Find that a surprising review. Mine produces a striking depth of Field/imagery. Best yet, after decades of Amps.
My wee grandaughters run out of the room looking for the source of the musical notes that they think are coming from another room.
Consider matching the F6s' capabilities in the Rest of your system?
Yes, that is what I meant. The soundstage is able to go behind the speakers. I meant it as a good thing.
I use a pair of Bordeaux speakers designed by speaker design works. I have had a lot of speakers go through my system and these are my favorite that I have had yet. They are critical of speaker placement but once you get them right, they are outstanding. Also, the only pair of DIY speakers that I have tried. My next will be the Elsinore's that Joe R. designed.
I use a pair of Bordeaux speakers designed by speaker design works. I have had a lot of speakers go through my system and these are my favorite that I have had yet. They are critical of speaker placement but once you get them right, they are outstanding. Also, the only pair of DIY speakers that I have tried. My next will be the Elsinore's that Joe R. designed.
Hi everyone,
I'd been enjoying my F6 for a while now, not even turning on my other amps as of late. However since yesterday I've been having some issues with fuses blowing as soon as I connect a source to the amp.
Here's what happened in order:
N.B.:
It was my first build and I have no knowledge of what in the signal path could explain the fuse to blow. I understand that means that more than 2A are passing through the fuse but what could explain it? Any idea on which components I should check?
Thanks for reading me
I'd been enjoying my F6 for a while now, not even turning on my other amps as of late. However since yesterday I've been having some issues with fuses blowing as soon as I connect a source to the amp.
Here's what happened in order:
- tried to put music on and noticed the amp was not on, although the power switch was
- unplugged everything, checked the fuse (->blown), replaced it. Figured the issue must have come from a mis-manipulation on my part
- plugged the power cord only and switched on -> amp turned and stayed on no problem
- plugged speakers and jack-rca cable back, switched on -> blown fuse again
- changed fuse, plugged another source on the cable and switched on -> yet another blown fuse
N.B.:
- Visual inspection shows no burn damage, no loose connection, nothing my eyes can see.
- The issue happened upon switching the amp on, not as I was using it (I'd listened to the amp for a couple hours earlier in the day).
It was my first build and I have no knowledge of what in the signal path could explain the fuse to blow. I understand that means that more than 2A are passing through the fuse but what could explain it? Any idea on which components I should check?
Thanks for reading me
I'd try simple first. It may not be the solution, but it takes very little time to check.
What type of inrush current limiting method are you using? NTC Thermistor or similar?
How much time between switching off and switching on?
If you are using a CL-60 or similar and not giving it time to cool between power cycles, that could be part of your issue. I like giving it 30s to a minute just for comfort, but it shouldn't take quite that long. During any future checks, be sure to give it some time between power off and on.
It does not explain the very first time the fuse blew or the 3rd not blowing, but, it's worth a brief consideration.
Next I'd check for for oddness around the inputs. This may also indicate whether there is an issue with your source and/or the amp itself.
Do you have shorting plugs or another way to short your inputs? If so, try shorting the inputs and seeing if it continues. L input shorted, R input shorted, Both shorted.
Once you've done that, let us know.
Edited to add - Posting at the same time as Dennis. Definitely do that alongside too (points to potential issue with the source). Good morning, Dennis.
What type of inrush current limiting method are you using? NTC Thermistor or similar?
How much time between switching off and switching on?
If you are using a CL-60 or similar and not giving it time to cool between power cycles, that could be part of your issue. I like giving it 30s to a minute just for comfort, but it shouldn't take quite that long. During any future checks, be sure to give it some time between power off and on.
It does not explain the very first time the fuse blew or the 3rd not blowing, but, it's worth a brief consideration.
Next I'd check for for oddness around the inputs. This may also indicate whether there is an issue with your source and/or the amp itself.
Do you have shorting plugs or another way to short your inputs? If so, try shorting the inputs and seeing if it continues. L input shorted, R input shorted, Both shorted.
Once you've done that, let us know.
Edited to add - Posting at the same time as Dennis.
Definitely do that alongside too (points to potential issue with the source). Good morning, Dennis.
Last edited:
Good morning Patrick!
Roosterwing: Sorry, I missed the part where you already tried changing the source. Is there a preamp in between?
The fuse not blowing without input or load is interesting. So assuming you have spare fuses to test with, you can try adding
back just one first to try isolate the issue?
Roosterwing: Sorry, I missed the part where you already tried changing the source. Is there a preamp in between?
The fuse not blowing without input or load is interesting. So assuming you have spare fuses to test with, you can try adding
back just one first to try isolate the issue?
Hi and thank you all for the recommendations. I'm currently awaiting a batch of fuses to try all of the things you recommended, they should arrive in a couple of days.
I think I did just what you described. After turning on the amp I noticed the jack wasn't plugged in and switched off, plugged it, then back on. Could this have damaged a component, explaining the short and therefore the fuse blowing?
