| F1, F2, F3 listening impression - Click HERE for Original Thread |
| Nicola |
I've been toying with F1, F2, F3 since about ten months (soon an elephant pregnency timing) in order to find out what best suits what. The setup : a 4 ways fostex horns driven system with a kliphshorn for the bass. A digital xover filter because it allows to set the phase and the delay compensation. Each Fs is therefore driving one driver.
Some smallish issues
F3 has 100uV noise which you can clearly hear with over 100db drivers. An LPAD helped to reduce the noise, thank you Mr Pass for the spec.
F1 has a slight thump up at turn on (80mV) which i don't like when driving tweeter, but anyway...
all have - I find - a small mecanical noise that relates to the of AC supply transformers (might change them in the future)
One F3 had an input badly screwed which did some miss contact (not a problem),
Listening rationale (oups somehow not logic here). Music is a matter of taste, of the type of music and the setup (devices and room), so my comments are nothing objective. I only tried to determine which amps would be best suited for which driver i.e frequency according to my tastes. So I swapped the Fs between the four drivers and listened and listened and and and....
In the end F1 appreared best suited for bass. It lacks nevertheless the headroom a voltage amps has. F1 is very precise and the amount of control is exercice on the driver is impressive. It is not sensitive to wire (have testes with 4mm2, 6mm2, OCOS with no differences) Nevertheless with some complex music (classics with organ or piano) it lack the depth and room in the bass region. I wondered if that is related to the little amount of power. F1 is not as fast and precise as F2 in the upper range. I found it a bit (a very small bit) bumpy in the mid range. So I settle for the bass although in some cases I would prefer a voltage amp. Compared to the voltage amp, the F1 is more precise (thus the impression of limited ?). In some instance I found it lacks the speed of conventional amps, that is what probably gives him a bit of a warmth in the lower bass which it rocks. It is not as fast / brutal bass amps as some voltage can be. Matter of taste again,
F3 are warm and a light colour effect on low / mid range (630 hz to 4300hz) especially for trumpet / saxo etc and chords instruments, very nice tube like amps. Nice, soft and delicate amps. Not very fast and brutal, not as precise over the control it has on the driver like the F1, F2 and a bit (but a bit only) bumpy in the bass (80hz). Instruments with lots of hamonics are well played, although the high end treeble are lacking the definition F2 provides. I settled for the mid range
F2, amazing for the high range (> 6300hz), hellacious fast, precise (cymbals are magnificient), and silent... There is a light coloring which appear more with some musics (vocal, opera, etc)
All in all the F3 are well suited for Jazz, blues and some classical music. The F1, F2 are a allroad stuff with some light weakness (i would dare to say) when it come to deep basses. Their precision is amazing in controling the driver. But their ruthless, if the source is (as unfortunately more and more) ****, you get the **** - it is the wysiwyg music version)
Voilà, anyway all three are very nice amps and worth listening. I enjoyed and enjoy reading the FirstWatt and DiYAudio and as many times mentionned by Mr Pass those amps are tinkerer amps, you have to allow time to play, try and play with it and enjoy the listening....
One additional thing, the FirsWatt reseller RenoHifi is very helpfull and efficient.
Regards |
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| Nelson Pass |
Thanks very much for the comments. Your experiences echo
mine to a large degree.
:cool: |
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| Nicola |
| quote: | Originally posted by Nelson Pass
Thanks very much for the comments. Your experiences echo mine to a large degree.
:cool: |
Thanks, actually I shall say the decision to adopt Fs was based on your work / contribution for the diy audio community, and A40 which i built as well as your approach to amps whic i qualify as a
blend of simple and elegant design.
I'd be curious what are the gaps in the "Your experiences echo
mine to a large degree." Where you would "not" agree.
I'd be interested in for the F4 - in due time of course ;-) |
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| Zen Mod |
| quote: | Originally posted by Nicola
I've been toying with F1, F2, F3 since about ten months............... |
you bought them all?
