You say: "Nice reply" and in next sentence you ask the question that clearly shows that you didn't read that nice reply at all
don't bridge it for 4 ohms
because you're anyway willing to make two stereo F5 and to bridge them - you'll have 4 "usual" channels ..... and you have 4 Eminence bass drivers ;
connect one bass to one channel - so called "vertical biamping"
much better drive conditions than bridged 4 ohms , where each channel see just 2 ohms
I just build up an UGS preamp. I heard it the last days a long time with F5. It has a very quick and fluent sound and unbelievable details.
http://www.diyaudio.com/forums/pass-labs/86300-ugs-adventures.html
good luck!
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I dont know if there is a need for this.
I use just a lonely F5 bi-amped with each channel driving 2 Alpha woofers.
The power seems there and well behaved. The top end I run the amp of the day, but the F5 surely is one of the best on top and bottom end for me.
That is a masterpiece. My other favorite (nonfiction) is
The End of Science by John Horgan.
I haven't read that one. I will be sure to check it out.
Can anybody direct me to instructions for setting the bias and any other complicated aspects there might be in constructing the F5 please, before I decide if I'm up to the task? I feel that I probably am capable, but had previously been attracted to the notion of building the Quad 405 Mk2, partly on the basis that it has dynamic bias setting, and remains within spec without adjustment until component failure. I'd prefer to build the F5, however, as it's almost certainly a better amp, which is saying something. I guess what I'm really asking is, does setting the bias on the F5 involve any tools beyond a decent soldering kit and a DMM?
Many thanks
Lucas
Many thanks
Lucas
Two DMMs would be usefull, one to watch the bias on one mosfet and the second to watch the DC offset on the output. But, it could be done with just the one switching the leads back and forth, back and forth, back and forth
Just remember to start with the pots set at their lowest value.
The F5 pdf on the First Watt web has instructions, also it's repeated numerous times in this thread.
Hi Tea-Bag ,
Please tell me if I understand well ...
Each Alpha 15 is run at you from a channel F5?
I mean you vertical-biamping?
I have tried but ... Supravox with an F5 is heard louder
Thanks!
Vitalica,
One F5 normal stereo kit drives 4 total alphas OB, two on left channel two on the right. The drive is like 1.5 or 2 ohms in parallel, but this is not a problem for this puppy. I use the T-Bass booster as well, and it does give a little more juice on the lower end, but still rolls off fast after 35hz. A electric cross over could give some bass boost like this too.
I have not tried vertical bi-amping, but I do have an army of amp's to work with. I will settle for this for now, it works. I am sure running one F5 per two Alpha's may bring more low end control, but these are quite efficient speakers.
MOSFET and JFET matching sockets
Does anyone have part numbers for machine sockets to use for temporarily holding Mosfets and another one for JFets -- for use in testing and/or matching?
I haven't done any testing yet. But, I figure it would be a good idea to be ready just in case I run into any issues. Plus, I have to order some parts after the holidays.
Thanks,
Steve
Does anyone have part numbers for machine sockets to use for temporarily holding Mosfets and another one for JFets -- for use in testing and/or matching?
I haven't done any testing yet. But, I figure it would be a good idea to be ready just in case I run into any issues. Plus, I have to order some parts after the holidays.
Thanks,
Steve
You mean I can connect the 2 x Eminence 15 "(4 ohm) to a bridge F5 without any problems?