Hello everybody,
simple question, I almost made up my mind at trying the route towards a FW F4 as suggested by many, I am now listening to tubes which I like but I'd like to try a very good SolidState without breaking the bank and a friend came up with the FW suggestion.
I know it sounds like a silly question but which is the real advantage of two mono blocks vs a stereo one?
Is it just (...) about power or what?
I understand costs are way higher, not double but almost, two cases, two transformers (even if smaller), twice capacitors... and twice the space but since there is no wife to complain who cares...
Just curious
Have a nice day
Giovanni
simple question, I almost made up my mind at trying the route towards a FW F4 as suggested by many, I am now listening to tubes which I like but I'd like to try a very good SolidState without breaking the bank and a friend came up with the FW suggestion.
I know it sounds like a silly question but which is the real advantage of two mono blocks vs a stereo one?
Is it just (...) about power or what?
I understand costs are way higher, not double but almost, two cases, two transformers (even if smaller), twice capacitors... and twice the space but since there is no wife to complain who cares...
Just curious
Have a nice day
Giovanni
Ciao Giovanni,
On a few occasions, I could compare stereo amps with monos, and despite cost, choose monos. Especially if the mono amp is really balanced, I could hear better control and better 3-D soundstage. I even built a balanced filter for my speakers, although many might think I´m crazy...
Good luck with your project!
Saluti
Mattes
On a few occasions, I could compare stereo amps with monos, and despite cost, choose monos. Especially if the mono amp is really balanced, I could hear better control and better 3-D soundstage. I even built a balanced filter for my speakers, although many might think I´m crazy...
Good luck with your project!
Saluti
Mattes
If in doubt, build a dual mono stereo amp.
There is not much gain in building mono blocks VS dual mono stereo amp unless heat dissipation and/or chassis space is a concern.
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Same here. Whether the added expense and effort are justified is a personal decision and a first hand experience is essential. Very hard to tell if money spent on better parts is not wiser. When in doubt, do both🙂
And of course there is the issue of mass and size. I can no longer lift or service decent stereoamps but can still just about manage monoblocks.
Giovanni1968:
I've built both monoblock and dual mono amplifiers and prefer either over similar stereo amps. I also agree with AudioSan: if heat dissipation or power demands require it, go for monoblocks. Otherwise, dual mono will be your best option.
Regards,
Scott
I've built both monoblock and dual mono amplifiers and prefer either over similar stereo amps. I also agree with AudioSan: if heat dissipation or power demands require it, go for monoblocks. Otherwise, dual mono will be your best option.
Regards,
Scott
Ok,
dual mono makes sense with no big heat dissipation needs, I mean, if the project fits and works into a 4U case then that's not the concern.
I guess the separate boxes is both heat dissipation and ego 🙂
What would be the practical difference at building something like the F4 in stereo or dual mono, just splitting the transformers and power boards for each channel?
I have a friend who is supposed to come off the US to Italy and might ask him to get me the boards so that I can start and think about the shopping list, just wondering which is the best and easiest solution.
Grazie
dual mono makes sense with no big heat dissipation needs, I mean, if the project fits and works into a 4U case then that's not the concern.
I guess the separate boxes is both heat dissipation and ego 🙂
What would be the practical difference at building something like the F4 in stereo or dual mono, just splitting the transformers and power boards for each channel?
I have a friend who is supposed to come off the US to Italy and might ask him to get me the boards so that I can start and think about the shopping list, just wondering which is the best and easiest solution.
Grazie
Stereo amp ex: 1pc 400VA transformer, 2 rectifiers, 8x15.000uF cap bank.
Dual mono ex: 2pc 200VA transformer, 4 rectifiers, 2pc 6x10.000uF cap bank. (caps are priced by the uF)
So twice the transformers, but smaller. Twice the rectifiers. Same total cap bank. So the price difference would not be huge.
Dual mono ex: 2pc 200VA transformer, 4 rectifiers, 2pc 6x10.000uF cap bank. (caps are priced by the uF)
So twice the transformers, but smaller. Twice the rectifiers. Same total cap bank. So the price difference would not be huge.
Having separate power supplies for each channel makes a noticeable and overall improvement to the sound of the amplifier. Whether this is done as dual-mono in a single chassis or in separate chassis to make monoblocks is up to the builder. Some amps, due to their sheer size (eg. BA-3) need separate chassis for each channel.
Hello again,
so, cost wise it will sure be more expensive but not to a big degree if I got it right, concern being would it be more difficult to assemble the whole thing?
With regards to the boards and other stuff on the DIY store:
- clone boards
- power supply boards
Mosfets, Jfets, caps, transformers, resistors, diodes and case can easily find either in Italy or in the EU, are the boards all I mandatory need to get off the store to go ahead?
Grazie ancora
so, cost wise it will sure be more expensive but not to a big degree if I got it right, concern being would it be more difficult to assemble the whole thing?