:D :clown: :) |
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| steenoe |
| quote: | Originally posted by Nicola
I'd be interested in for the F4 - in due time of course ;-) |
Ya better be!! Sell the others and invest in the F4 and a J-fet-BoZ
:D
Steen:cool: |
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| Babowana |
| quote: | Originally posted by steenoe
Ya better be!! Sell the others and invest in the F4 and a J-fet-BoZ
:D
Steen:cool:
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What is your time recycling record for beutiful girls oops :bigeyes: |
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| steenoe |
| quote: | Originally posted by Babowana
What is your time recycling record for beutiful girls oops :bigeyes: |
depending on their looks: from 3 months to eternety
The one I have got right now, is in the last category:D
Steen:) |
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| Zen Mod |
| quote: | Originally posted by steenoe
depending on their looks: from 3 months to eternety
The one I have got right now, is in the last category:D
Steen:) |
so-I'm not worst here.......or- re-frasing that - only one stacked for good :D |
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| Nelson Pass |
| quote: | Originally posted by Nicola
I'd be curious what are the gaps in the "Your experiences echo
mine to a large degree." Where you would "not" agree. |
I have not encountered the bumpy midrange in the F1, but then
I did not use horn loaded Fostexes (Fostices?)
:cool: |
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| Nicola |
| quote: | Originally posted by Nelson Pass
I have not encountered the bumpy midrange in the F1, but then
I did not use horn loaded Fostexes (Fostices?)
:cool: |
Indeed, I reckon / suspected it may come from the horn and the room which is not big enough unfortunately. I also noticed the choice of the xover did influence. With some devices the bump (although not a major nuisance) was more noticable. Horn are easily bumpy in those ranges i noticed, but i quite their sonic signature.
Moste likely with the Fs and given the room, what I may once would like to improve is to get rid of the transormer mecanical noise. Now I don't know what is best. Try to find a toroidal from a other make that is more silent, encapsulate the current toroidal in a shield ? What would you suggest ? Regards |
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| sklimek |
| quote: | Originally posted by Nicola
Now I don't know what is best. Try to find a toroidal from a other make that is more silent, encapsulate the current toroidal in a shield ? What would you suggest ? Regards |
| quote: | Originally posted by Nicola
all have - I find - a small mecanical noise that relates to the of AC supply transformers (might change them in the future)
Regards |
Hi, what transformer are you using? This is a timely thread for me as I am in the process of bi-amping with an Aleph30 and an F2. I have purchased two Antek's for the 30 but keep getting spooked by the Plitron vs. Antek debates for my other purchase. I have read both sides and respect the opinions of the ones who have weighed in for either transformer.
Would anyone out there care to do a torroidal shoot off? I am relatively new to diy and do not have the experience and set-up to perform it myself, I am aware that testing conditions would be subjective to the setup. I have a new Antek 20V/500VA transformer I would like to see it compared to a Plitron and could send to a willing tester, any other transformer could be used as well - A long shot I know, it would entail replacing the Plitron w/ the Antek and misc. for ‘buzz’ comparison and anything else w/ someone who is in that position for testing and has a similar Plitron or???
These transformers are expensive; the extra cost could be justified for a Plitron if in fact it is a better over-all performer.
Just a thot - Stan |
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| Nelson Pass |
| quote: | Originally posted by sklimek
I have purchased two Antek's for the 30 but keep getting spooked by the Plitron vs. Antek debates for my other purchase. |
The differences are probably not worth worrying about. I use
Plitron because we get consistent mechanical/electrical
performance. I have not even tried an Antek. If they want to
send me one, I will be happy to try it.
(Like all other things: transistors, wire, phono cartridges, and wine.
No additional women, thank you.)
:cool: |
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| sklimek |
| quote: | Originally posted by Nelson Pass
I have not even tried an Antek. If they want to
send me one, I will be happy to try it.
(Like all other things: transistors, wire, phono cartridges, and wine.
