I used it with a set of Vandersteen 2ci speakers. Those are I think 87 sensitivity. I had to crank it but it could get pretty loud. the 4ohm load should work to your advantage.
Could you biamp? The side woofer looks to cross over at 150hz. That is pretty low.
Could you biamp? The side woofer looks to cross over at 150hz. That is pretty low.
Thanks for your response!
Maybe I'll try biamping in future, but at the moment I am planning to use F6 as a stereo amp. Just finding the right loudspeakers... that 3-way DIY ScanBySide2 looks pretty nice and opinions about sound quality are fairly positive. Of course, there are plenty of more efficient loudspeakers, but I got really interested in these ones because of closed box construction, really deep bass, big side woofer, beryllium tweeter and almost affordable price. It is written that such a construction allows to listen on low levels without sound degradation (because of closed box and big woofer). Only efficiency is not as high.
But it seems to be, that F6 will have enough power to achieve comfortable loudness...
Left-Right balance
Hello everyone, my F6 is finished and sounds great. I do have a small issue in that the amplifier delivers more power on one channel (left -6 db vs. right).The bias voltages are the same on both channels (500 mV). Does anyone see where this could be coming from and how to fix this problem? Thank you very much in advance.
Hello everyone, my F6 is finished and sounds great. I do have a small issue in that the amplifier delivers more power on one channel (left -6 db vs. right).The bias voltages are the same on both channels (500 mV). Does anyone see where this could be coming from and how to fix this problem? Thank you very much in advance.
Thank you! Unfortunately everything was checked and the resistors matched before assembly so that there would be no differences between the two circuits. Would a lower bias value on the stronger channel be a solution? (or the opposite on the other channel). The listening difference is not very big, a stereo image shifted to the right by a third compared to the centre on a mono signal.
Yes, with DAC connected directly to the amp, config also tested with Onkyo amp and no balance issue.
Unfortunately not.
Alternate solution: to use the balance control on my DAC.
But do you think that lowering the bias setting on the right channel can do something?
Alternate solution: to use the balance control on my DAC.
But do you think that lowering the bias setting on the right channel can do something?
If one channel was down by 6dB both the stereo and mono would be uncentered, wouldn't they?
I was listening to music yesterday and on many songs the center image was moving to different locations. This seems to indicate that this could come come from the recorded source as well. I'm sure you have listened to enough to know it's not working right, just putting it out there.
I was listening to music yesterday and on many songs the center image was moving to different locations. This seems to indicate that this could come come from the recorded source as well. I'm sure you have listened to enough to know it's not working right, just putting it out there.
Thank you for your feedback. Yes, you are right, the spatial location varies between recordings. That's why with Adobe Audition I created a mono version of a recording, and the shift is there. The 6 dB is a correction made via the JRiver player. Measuring with a measurement microphone and white noise, the difference is more like 3.5 dB.
if you say that every part is checked, and if we presume that xformer is out of question (swapping them between channels is most practical way to investigate that), fact is that mosfets are sole parts with gain function in circuit
obtain another pair and replace them
obtain another pair and replace them
Have you measured this electrically as well as acoustically? With out a fancy anechoic chamber the room could be playing a part here too.
Thank you. I didn't swapped the input transformers, I will try to do so and replace the mosfets if they are not the root cause.
I keep wishing I could turn the gain up more. That's how much I like these F6s.
Might have to see about a preamp.
Might have to see about a preamp.
Build a Wayne’s BA2018 or IronPre.
I was really hoping not to complicate my system much more! 😉
The original plan was to morph these monoblocks into monsterblocks, balanced F6s that I could switch one half off to operate SE in the summer then switch everything back on for balanced operation in the winter. Nothing quite like a space heater to help out with these Denver winters, eh?
So, yeah, got these F6s in a monoblock pair and was thinking the balanced operation would help with the gain a bit more. I even have a second set of boards completely stuffed and ready to mount, just need a second pair of transformers and to build up the second set of PSU boards sitting in the bin o' parts. However, in a behind-the-scenes, scheming and dreaming email exchange with zman01, he pointed out the output impedance of the F6 was a bit high for running in balanced mode (0.5 Ohms). I immediately realized the error in my machinations and my evil audio genius pivoted to the possibility of some monsterblock F5s. All the bits are there in the chassis to add in the boards, psu and transformer and the F5 has extra bit o' gain and a nice svelte output impedance of 0.1 Ohms. Good room warming times!
In the meantime, need to finish these up and enjoy them for awhile. I say I'd like to turn them up some more but they already shake the house. They just sound that good. Time to go dial up the bias.
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