics for dual amp balanced input and speaker connections.
Please note, I am not too well versed with balanced/unbalanced and amp designs, so i am learning as i go along.
Source is Bluesound Node, optical out to MiniDSP 4x10HD, active system 4 vway system with passiv filter for tweeter. The FirstOne plan is for the Infinity Emim towers, they have 9 Emim midrange ribbons for each side. Coupled with 5 in series in center and 2 on top and botton i serie. Totaly around 7.5 ohm pluss the tweeter filter so its not so low impedance.
But i have tested some amps and i think 250w in 8 omh is minimum power.
I have used alot of Holton amp and very happy with them, but always curius of testing other amps
Source is Bluesound Node, optical out to MiniDSP 4x10HD, active system 4 vway system with passiv filter for tweeter. The FirstOne plan is for the Infinity Emim towers, they have 9 Emim midrange ribbons for each side. Coupled with 5 in series in center and 2 on top and botton i serie. Totaly around 7.5 ohm pluss the tweeter filter so its not so low impedance.
But i have tested some amps and i think 250w in 8 omh is minimum power.
I have used alot of Holton amp and very happy with them, but always curius of testing other amps
This is interesting. My setup is somewhat similar, but instead of minidsp 4x10, i have a nano digi. So, fiio X2 player -> Nano digi -> 4 x Fiio Dacs -> 6 channels of First one amps + stereo sub woofers powered through 2 x icepower 1000ASP. I was hoping to get 3 x First One on each SMPS3kA400, either 3 M version or one each of S, M and L for Tweeter, Mid and Bass.
Is the mini DSP 4x10 HD fully balanced?
Regards
Ani
I'm don't pay any fees to the US, unless it's included in the postage. The postage is a little steep for the larger enclosures, but I think that has more to do with the weight and DHL shipping than anything else. I pay no duty at my end.
Another First One is born.
After some delay while visiting the lakes (we are in summer here) I completed my F.O. in three days, of which half were only DIY (ugly) case work...
Everything went OK, safe for my tiny accessory Tx which couldn't cope with the task of powering the speaker protection modules (from another project), so I had to use a bulky EI Tx, which deprived some of the beauty of the amp...
Now in use in the "patio" system for braking-in and eventual re-calibration, so no comments yet about sound.
Heatsink warm to the touch.
Some ugly pictures...
Thanks LC.
After some delay while visiting the lakes (we are in summer here) I completed my F.O. in three days, of which half were only DIY (ugly) case work...
Everything went OK, safe for my tiny accessory Tx which couldn't cope with the task of powering the speaker protection modules (from another project), so I had to use a bulky EI Tx, which deprived some of the beauty of the amp...
Now in use in the "patio" system for braking-in and eventual re-calibration, so no comments yet about sound.
Heatsink warm to the touch.
Some ugly pictures...
Thanks LC.
Attachments
Leikis & ani101,
If you have fully balanced pre signal and know from start that you want to setup FO build as bridged there is benefits in below wire ring schematic setup. Special is PSU is not balanced so all the normal mess of common ground points is the force here and can be seen that signal ground is fully floating. Personal have not equipment to measure and document benefits but have amp that is setup as below verse single ended and subjective it is very hifi setup that also think should be logic when thinking over benefits in schematic. Member metallicus69 did a build as this over at Lacy Cat's VSSA thread which can be searched at, and only drawback spec told us by member Esperado that me miss very much seems to be speaker damping factor that will double.
Because bridging is normal a 4x power sum with same PSU and impedance load then PSU voltage and load needs attention. Lets take a FO example where at 8 ohm spec is 160W so bridged will output 640W. That would kill output devices and reason is each FO in bridged mode see only half of the load 4 ohm, so bridged mode needs lowered supply voltage probably to half, and you will have to ask Lacy Cat if 4 ohm load is allowed at all in bridged mode and supply voltage needs decreased further because FO bridged at 4 ohm will look into 2 ohm only.
A guess is FO modules bridged with 8 ohm loads and half supply voltage for M version will output 460W and S version will output 240W (numbers is FO modules output power to 4 ohm x2).
Link good info for bridging at Wikipedia https://en.wikipedia.org/wiki/Bridged_and_paralleled_amplifiers
If you have fully balanced pre signal and know from start that you want to setup FO build as bridged there is benefits in below wire ring schematic setup. Special is PSU is not balanced so all the normal mess of common ground points is the force here and can be seen that signal ground is fully floating. Personal have not equipment to measure and document benefits but have amp that is setup as below verse single ended and subjective it is very hifi setup that also think should be logic when thinking over benefits in schematic. Member metallicus69 did a build as this over at Lacy Cat's VSSA thread which can be searched at, and only drawback spec told us by member Esperado that me miss very much seems to be speaker damping factor that will double.
Because bridging is normal a 4x power sum with same PSU and impedance load then PSU voltage and load needs attention. Lets take a FO example where at 8 ohm spec is 160W so bridged will output 640W. That would kill output devices and reason is each FO in bridged mode see only half of the load 4 ohm, so bridged mode needs lowered supply voltage probably to half, and you will have to ask Lacy Cat if 4 ohm load is allowed at all in bridged mode and supply voltage needs decreased further because FO bridged at 4 ohm will look into 2 ohm only.
A guess is FO modules bridged with 8 ohm loads and half supply voltage for M version will output 460W and S version will output 240W (numbers is FO modules output power to 4 ohm x2).
Link good info for bridging at Wikipedia https://en.wikipedia.org/wiki/Bridged_and_paralleled_amplifiers
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