No additional women, thank you.)
:cool: |
Hi Nelson, yes I would love for you to have a look and to hear your thoughts! If you email me with your shipping address I'll send these two out to you or if you wish to deal w/ Antek instead I would talk to John Ango to see what his thoughts are, either way my pleasure!
ps I know you prefer red, I'll do some searching to see if I can dig up your preference...
Best - Stan |
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| Nelson Pass |
My shipping address is
Pass Labs
24449 Foresthill Rd
Foresthill CA 95631
:cool: |
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| sklimek |
Done!
Oh and Mr. Pass,
thankyouthankyouthankyouthankyouthankyouthankyou! |
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| Ryssen |
Just a liitle OT:I have heatsinks for a Mini-A Big ones,and I am in for the F3 pcb GB.
Any one compared the Mini-A against F3,I mean If I should change my mind and use those sinks for F3 instead...:blush: :c_flag: |
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| jupiterjune |
| quote: | | Just a liitle OT:I have heatsinks for a Mini-A Big ones,and I am in for the F3 pcb GB. |
I think giant heatsinks are overrated--my Mini Aleph had giant heatsinks, and I could leave it on all day and it never even got near British adjective hot. And it didn't quite have all the magic it was supposed to have--no change in sound after running for an hour or two...
So I rebuilt it with smaller heatsinks. When I first turn it on, it sounds as before, but after an hour, it gets blimeycreaky hot, and then -- the soundstage expands in all directions....voices turn to liquid -- all grain is completely disssolved -- trailing song reverberates from cathedral ceilings and I can see the up into the rafters of the church where the recording was made.....
or maybe that's just the Tanqeray kicking in....
But I will post some pix of the rebuilt Mini Aleph.
JJ |
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| mpmarino |
| quote: | Originally posted by jupiterjune
I think giant heatsinks are overrated--my Mini Aleph had giant heatsinks, and I could leave it on all day and it never even got near British adjective hot. And it didn't quite have all the magic it was supposed to have--no change in sound after running for an hour or two...
So I rebuilt it with smaller heatsinks. When I first turn it on, it sounds as before, but after an hour, it gets blimeycreaky hot, and then -- the soundstage expands in all directions....voices turn to liquid -- all grain is completely disssolved -- trailing song reverberates from cathedral ceilings and I can see the up into the rafters of the church where the recording was made.....
or maybe that's just the Tanqeray kicking in....
But I will post some pix of the rebuilt Mini Aleph.
JJ |
I don't think you're entirely imagining that. |
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| Ryssen |
| quote: | | I think giant heatsinks are overrated--my Mini Aleph had giant heatsinks, and I could leave it on all day and it never even got near British adjective hot. And it didn't quite have all the magic it was supposed to have--no change in sound after running for an hour or two... |
Nice it sounded better with smaller sinks.Wonder how it would sound with the big sinks and more bias,as i I was thinking of doing.And wonder how it sounds compared to F3?...:scratch2:
| quote: | | But I will post some pix of the rebuilt Mini Aleph. |
:nod: |
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| jupiterjune |
I put the first picture on a new thread--not to threadjack this one.
More pictures to follow, along with an explanation of the phase lag I saw in one channel......
JJ |
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| Nicola |
| quote: | Originally posted by jupiterjune
...it didn't quite have all the magic it was supposed to have--no change in sound after running for an hour or two... So I rebuilt it with smaller heatsinks. When I first turn it on, it sounds as before, but after an hour, it gets blimeycreaky hot, and then -- the soundstage expands in all directions....voices turn to liquid -- all grain is completely disssolved -- trailing song reverberates from cathedral ceilings and I can see the up into the rafters of the church where the recording was made..... |
Very interesting indeed, could someone explaine me how that is. Some how it is like saying that the transistor temperature has a impact on the sound. How is that ? I can understand that you need 1-2 hrs to warm up the amp so that currents and tensions are ok, but you mean something else. Somehow almost the hotter the best (I see some of you coming with joke...), until the melting point. |
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| Babowana |
| quote: | Originally posted by Nicola
Very interesting indeed, could someone explaine me how that is. Some how it is like saying that the transistor temperature has a impact on the sound. How is that ?
