F5 for a first DIY project?
Hi everyone,
I'm very curious about the F5 but have never built an amp before. How suitable would this amp be for a first project? I've seen a few people mention the possibility of a PCB on this thread, but it's not clear whether there will be one made available. PCB coming?
It's also unclear to me what the approximate cost of parts for this build would be. Any rough estimates?
Thanks for the help. Looks like a great amp. Look forward to diving into DIY.
-Roscoe
Hi everyone,
I'm very curious about the F5 but have never built an amp before. How suitable would this amp be for a first project? I've seen a few people mention the possibility of a PCB on this thread, but it's not clear whether there will be one made available. PCB coming?
It's also unclear to me what the approximate cost of parts for this build would be. Any rough estimates?
Thanks for the help. Looks like a great amp. Look forward to diving into DIY.
-Roscoe
Re: F5 for a first DIY project?
To be honest, you might consider cutting your 'first amp' teeth with a gainclone first, to learn basics on building power supplies, chassis and basic soldering (assuming you're also an electronics newb).
Cost for the 'guts' is nothing typically (probably about $30 as a rough estimate). It's the power supply and the heatsinks that will set you back.
And of course, here's the requisite Mastercard quote:
The sense of satisfaction from listening to your first DIY Pass Amp: Priceless
roscoeiii said:Hi everyone,
I'm very curious about the F5 but have never built an amp before. How suitable would this amp be for a first project? I've seen a few people mention the possibility of a PCB on this thread, but it's not clear whether there will be one made available. PCB coming?
It's also unclear to me what the approximate cost of parts for this build would be. Any rough estimates?
Thanks for the help. Looks like a great amp. Look forward to diving into DIY.
-Roscoe
To be honest, you might consider cutting your 'first amp' teeth with a gainclone first, to learn basics on building power supplies, chassis and basic soldering (assuming you're also an electronics newb).
Cost for the 'guts' is nothing typically (probably about $30 as a rough estimate). It's the power supply and the heatsinks that will set you back.
And of course, here's the requisite Mastercard quote:
The sense of satisfaction from listening to your first DIY Pass Amp: Priceless
KSTR said:It's, by design, not the king of damping factors. With a speaker very sensitive to that and with very irregular and lowish impedance (IOW: older Kappa or so) it might be suboptimal.
Of the Zen and FW series, it would be the best, since it has a DF
of 80 and will drive 2 ohms without burping.
I don't believe, however that I would point it at a speaker with both
a low impedance and a low sensitivity.
Reactance is not an issue. The performance is slightly more robust into
a fully reactive load vs a resistive load of the same impedance.
The more this goes on, the more interested I become, however the wait to read the details is frustrating. Jaycar have no issues of the relevant AX that I could find, and I got that typical "I dunno" response when asked for an ETA.
The common supplies for the different FW designs is intriguing: I have a 5 way project under development and the 3 channels from 200Hz up give a lot of opportunity to mix and match different models with less expense.
I've been wondering about the F1 with compression drivers, and an F4/F5 for the mids.
The common supplies for the different FW designs is intriguing: I have a 5 way project under development and the 3 channels from 200Hz up give a lot of opportunity to mix and match different models with less expense.
I've been wondering about the F1 with compression drivers, and an F4/F5 for the mids.
If the DF is referred to 8Ohms, then my sims -- @1.4A bias, 560R I-V resistors, K170&J74 FETs -- have been pretty close, using IRFP244 and FQA9P25 models, though a bit on the defensive side (DF ~ 60@8R). Thanks for that breadcrumb.Nelson Pass said:Of the Zen and FW series, it would be the best, since it has a DF
of 80
- Klaus
seventenths said:I've been dying to read the article, but my local news stand still has the April issue out... Soon, I tell myself
checking it daily
7/10
Why not subscibe.??Much cheaper and gives the mail box some meaning besides bills!!!
sandstorm33 said:
Why not subscibe.??Much cheaper and gives the mail box some meaning besides bills!!!
I will indeed. I was sucked into this mess just about a year ago with a simple altoid tin headphone amp... HaHa, if I'd have only known then what it would lead to, I would have subscribed earlier
instant gratification? what?,
7/10
Nelson Pass said:
Of the Zen and FW series, it would be the best, since it has a DF
of 80 and will drive 2 ohms without burping.
I don't believe, however that I would point it at a speaker with both
a low impedance and a low sensitivity.
Reactance is not an issue. The performance is slightly more robust into
a fully reactive load vs a resistive load of the same impedance.
Nelson
My Quad 989s go down to about 4 ohms and are probably 86 db. Would they be in the usable zone do you reckon?
BTW, I have a pair of DIY F4s, voltage gain courtesy of a valve buffer using some old 76 valves, volume controlled by a TVC. This set up drives the 989s with no difficulty and sounds just fab. The grass is always greener though . . .
dhole said:I was thinking the toroidal for the F5 could be around 200VA 2 x 18v ?...is this big enough. What are people using ? Nelson ?
dave
hehe
for one channel - just usable
dhole said:I was thinking the toroidal for the F5 could be around 200VA 2 x 18v ?...is this big enough. What are people using ? Nelson ?
dave
I would like to recommend to read ZV5 article.
It explains the concept and real size of the transformer in detail.
If I got things right, we have, using some safety margin :
1.4A * 48V = 67W idle dissipation
plus about 140W R.M.S. for a 2 ohm load driven to the clipping limit (which means some 280 instant watts alternating between rails under worst-case assumptions): Pd(rms) = 0.5 * 24V^2 / 2R
A 300VA per channel looks OK to me, pretty much on the safe side.
- Klaus
1.4A * 48V = 67W idle dissipation
plus about 140W R.M.S. for a 2 ohm load driven to the clipping limit (which means some 280 instant watts alternating between rails under worst-case assumptions): Pd(rms) = 0.5 * 24V^2 / 2R
A 300VA per channel looks OK to me, pretty much on the safe side.
- Klaus
flg said:I don't believe N.P. actually gave that much detail regarding the P.S.
Let’s try to see things in positive way.
In general, papa respects that we are not really children, without showing detailed figures. Therefore, he likes to focus more on essential concept and principle in his writing (detailed sometimes). Meanwhile, getting detailed figure for our purpose is an apportionment we need to tackle, based on the given principle.
Babowana said:
Let’s try to see things in positive way.
In general, papa respects that we are not really children, without showing detailed figures. Therefore, he likes to focus more on essential concept and principle in his writing (detailed sometimes). Meanwhile, getting detailed figure for our purpose is an apportionment we need to tackle, based on the given principle.
Totally agree.
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