New Build Recommendation: F5 Turbo v3 or Aleph X
Just planning on my first DIY amp. Lots of reading and research has led me to the F5 turbo v3 and Aleph X. So I'm trying to decide which amp to build.
My speakers are max 200W and 4 ohm and I'm planning on monoblocks.
So, what are the differences between these amps in regards to the following:
- build complexity
- best suited to higher power output
- differences in sound &/or sound quality over bass, mid & high (subjective I know but people's opinion would be appreciated)
Thanks in advance for replies.
Just planning on my first DIY amp. Lots of reading and research has led me to the F5 turbo v3 and Aleph X. So I'm trying to decide which amp to build.
My speakers are max 200W and 4 ohm and I'm planning on monoblocks.
So, what are the differences between these amps in regards to the following:
- build complexity
- best suited to higher power output
- differences in sound &/or sound quality over bass, mid & high (subjective I know but people's opinion would be appreciated)
Thanks in advance for replies.
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[...in case anyone else is trying to make the same decision]
....after a bit more research and discussion with DIYaudio member oneplustwo (thanks heaps) I've decided to go with the F5 Turbo V3 for the following reasons:
- There is more information & discussion out about the F5 and its newer versions.
- The F5 has been around for a long time and is a tried and tested amp.
- The schematics are readily available.
- It is reported to be a simpler build than the Aleph X.
- There is enough power in the v3 for my speakers and my needs, and the only reason I was going to go for the Aleph X was for the extra power.
So it's F5 Game On time!



....after a bit more research and discussion with DIYaudio member oneplustwo (thanks heaps) I've decided to go with the F5 Turbo V3 for the following reasons:
- There is more information & discussion out about the F5 and its newer versions.
- The F5 has been around for a long time and is a tried and tested amp.
- The schematics are readily available.
- It is reported to be a simpler build than the Aleph X.
- There is enough power in the v3 for my speakers and my needs, and the only reason I was going to go for the Aleph X was for the extra power.
So it's F5 Game On time!




What is the impedance and efficiency of your speakers? Model and make?
Impedance: 4 ohm
Efficiency/Sensitivity: 90dB
They are Krix Neuphonix (Krix experience sound - Home Entertainment - Product Detail - Neuphonix)
An externally hosted image should be here but it was not working when we last tested it.
From Krix website:
Frequency Range: 30Hz - 40kHz in room response
Power Handling: Maximum 200 watts RMS amplifier power
Sensitivity: 90dB for 2.83 volts at 1 metre
Configuration: 6 driver 3-way bi-wirable / bi-ampable
Bass Driver(s): 4 x nominal 130mm (5") coated paper cones. 26mm (1") voice coil wound on high powered aluminium former provides good linearity and driver control at large cone excursion
Midrange Driver: 1 x nominal 130mm (5") coated paper cone. 26mm (1") voice coil wound on high powered aluminium former, using copper shorting ring and oversized magnet for lower distortion
Tweeter: 26mm (1") dual concentric diaphragm with wave-guide centre plug for controlled directivity. Non-reflective dual chambered magnet structure with copper shorting ring to lower distortion
Crossover Points: 340Hz & 2.5kHz
Impedance: Nominally 4 ohms
Enclosure Type: Dual chambers – sealed midrange chamber, with bass reflex main chamber, rear vented with internal / external flaring
Dimensions: 1065mm high x 230mm wide x 430mm deep
Material: 19mm MDF enclosure, heavily braced, with 25mm MDF front baffle
Finish: Lacquered timber veneer
Volume: 68 litres internal
Weight: 31kg each
with 4ohm impedance, and 90db at 2.83V= 90db at 2W/1M. or 87db 1W/1M.
Thanks for the calculations, AudioSan.
Also I was trying to find your review/impressions of the F5 Turbo v3 but couldn't see a post. Can you point me in the right direction, if it exists?
they're not finnished yet. still missing some alu for the chassis.
OK Thanks. I'll keep an eye out for it later.
- It is reported to be a simpler build than the Aleph X.
😕 Who has built one? Using what boards? I'm only curious, I didn't think there were any out in the field yet.
The other 100WPC Pass DIY solution is a pair of F4 and a balanced preamp. Nobody ever remembers that...
alephX or any balanced F4 or what ever, is not recomended for 4ohm speakers. a high bias/low voltage F5turbo is better suited for that job.
And what about your music taste? I am A/Bing F5Tv2 and Aleph 60 now... Tough choice... 🙂
I like 90's indie rock, electronica, and blues. I do like to crank The Pixies every now and then for sure.
I read some reviews on the Aleph and F5 and it seemed that the F5 was a bit more detailed which is what I prefer. I like to be able to hear the individual instruments and the voice variation as the singer holds a long note.
😕 Who has built one? Using what boards? I'm only curious, I didn't think there were any out in the field yet.
I think oneplustwo built some. And also Eric (also a member on DIYaudio). See Aleph-X 100w Amplifier Construction Notes.
I'm not sure of the boards they used.
The other 100WPC Pass DIY solution is a pair of F4 and a balanced preamp. Nobody ever remembers that...
I looked at the F4 and F5 on firstwatt.com and saw they both had the same power out. I focussed on F5 since there was a builder's thread and seemed to be more info available for it. I knew of it but wasn't around when it came out so didn't 'remember' it as such. Did it compare well with the F5? What's the advantage/disadvantage of balanced vs unbalanced?
I'm reading "Designing Audio Power Amplifers" by Bob Cordell to understand the terminology better and the importance of various components of an amp so it's probably outlined in there too.
Go for F5T, brilliant amp, you will love it!
Righto. Will do.
I'm really looking forward to getting into it probably later in the year.
Any particular version you recommend? I was just going to do the v3 since it has more power and was the latest design for the F5.
It is the same time design as any of F5T 🙂. It depends on how loud do you like your music. I have 89-90db 6 Ohm speakers and F5Tv2 is more than enough for me 🙂. I think it is better to go lower in rail voltage, but higher in bias and maybe more outputs. You can still have 4 pairs/ch and 32V rails.
It is the same time design as any of F5T 🙂. It depends on how loud do you like your music. I have 89-90db 6 Ohm speakers and F5Tv2 is more than enough for me 🙂. I think it is better to go lower in rail voltage, but higher in bias and maybe more outputs. You can still have 4 pairs/ch and 32V rails.
Ok thanks for the advice. I'll keep it in mind as I begin to collect the parts I need.
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alephX or any balanced F4 or what ever, is not recomended for 4ohm speakers.
Hmmm... I must have missed this somewhere along the way - no one ever told me that I can't drive my 4-ohm speakers with my Aleph-X amps 😀 These amps handle my giant open baffle speakers with ease!
Everything you need (except boards) to build an Aleph-X can be found on my web page - see sig link. F5 boards are probably more plentiful right now, though.
Sorry, I don't have any info on sonic comparisons between the F5 and Aleph-X...
Eric
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I looked at the F4 and F5 on firstwatt.com and saw they both had the same power out.
Running single-ended stereo, yes.
I wrote that. 🙂 🙂 🙂 I'm working on one for the F4 as we speak.I focused on F5 since there was a builder's thread and seemed to be more info available for it.
Well, if you have a balanced preamp with about a 20v output swing, you can drive a pair (as monoblocks) of F4 to 100WPC. The disadvantage is that you are basically building a preamp specific to the needs of those power amps. The advantage is that you then have F4's, which practically everybody says are completely transparent sonically.Did it compare well with the F5? What's the advantage/disadvantage of balanced vs unbalanced?
Anyway, F4's aside, have you started collecting parts for your F5T build?
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