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I had similar experience as JJ had.
My current Babo Zen has heat sink temperature of about 23 - 28 degC above ambient on steady-state equilibrium which is depending on the ambient. The sound of the current Babo Zen is distinctively better than the old version which had lower heat sink temperatures on the same bias current condition.
I wondered myself too.
I looked into the data sheet of IRFP250N and saw that when the junction temperature goes up, the transimpedance goes down. This might explain it. I am unsure of it theoretically tho . . .
:darkside: |
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| Nelson Pass |
| quote: | Originally posted by Nicola
Very interesting indeed, could someone explaine me how that is. Some how it is like saying that the transistor temperature has a impact on the sound. How is that ? I can understand that you need 1-2 hrs to warm up the amp so that currents and tensions are ok, but you mean something else. |
The transconductance of the fets is higher at temperature, and
all the design and adjustment is at temperature.
:cool: |
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| Nicola |
| quote: | Originally posted by Nelson Pass
The transconductance of the fets is higher at temperature, and
all the design and adjustment is at temperature.
:cool: |
Does this mean that when you design a amp, the temperature come into the design ? Meaning to say you design the amps knowing that you expect if to reach this working temperature in order to provide best / more desirable sound ? |
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| Nicola |
| quote: | Originally posted by Nelson Pass
The differences are probably not worth worrying about. I use
Plitron because we get consistent mechanical/electrical
performance. I have not even tried an Antek.
:cool: |
To get rid of the small mecanical noise of the Fs transformer, what would you advise ? I wondered if they make this noise because Europ use 50Hz (instead of US 60hz) and 240V instead of 120V ? Easier would be to encapsulate / shield them in a iron can, but does that make sense ? Or is it best to replace with an other make looking for one, maybe a bit more powerfull and silent ? |
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| Nelson Pass |
| quote: | Originally posted by Nicola
Does this mean that when you design a amp, the temperature come into the design ? Meaning to say you design the amps knowing that you expect if to reach this working temperature in order to provide best / more desirable sound ? |
More or less. Usually the design takes advantage of higher
transconductance as the circuit is so simple, but in any case,
all the adjustments and tweaks are done at the presumed
operating temperture, typically an hour after warmup in a
23 deg C environment, with additional adjustment after another
hour or so, then burn in, and then slight adjustment once or
twice after that if needed.
| quote: | Originally posted by Nicola
To get rid of the small mecanical noise of the Fs transformer, what would you advise ? I wondered if they make this noise because Europ use 50Hz (instead of US 60hz) and 240V instead of 120V ? Easier would be to encapsulate / shield them in a iron can, but does that make sense ? Or is it best to replace with an other make looking for one, maybe a bit more powerfull and silent ? |
You can always reduce the AC voltage seen by the primary,
a coil being any easy way to do that. Low noise transformers
seem to be designed by slightly different rules than ordinary
ones, and one technique is to design the primary windings as
if the AC input voltage will be higher, in other words with more
turns on the windings.
:cool: |
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| vitalstates |
Hi Nicola
I've been following this thread but I'm still not sure if this is relevant.....but.....for my F2 I used one of the cheap clairtronics from rapid......Apart from some RF which I had to deal with, which is documented on the F2 thread, the transformer is totally silent.....
just my two penneth
Regards
Ed |
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| Nicola |
| quote: | Originally posted by Nelson Pass
You can always reduce the AC voltage seen by the primary,
a coil being any easy way to do that. Low noise transformers
seem to be designed by slightly different rules than ordinary
ones, and one technique is to design the primary windings as
if the AC input voltage will be higher, in other words with more
turns on the windings.