No preamp! Just a jack to a computer, things are coming up slowly
I think I did just what you described. After turning on the amp I noticed the jack wasn't plugged in and switched off, plugged it, then back on. Could this have damaged a component, explaining the short and therefore the fuse blowing?
No preamp! Just a jack to a computer, things are coming up slowly
Roosterwing,
If you turn off the amp and quickly turn it back on after only a few seconds then quite likely the fuse will blow because the CL60 has not cooled back down and is ineffective as a current limiter. (I did this once in the last year while testing an amp on the bench.) ItsAllInMyHead's suggestion of giving it a minute between off/on is a great idea and will eliminate these nuisance blown fuses.
If you turn off the amp and quickly turn it back on after only a few seconds then quite likely the fuse will blow because the CL60 has not cooled back down and is ineffective as a current limiter. (I did this once in the last year while testing an amp on the bench.) ItsAllInMyHead's suggestion of giving it a minute between off/on is a great idea and will eliminate these nuisance blown fuses.
How much are you letting it get to temperature and how quickly are you cycling?
As others have pointed out, the thermistor(s) may be warm enough to allow too much inrush current.
What's the transformer type and VA? What's the total capacitance of the PSU? What's the fuse size?
Hello,
I have a pair of F6 mono-blocks that I built a few years back using the traditional power supply as outlined in the beginning of this thread. I've noticed that a couple people have built the F6 using SLB power supplies. Is there any theoretical advantage of using the SLB supply over the unregulated CRC supply in this application? I ask because I have an a pair of SLBs sitting around that I removed from another amp project. I am wondering if anyone has tried both types and heard a difference.
Thanks,
Alan
I have a pair of F6 mono-blocks that I built a few years back using the traditional power supply as outlined in the beginning of this thread. I've noticed that a couple people have built the F6 using SLB power supplies. Is there any theoretical advantage of using the SLB supply over the unregulated CRC supply in this application? I ask because I have an a pair of SLBs sitting around that I removed from another amp project. I am wondering if anyone has tried both types and heard a difference.
Thanks,
Alan
The SLB is also an unregulated supply.
Advantages would be no heat generated from rectification and lower output ripple voltage. Which would really help make for a quiet amp.
Sound wise is pretty subjective, probably have to experiment on your own setup for you to be the judge of that. If you have the SLB’s built already pretty easy swap. Voltage drop will probably be a couple more volts due to the capMx versus your stock CRC psu.
Advantages would be no heat generated from rectification and lower output ripple voltage. Which would really help make for a quiet amp.
Sound wise is pretty subjective, probably have to experiment on your own setup for you to be the judge of that. If you have the SLB’s built already pretty easy swap. Voltage drop will probably be a couple more volts due to the capMx versus your stock CRC psu.
Hi everyone, I received new fuses and ran some checks that helped me "fix" my problem.
It seems it all comes down to my ignorance on the role of the thermistor, combined with the current local temperatures (constant 30°C/85°F in my flat). Even though I'd been waiting 30s to a minute before turning the amp back on, I discovered that this just wasn't enough.
After switch off, probing the thermistor with a finger, I realized how hot it was and for how long it stayed so. In the current conditions it needs more than two minutes to go back to room temp. Now that I respect this long wait, things are fine and the fuses don't blow...
Anyways, good news overall. No (re)soldering involved, a lesson was learnt, and checking the offsets made me realize time (and maybe temperature changes) made the offset drift by quite a bit (21mV on one channel). So I've got that to set right.
Many thanks to all who chimed in, recommended or asked things. I'm back to my favourite amp,
Arthur
@6sX7 my transformer is 400VA, toroidal. Total capacitance 120K and fuse is 2A (running on 230V here). I think the number's ok as I followed guidance from this thread to size it.
It seems it all comes down to my ignorance on the role of the thermistor, combined with the current local temperatures (constant 30°C/85°F in my flat). Even though I'd been waiting 30s to a minute before turning the amp back on, I discovered that this just wasn't enough.
After switch off, probing the thermistor with a finger, I realized how hot it was and for how long it stayed so. In the current conditions it needs more than two minutes to go back to room temp. Now that I respect this long wait, things are fine and the fuses don't blow...
Anyways, good news overall. No (re)soldering involved, a lesson was learnt, and checking the offsets made me realize time (and maybe temperature changes) made the offset drift by quite a bit (21mV on one channel). So I've got that to set right.
Many thanks to all who chimed in, recommended or asked things. I'm back to my favourite amp,
Arthur
@6sX7 my transformer is 400VA, toroidal. Total capacitance 120K and fuse is 2A (running on 230V here). I think the number's ok as I followed guidance from this thread to size it.
Another F6 is born. Sounds great. Thanks for the build guid and this discussion forum. I could not have completed this project without them.
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