Power amp question

[Plott]

Hi,
I would like to ask you a question, also at the risk of it being a stupid question
After almost 30 years of doing nothing, now I've finished my two ACAs. And they are great. But - the diy-fever is here and I want more. One thing is certain: the next project must be another Pass power amp... but which one 😕 So here it comes, the stupid question: is there a "ranking" of the power amps? Is an F6 better than an F5 better than an Aleph J better than an M2x... and so on? They are all great, but are they only different at the same high level of the sound quality (what comes first for me)?
Thank you for your help in making a decision 🙂

Cheers

 

[Zen Mod]

they're all great

say more about room, speakers, SPL habits

that way we can differentiate best candidates for your needs

 

[wwwtttwww]

You need to build all of them to find out which is the best for you.

No one will tell you Pass F-x better than F-y better than F-z better than F-a.

For me, F4 is better than F5 better than all other F-xxx( since I build only F4 and F5)

 

[Plott]

Thanks @ZM!
My living room has about 30 sqm / 323 sq ft, my current speakers are the Sonus Faber Venere 2.5 and the Frugel Horn MkIII; now I am working on the MLTL with B80 & RS225-8 by xrk. I can meet my volume needs with the ACA too, so SPL is not really a factor.

"You need to build all of them to find out which is the best for you." Yes, that is exactly my fear 😀

 

[myleftear]

Sound of various Pass amps

 

[Plott]

Wow, thanks a lot, that's exactly what I was looking for 🙂

 

[myleftear]

Yes but still listen to / ask ZM.

 

[Plott]

For sure, I'm waiting for his reply 🙂
In the meantime, I also found his Babelfish, in the latest reincarnation... makes things not easier 😀

 

[andynor]

To turn your question around a bit, if not 100%, you are basically asking the worng question. There is no such thing as the perfect amplifier, ref Papa and therefore logic. But there is such a thing as the best amplifier - for you, and for your speakers. So it boils down to what ZM asks aboutf what speakers are they to drive in which room, and what is your desired sound signature and SPLs.

For example, for Fabers, I would go push-pull to start with, then find the Push-pull amp that matches my preferences wrt harmonics/sound signature, and then verify this choice matches preamp wrt gain structure.

There is no need to build them all to know where to start. Manuals provide enough juice to start narrowing the search.

For fabers, maybe BA-3 with BA-2 OS could be for you. Natural, extremely dynamic and punchy. Or F5 or F5T, if you like truth machines with a preference for blowing up if you make a mistake. Or M2x, maybe?

Choice is yours, advice will get you along the way, but in the end - as with everything - it is a choice where you almost always must compromise somewhere. Thing is to find your ideal combination of compromises 🙂 If pure sound and class A bliss is your target, single ended class A might be for you. If high SPL and tough to drive speakers are your thing, I’d not opt for anything but push pull or XA-style SE.

Regards,
Andy

 

[Zen Mod]

......I can meet my volume needs with the ACA too, so SPL is not really a factor. ........

this is most important fact in this moment, from which you can build your strategy

easiest and most fun is certainly Best Ever FW amp - M2

Boyz are building it with all sorts of FE iterations, but original one is hard to beat in versatility and fun factor

my own iteration of M2 (Babelfished) is different in different way, but that's whole other story

if you want to build an amp capable to drive both ends of scale ( efficient and not so efficient spks you have), then think ......... you need mini welding machine to cope with 'Talian Beauties

(which I like, but despise price and fairy tales )

 

[andynor]

Welding machines like this is perfect match for your mini Lamborghinis: Babelfish XJ , or JX …….. or whatever – Zen Mod Blog

 

[Plott]

Thank you very much Andy and ZM!

"For fabers, maybe BA-3 with BA-2 OS could be for you. Natural, extremely dynamic and punchy. Or F5 or F5T, if you like truth machines with a preference for blowing up if you make a mistake. Or M2x, maybe?"

Yes, exactly 😀

"easiest and most fun is certainly Best Ever FW amp - M2"

The M2(x) was also my first thought, along with the Aleph J.

But I think it's almost impossible not to build many of this amps... Great 🙂

 

[xrk971]

Hi Istvan,
If you want to drive the 10F(B80)/RS225 FAST speakers, they need some power (40w minimum). So typical 25w FW Class A amps may not be enough. So you might look at higher power variants of Pass amps. There are also other Class A amps that make 40w or more available, not designed by Mr Pass.

OTOH, Vunce has the same speakers and loves how they work with the DIY lottery VFET amp. So YMMV. I think it helps if the amp clips gracefully (basically a built in compressor).

Good luck in your selection.

 

[Plott]

Hi xrk,

thank you very much, 40w minimum for the FAST is of course another important argument. So I should make a plan... will see 🙂

 

[andynor]

BA-3/BA-2 @32v rails=40w 🙂

 

[MEGA_amp]

SOZ....the 50W version of course😀

 

[Plott]

Andy, MEGA, thank you both 😀
I will do it step by step. The first will be a BA-3 or an M2x and as an alternative I will check the Alpha Nirvana too. Then I have to build a very good and appropriate preamp.

 

[myleftear]

Depending on what output-stage you choose, you may consider salas‘ dcg3 pre: Salas DCG3 preamp (line & headphone)

Highly regarded!

 

[Plott]

Thanks a lot myleftear! Things getting better and better🙂

(One thing: it is just great how much help I get in this forum, thank you all 🙂 )

 

[Zen Mod]

as usual, if you live through cacophony in start, you'll be properly helped