First Watt F5 vs Aleph 5 - Page 2 - diyAudio
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Old 19th February 2010, 02:22 PM   #11
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Quote:
Originally Posted by VladimirK View Post
In Aleph topologies, "rounded sound" could result from a single electrolytic, standing at important point of schematics. Using BG or Elna Cerafines could make Aleph sound as detailed as F5, but with a bit tuby character.
The A5 caps are by-passed, and "very expensive at $80 each" caps were used in the power supply. The A5 also used ultra-fast rectifiers and a bunch other nice tweeks. A5 still has that smooth tube sound w/ weight. Says a lot about the topologies involved: SE vs P-P.

In my opinion, maybe if it were an A5J, it could grab more detail, like the F5.
The F5 is just a fast amp.
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Old 19th February 2010, 05:32 PM   #12
joho is offline joho  Netherlands
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Default Damping factor

Edit:
Also, I didn't hear that the bass was less powerful with the F5 because of less power.
I feel it is tighter. I listened on 89 db sens. speakers that stayed around 8 ohms.
[/QUOTE]

A few weeks ago I measured the damping factor of different Pass designs.
The test frequency and load was 50hz/6 ohm. Results:

Aleph5 around 25
AX (4 fets 30Watt each) around 20
F5 around 40
BA2 (6 fets a channel 20 watt each)around 40

So it's logical the F5 is tighter at the low end than the A5.
But less powerfull? I.M.H.O no.

At the moment I'm comparing a AX with the F5.

Gr.
Johan
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Old 19th February 2010, 05:43 PM   #13
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Quote:
So it's logical the F5 is tighter at the low end than the A5.
But less powerfull? I.M.H.O no.

Gr.
Johan
Yes, more control is another way to put it.
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Old 20th February 2010, 12:37 AM   #14
alazira is offline alazira  United States
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Quote:
Originally Posted by Nelson Pass from a review on Lowther Alerions
The Alerions bass response seems to prefer amplifier output impedances in the region of about 1 ohm or so, for a damping factor of about 8. Less than this, and the bottom end gets a little bloated, more than this, and it starts to lose some life.
Hi Nelson,

Would it be fair to say that each driver has a damping factor "sweet spot" for bass response?
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Old 20th February 2010, 12:44 AM   #15
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally Posted by alazira View Post
Hi Nelson,

Would it be fair to say that each driver has a damping factor "sweet spot" for bass response?
take that as driver/enclosure combo ;

matter of construction approach - with some you count on DF/series resistance influence on overall Q factor , with some you dismiss that influence
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Old 20th February 2010, 12:53 AM   #16
Rony1 is offline Rony1  United States
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Quote:
Originally Posted by vdi_nenna View Post
I have heard both of them in one day. Both DIY projects.
The A5 is sweeter and has a more rounded sound. The F5 is more defined.
Both are very good, but at a minimum, they are different in sound character.

It's going to come down to what you like best with your associated equipment. Can't lose.

Edit:
Also, I didn't hear that the bass was less powerful with the F5 because of less power.
I feel it is tighter. I listened on 89 db sens. speakers that stayed around 8 ohms.
Are your speakers easy to drive?
My current speakers have sensitivity of ~86 dB ~4 Ohms. Interesting what you say about the bass, I found out that many things could influence bass tightness, for example,

My modified Shanling CD-T80 had "more" bass with original Op-Amps, with the new ones the bass seemed to be a little lower, but in actuality it was tighter.

Same thing when I added a new preamp, more bass but not as tight.

Thanks for the information guys.
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Old 4th March 2010, 10:27 AM   #17
galop is offline galop  Slovenia
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I make both F5 and A5. F5 is wery pleasant for ears ,fast and deep bass,very open sound,
A5 is more smooth,very detailed and has more dinamic and power than F5.Both good amplifiers.I have one problem with A5 with crc PSU.when i turn it on i have big thump on loudspeakers,about 6 v DC.what do you suggest?

this is aleph 5 ,but is not finished yet.
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Old 4th March 2010, 11:03 AM   #18
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I would propose, when one compare or characterize different amps, to add some info about their practical use. Just for instance, like " I prefer A5 for jazz, but F5 for rock" etc. If possible, of course. I am sure this would help to better understand different sound characters.
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Old 4th March 2010, 11:30 AM   #19
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Galop,
i would not fit the bridges on the main heatsinks, which vill run them uselessly warm. The bottom plate is a better place, imo.
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Old 4th March 2010, 12:07 PM   #20
galop is offline galop  Slovenia
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Thank you,i will put bridges on bottom plate when will replace PSU resistors with coils,because bottom plate is even hotter.Hm i think the aleph 5 is better ,after listening about 5 hours of jazz and acoustic music on A5 i plug back F5 and sound become less detailed and open,more flat,maybe because of my loudspeakers.Dont understand me wrong,F5 still sound superb, but A5 is sounds better on my speakers.
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