LC,
Damn, those are nice looking boxes! When will you have pricing on the commercial version of the amps?
--Lenard
The heatsinks I'm looking at using are nearer to being square than oblong. Consequently they aren't "wide" enough to position the cap banks at the ends of the L modules as LC has shown in his pics. However the heatsinks will be "long" enough to position the cap banks above / in parallel with the L modules. Trust that shouldn't be a problem? ( I'm using width and length in the way suppliers describe the dimensions even though it's somewhat counterintuitive as far as I'm concerned.)
Hi
LC regarding resistor R3 R4 vs Supply, I ve done the test on one module (with 45V smps) and putting 100 ohm in parallel with the pot is not that a good idea, it limits the vas bias to max 260mv, which is not enough to get the max power. so finally I ve removed R3 R4 and I m now trying to tune this gear to get a famous 22V5rms. I m able to get that from the other module with 30ma vas bias (still with 220ohms). the module is now heating, so far no smoke from the pot. let see in one hour 🙂
EDIT: okay. max sweet spot for this module is 30ma vas bias and then I get a clean 19.5V into 6ohms. max. 35ma doesn't change 🙂
LC regarding resistor R3 R4 vs Supply, I ve done the test on one module (with 45V smps) and putting 100 ohm in parallel with the pot is not that a good idea, it limits the vas bias to max 260mv, which is not enough to get the max power. so finally I ve removed R3 R4 and I m now trying to tune this gear to get a famous 22V5rms. I m able to get that from the other module with 30ma vas bias (still with 220ohms). the module is now heating, so far no smoke from the pot. let see in one hour 🙂
EDIT: okay. max sweet spot for this module is 30ma vas bias and then I get a clean 19.5V into 6ohms. max. 35ma doesn't change 🙂
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Are the optional cable kits that you can buy to go with the Hypex SMPS compatible with the FO modules?
The cable set from Hypex has connectors on one side corresponding the connectors on the Hypex power supply. So on the other end of the cables you can mount the right connectors for the F.O module.
R.
R.
LC,
Are there going to be any updates to the L power modules in the next production run?
--Lenard
Are there going to be any updates to the L power modules in the next production run?
--Lenard
I see that now M version cost has risen from 88 to 110 euros
Are there any updated parts used ? Maybe 4 pole Mundorfs just like L version ?
If not, are there any plans for updating to 4 pole for M version in the future ?
Are there any updated parts used ? Maybe 4 pole Mundorfs just like L version ?
If not, are there any plans for updating to 4 pole for M version in the future ?
I guess it is still 88E for this supportive community and perhaps 110E for the "wide anonymous purchaser audience", would be a nice gesture ;-)
LC,
So....I found this case on Ebay for a pair of 1.4L power modules and was wondering if it would work.
New aluminum amp chassis /home audio amplifier case (Size 12.2 * 17.0 * 4.3in) | eBay
The seller doesn't provide any thermal ratings but I'm able to extract some values in order to calculate it:
Case External (WDH): 421 x 310 x 109 (specified)
Case Internal (WDH): 325 x 300 x 100 (specified)
Heatsink Depth: 100 mm (internal height of case)
Heatsink Height: 421 - 325 = 106 / 2 = 53 mm (half of the difference between external and internal case width)
Heatsink Length: 300 mm (internal depth of case)
Heatsink Base: 10 mm (specified)
Heatsink Pins: 30 (from picture)
If I plug those numbers in spreadsheet below......
[image]Image:Heatsink Calculator|none[/image]
Assuming my extracted values are correct, would the heatsinks keep the 1.4 L power modules at proper temperature (more or less)?
--Lenard
So....I found this case on Ebay for a pair of 1.4L power modules and was wondering if it would work.
New aluminum amp chassis /home audio amplifier case (Size 12.2 * 17.0 * 4.3in) | eBay
The seller doesn't provide any thermal ratings but I'm able to extract some values in order to calculate it:
Case External (WDH): 421 x 310 x 109 (specified)
Case Internal (WDH): 325 x 300 x 100 (specified)
Heatsink Depth: 100 mm (internal height of case)
Heatsink Height: 421 - 325 = 106 / 2 = 53 mm (half of the difference between external and internal case width)
Heatsink Length: 300 mm (internal depth of case)
Heatsink Base: 10 mm (specified)
Heatsink Pins: 30 (from picture)
If I plug those numbers in spreadsheet below......
[image]Image:Heatsink Calculator|none[/image]
Assuming my extracted values are correct, would the heatsinks keep the 1.4 L power modules at proper temperature (more or less)?
--Lenard
No FO L updates ahead. FO L started in June 2016, first batch of examples tested thoroughly over half a year period, all modifications done. Regular FO L series production started in November 2016, modules tested, no anomaly detected, all OK. So FO L will stay the same for quite some time, no need to change anything since it works perfectly.
FO M modules in production, now complete front-end the same as in FO L, price in post #1.
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45 °C recommended for idle heatsink temperature, that would allow app. 60 W of dissipation for FO L module. At +/-60 V you could set bias to 0,5 A of supply current. Higher the voltage less bias, lower the voltage more bias.
LC,
Just curious, does it make sense to purchase the FO L's and run them at +/-60 V? I might as well just go with FO M modules then, no? Or are there still sonic advantages with the FO L's?
I was planning on running the FO L's with the 2xSMPS1200A700 but to be honest, the speakers I'm considering building will only handle 200 W so the +/-83V powersupply seems overkill.
Any thoughts?
--Lenard
Lenard, I've stated +/-60 V as simple calculation example (see number 60, same numbers) since your heatsink allows 60 W power dissipation.
FO L makes sense using it at higher power levels, at higher PSU voltages like +/-85 V or similar.
FO L makes sense using it at higher power levels, at higher PSU voltages like +/-85 V or similar.
Most heatsink calculations by manufacturers are made with the maximum temperature being 80 degrees and not 40 as in your image. By changing it to 80 the thermal rating of the heatsink will be better (i.e. lower number) and more in line with the same rating you would get from a commercial heatsink brand like Fisher or Conrad.
No problem if you want to derate it for overhead but you won't be comparing the figures like for like from the heatsink manufacturers if you do.
Just to be clear 😛
Has it been done any alteration with the front end on the FO M modules lately?
Fluid,
I basically wanted to know if those heatsinks are big enough to handle the FO L at max power (for an extended period of time). Based on the images in message #3631, I have my doubts as LC is pairing a larger heatsink to his FO L's. (380x50x150).
--Lenard
New FO M will share the same front-end as it is present in FO L, meaning improvements to the FO M sound quality. FO L with Cap Banks has SQ better than most high-end amplifiers present on the market.
I'm lucky enough to have access to compare FO L to some best amplifiers in the industry. Lately we made head to head tests with these power amplifiers (mostly best models of brand named): Lamm 1.2 Reference, AVM monoblocks, Hegel, Electrocompaniet, MSB, Gryphon, Classe, Analog Domain, Rotel, ... etc.