:cool: |
Most likely a stupid question, but how would you "reduce the AC voltage seen by the primary", by using a resitor I guess, but of how much ohms / wattage ? Will there be some effect on the amps ? I reckon the secondary will also proportionnaly be reduce; will that affect the performance of the amps ?Regards |
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| Nelson Pass |
| quote: | Originally posted by Nicola
how would you "reduce the AC voltage seen by the primary", by using a resitor I guess, but of how much ohms / wattage ? Will there be some effect on the amps ? I reckon the secondary will also proportionnaly be reduce; will that affect the performance of the amps ?Regards |
You can use a resistor, or an inductor, or a capacitor or some
combinations. Of course it will affect the secondary voltage,
and of course that will affect the performance. This is one of
those areas where it is best to experiment and see what works
for you.
:cool: |
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| Ryssen |
| Maybee Nelson has compared the Mini-A and F3`s sonic?:judge: :goodbad: :blush: |
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| Zen Mod |
| quote: | Originally posted by Ryssen
Maybee Nelson has compared the Mini-A and F3`s sonic?:judge: :goodbad: :blush: |
he made them .
:clown:
but - I have doubt that he made direct comparison |
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| sklimek |
OK, I just heard back from Mr. Pass and he mentioned that it was fine to forward his comments in regards to the Antek transformer and how it performed compared to the Plitron.
Here is the start thread for it:
http://www.diyaudio.com/forums/show...391#post1233391
And response:
> I received the transformer, and just finished playing with it a couple
> days ago. Very nice transformer with good regulation
> (5%) and good resistance to crappy AC lines.
>
> I didn't get a chance to evaluate it for noise, but I assume that the
> performance is good in that category.
>
> In any case, I can recommend it along with the Plitrons. This
> particular unit has more VA than the ones I'm using for FW.
>
> What is the cost?
> Thanks.
>
> best, np
He also mentioned that it’s worth the $51.00 for this 20 – 0 – 20 500VA Antek.
Once again, thank you for your valuable time it was very much appreciated.
Stan |
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| mpmarino |
| quote: | Originally posted by sklimek
OK, I just heard back from Mr. Pass and he mentioned that it was fine to forward his comments in regards to the Antek transformer ......................................... |
That's really cool to shed a bit of light on this !
Thanks Stan and Mr. Pass.
| quote: | Originally posted by Zen Mod
...........................
but - I have doubt that he made direct comparison |
Hmmm, how would you know?
Are you Robin Masters? Is Oly Robin Masters? I'm getting suspicious.
:clown: |
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| Zen Mod |
| quote: | Originally posted by mpmarino
......
Hmmm, how would you know?
Are you Robin Masters? Is Oly Robin Masters? I'm getting suspicious.
:clown: |
who's Robin Masters?
I'm bloody Serb and I dunno who's that ............ :clown:
ps. when someone have that mileage under own bu** ,somehow I doubt he have need for direct comparisons...... :devilr:
if it sings,then it sings ..........
( ya know that I have secret connection in Pass Labs :clown: )
edit:
crazy yankee
http://en.wikipedia.org/wiki/Robin_Masters |
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| Nicola |
while listening if have the odd impression the F2 is doing strange thing, like tensions varies after 1 hour of running. I thought o measure tensions and looked on the firstwatt for the SRV-OManual hoping there would be in the schematic some indication of what are the normal voltage. I found the schematic but it holds no indication unlike for example the F1 or F3. Would Mr Pass or anybody know a document where i could find these indications ?
Kind regards |
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| Nelson Pass |
| quote: | Originally posted by Nicola
looked on the firstwatt for the SRV-OManual hoping there would be in the schematic some indication of what are the normal voltage. I found the schematic but it holds no indication |
The voltage on the Drains of the Mosfets should be 1/2 the
power supply plus 1 volt after 1 hour operation.
:cool: |
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| vitalstates |
Ahhh so
Confuscious, he say...F2 like game of mornington crescent... |
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