Long story short,
(I never menage to keep it short...), I have a vintage system with AR SP9, Sony ES505, Gyrodec, JBL L220 (90dbW/m) and push pull of KT88 (also an Adcom GFA 535 which is undergoing restoration and upgrades), small listening space, 90s rock, house, some jazz, little little classic... it sounds pretty nicely with my kind of music, I like the tubes vs SS but to keep entertained during these weird times I asked a friend, who's got a true audiophile system (he listens with Sonus Faber Electa bi-amped with twin mono Red Rose power amps...) what about a DIY little power amp with, say, 20-30W and he said, with no hesitation, "Pass First Watt".
Questions:
- would such an amp suffice demand of 90db speakers as by above specs?
- is it something easy to build provided one can retrieve kits/parts and can handle a soldering iron and a multimeter?
- is price/quality ratio favourable vs a commercial product?
- enough current to drive the big JBL woofers?
Suggestions and hints very welcome
Thank you for your patience
Giovanni
(I never menage to keep it short...), I have a vintage system with AR SP9, Sony ES505, Gyrodec, JBL L220 (90dbW/m) and push pull of KT88 (also an Adcom GFA 535 which is undergoing restoration and upgrades), small listening space, 90s rock, house, some jazz, little little classic... it sounds pretty nicely with my kind of music, I like the tubes vs SS but to keep entertained during these weird times I asked a friend, who's got a true audiophile system (he listens with Sonus Faber Electa bi-amped with twin mono Red Rose power amps...) what about a DIY little power amp with, say, 20-30W and he said, with no hesitation, "Pass First Watt".
Questions:
- would such an amp suffice demand of 90db speakers as by above specs?
- is it something easy to build provided one can retrieve kits/parts and can handle a soldering iron and a multimeter?
- is price/quality ratio favourable vs a commercial product?
- enough current to drive the big JBL woofers?
Suggestions and hints very welcome
Thank you for your patience
Giovanni
It looks like your speakers (8ohm/90db) would be a good fit for most of the FW amps. If you prefer the sound of tubes, the Aleph J (as Bones mentioned) would be a good fit. I’d also consider an F6. It’s a simple build and available as a parts kit in the store. It’ll be hard to go wrong though.
agree on that
though , regarding M2 - besides being best and most funny amp (in Entire Universe and Beyond), from practical side - it is nothin more and nothing less than - F4 for us lazy and clueless bstrdz
Hi Giovanni,
If it helps at all I’ve got a pair of JBL L150’s rated at 88/89 db (12” 128H woofers with 3” voice coils). My listening space is 14’ wide x 25’ long with 8’ ceilings, and my listening position is approx 12’ away from the speakers. I’ve been powering them in rotation with the Aleph J and the M2x for a few years now and it is plenty loud for me.
I am so very new to this thing, starting off the needs which are the speakers with 90db efficiency, big coils to move and music I like to listen and a preference for warmer than SS sound of tubes, 25W could make it to begin with and if easy, affordable and good to my (not so trained) ears might then go for a second one to use both in mono as to have enough juice for the big California speakers and make my freak system friend enjoy some A class on the cheap ;-)
What about the F5?
I found parts here on the shop, still have to figure the parts list, as far as I understand I can get PCBs, resistors, FETs and that's it, transformer and case (with pre drilled holes) are on the side, am I correct with this?
So far it seems the cases are made in Italy (and expensive!!!), it would be an advantage for me since that's where I live.
What about transformers?
Final price of the whole assembly for, say, the F5?
You all very kind and quick into reply, it feels like this is a nice community, thanks for your warm welcome
Giovanni
What about the F5?
I found parts here on the shop, still have to figure the parts list, as far as I understand I can get PCBs, resistors, FETs and that's it, transformer and case (with pre drilled holes) are on the side, am I correct with this?
So far it seems the cases are made in Italy (and expensive!!!), it would be an advantage for me since that's where I live.
What about transformers?
Final price of the whole assembly for, say, the F5?
You all very kind and quick into reply, it feels like this is a nice community, thanks for your warm welcome
Giovanni
Oh, didn't read this before my reply, good to hear so.
I will take a pic of my actual listening (messy) space, very small, feet wise speakers are less than 5' apart, walls about 2' feet on the sides and little less on the back (speakers can be moved forward if needed cause they stand on horrible geared plates which I want to rearrange), listening point about 5-6' and no obstacles behind; I am looking to rearrange it all into adjacent room where there will be constraint with almost no side space but here where I live space is precious and I have to make virtue out of necessity (or buy myself fancy Italian speakers
).With my push pull KT88 delivering about 50W I never twist the volume knob higher than hour 11 on my Audio Research SP9 preamp so 25W could suffice and if, as said above, price and sound wise convincing, besides being able to build and make it work, a twin would be nice and filling my dream of mono blocks to power the babies.
Grazie
Giovanni
in greater scheme of things - Modushop cases are cheap, believe me (or not - just look at prices of heatsink, then bare aluminium plate for front, then cheapest Fe sheets, add fabricating expenses for all elements to get them from rough dimension to proper form, then anodising & powdercoating .......)
everything else .... whichever FW amp you choose to make, take in account that cheapest original was , what, around 3K$?
and that, as damn great bang for the buck
goal is - to make great amp for cheap, having enormous joy (even if some tremble, 'cause you're Greenhorn) while making it
if you build, build proper - or don't build at all......... spare some and buy second hand fancy 'Talian amp (everyone speeding to get rid off )
- with some luck, you can collect all parts for 600-700E
-I adore 'Talians, driving 'Talian car and bike ...... so having soo much fun speaking of products beneath great 'Talian engineering history
everything else .... whichever FW amp you choose to make, take in account that cheapest original was , what, around 3K$?
and that, as damn great bang for the buck
goal is - to make great amp for cheap, having enormous joy (even if some tremble, 'cause you're Greenhorn) while making it
if you build, build proper - or don't build at all......... spare some and buy second hand fancy 'Talian amp (everyone speeding to get rid off )
- with some luck, you can collect all parts for 600-700E
-I adore 'Talians, driving 'Talian car and bike ...... so having soo much fun speaking of products beneath great 'Talian engineering history
Giovanni,
Since you're in Europe, I suggest looking into Toroidy transformers as they are
highly regarded.
Power transformers - Internet shop Toroidy.pl
These amps are not the cheapest to build since class A requires
big hardware, but I think they are absolutely worth it. Remember
these are highly regarded commercial designs that Papa has allowed
us to build for personal use. These are gifts to the DIY community.
Probably 80% of your cost will be in the chassis/heatsinks/power transformer/PSU,
the big hardware. The amp boards and parts make up only a small
portion of the cost. Note also that many of these amps
(for example: M2, AJ, F4, F5, F6) can be built on the same 'platform'.
Should you want to try a different design down the road, you just build
a new amp board and hook it up; the rest can stay the same.
With some care, a lot of members have successfully built these amps
with basic tools and without much prior experience.
I use 89dB speakers and am also in a small space. All my FW builds
have worked well.
Dennis
Since you're in Europe, I suggest looking into Toroidy transformers as they are
highly regarded.
Power transformers - Internet shop Toroidy.pl
These amps are not the cheapest to build since class A requires
big hardware, but I think they are absolutely worth it. Remember
these are highly regarded commercial designs that Papa has allowed
us to build for personal use. These are gifts to the DIY community.
Probably 80% of your cost will be in the chassis/heatsinks/power transformer/PSU,
the big hardware. The amp boards and parts make up only a small
portion of the cost. Note also that many of these amps
(for example: M2, AJ, F4, F5, F6) can be built on the same 'platform'.
Should you want to try a different design down the road, you just build
a new amp board and hook it up; the rest can stay the same.
With some care, a lot of members have successfully built these amps
with basic tools and without much prior experience.
I use 89dB speakers and am also in a small space. All my FW builds
have worked well.
Dennis
Hello,
I did read about the F5 and watched a video split into 4 parts about the build of an F6 if I recall correct, very interesting, not for a beginner but there is lot of info out there to look up for just in case.
Somebody here in Italy, on a local forum, says the FW lack a little on the low end, what's your opinion?
To get an idea, would you tell me the parts list so I can find out an approx final price?
I heard about the Polish transformers company, also about the Italian one for the case, I know they will account for most of the cost along with the PSU but to make up my mind if it fits in a mid term budget (I sold an unused tonearm and have a few hundred at this moment to dedicate to this project eventually).
Grazie e buon fine settimana everybody
Giovanni
I did read about the F5 and watched a video split into 4 parts about the build of an F6 if I recall correct, very interesting, not for a beginner but there is lot of info out there to look up for just in case.
Somebody here in Italy, on a local forum, says the FW lack a little on the low end, what's your opinion?
To get an idea, would you tell me the parts list so I can find out an approx final price?
I heard about the Polish transformers company, also about the Italian one for the case, I know they will account for most of the cost along with the PSU but to make up my mind if it fits in a mid term budget (I sold an unused tonearm and have a few hundred at this moment to dedicate to this project eventually).
Grazie e buon fine settimana everybody
Giovanni
that can't be said for any proper amplifier of this world, without proper context
and you can believe us , that FW amps are proper
another thing - I would choose as first project, an amp which doesn't need any other setting procedure than basic one - setting output DC Offset and Iq (standing current)
F5 is of those amps for which, to end with best and controlled results, one needs more knowledge and some equipment , to set THD Spectra by own liking
considering that, I would go with either M2 or Aleph J, for your speakers - minimal settings needed, pretty much controlled results regarding THD Spectra........ while F5 could end on both ends of spectrum, being either bright or mellow, so to speak
I have an F6 with strong power supply with plenty of low end , this guy may havent listen an FW amp
how much is "few" , if it's 10 it's almost ok , if it's 5 , you'd better wait a moment
.
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With regards to build aContenitorind tweak I can count on an expert friend even tho he is 18NM across.
Considering my speakers, the L220 which are 90dbW/m and my preamp being the SP9, and cost constraints where would you land?
My dream would be to later on build a second one to have two monoblocks.
Would you kindly give me the specs for the transformer(s) so I can check the Polish made ones prices?
Also, case wise, what's the maker and model to fit the Fx amps?
Having a good week end?
Edit: HiFi 2000 is the case maker, looking at them
Considering my speakers, the L220 which are 90dbW/m and my preamp being the SP9, and cost constraints where would you land?
My dream would be to later on build a second one to have two monoblocks.
Would you kindly give me the specs for the transformer(s) so I can check the Polish made ones prices?
Also, case wise, what's the maker and model to fit the Fx amps?
Having a good week end?
Edit: HiFi 2000 is the case maker, looking at them
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