With regards to the boards and other stuff on the DIY store:
- clone boards
- power supply boards
Mosfets, Jfets, caps, transformers, resistors, diodes and case can easily find either in Italy or in the EU, are the boards all I mandatory need to get off the store to go ahead?
Grazie ancora
Monoblocks gives you more room inside a chassis, which allows for better placement of PCB’s and sporter wiring.
The advantages of dual mono has been mentioned above. One other thing which can lead to some frustration with a stereo enclosure, is hum due to possible groundloops.
But, as for many DIY’ers; chassis building is not the most pleasant work. I have found a rather easy way for myself.
Enclosures below are 440mm (W) x 420mm(D) x 210mm(H).
https://www.diyaudio.com/forums/sol...low-nfb-fet-front-bjt-ops-15.html#post6249192
The advantages of dual mono has been mentioned above. One other thing which can lead to some frustration with a stereo enclosure, is hum due to possible groundloops.
But, as for many DIY’ers; chassis building is not the most pleasant work. I have found a rather easy way for myself.
Enclosures below are 440mm (W) x 420mm(D) x 210mm(H).
https://www.diyaudio.com/forums/sol...low-nfb-fet-front-bjt-ops-15.html#post6249192
You mentioned a 4U chassis. you can fit 4ch, 4 transformers and 4 universal PSU boards inside a 4U 400mm chassis (it would be tight, but i would fit).
3U400mm chassis would be a nice fit for a dual mono F4. As long as the dissipation is not too high.
I for one like a tight fit. i can't stand looking into a "emty" chassis 🙂
Here is a 5ch amp i build almost 2 years ago. That is a realy tight fit.
The chassis was build with a 4U modushop front and 5 pc 4U300mm sinks. Internal depth is 500mm.
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Good morning from Italí,
ok, dual mono makes sense, little bit more expensive but less hassle because of possible ground loops.
I also understand the recommended 4U not being necessary even in case of fitting a dual mono as pictures above are self explanatory and I am on the same idea, I like having room to comfortably move but don't like empty spaces, once dissipation is enough and space to fit two transformers as well I won't like to have a huge empty box also because here space is very tight.
So, buying list wise, which are the mandatory items I better get off the DIY store, just boards?
Grazie e buona giornata
Giovanni
ok, dual mono makes sense, little bit more expensive but less hassle because of possible ground loops.
I also understand the recommended 4U not being necessary even in case of fitting a dual mono as pictures above are self explanatory and I am on the same idea, I like having room to comfortably move but don't like empty spaces, once dissipation is enough and space to fit two transformers as well I won't like to have a huge empty box also because here space is very tight.
So, buying list wise, which are the mandatory items I better get off the DIY store, just boards?
Grazie e buona giornata
Giovanni
Giovanni1968:
I suggest the 4U / 400mm chassis from Modushop/HiFi2000. With 4U, it is possible to stack the power supply pcbs on top of the toroids, leaving lots of open space for ventilation. 400mm depth gives you plenty of space. Also, I'd use larger power supply capacitors than those recommended by AudioSan: for the F6, I'd suggest using eight 12k uF caps per power supply board. In my opinion, the extra capacitance provides a little more authority and depth without adding any noticeable bloat. Finally, unless you are comfortable drilling and tapping threaded holes in aluminum, have HiFi2000 do it for you in accordance with diyAudio's UMS pattern; it isn't a standard option for the 4U/400mm Dissipante chassis, but they offer it as an additional service. Well worth the expense.
I've attached a couple interior photos of my dual mono F6.
Good luck with your project!
Regards,
Scott
I suggest the 4U / 400mm chassis from Modushop/HiFi2000. With 4U, it is possible to stack the power supply pcbs on top of the toroids, leaving lots of open space for ventilation. 400mm depth gives you plenty of space. Also, I'd use larger power supply capacitors than those recommended by AudioSan: for the F6, I'd suggest using eight 12k uF caps per power supply board. In my opinion, the extra capacitance provides a little more authority and depth without adding any noticeable bloat. Finally, unless you are comfortable drilling and tapping threaded holes in aluminum, have HiFi2000 do it for you in accordance with diyAudio's UMS pattern; it isn't a standard option for the 4U/400mm Dissipante chassis, but they offer it as an additional service. Well worth the expense.
I've attached a couple interior photos of my dual mono F6.
Good luck with your project!
Regards,
Scott
Attachments
SRMcGee. those was not recomanditions, but examples of the difference between stereo and dual mono 🙂
One can use a little larger caps. but don't overdo it without uping the transformer VA too.
One can use a little larger caps. but don't overdo it without uping the transformer VA too.
i'd sure ask the case producer to pre drill the holes on the cooling panels to fit the MosFets and also the pre drilled back panel, will then check with them for that, I see that also the base plate with holes in an extra and at the end the cost of the 4U will end in the 250 range more or less.
Since the amp will then sit on a shelf I'd prefer to have right size rather than plenty of room, in this instance height, if transformers can fit next to each other rather than on top I'd go for a smaller one like a 3U if it meets the cooling requirements, however nice these cases might be they would still look like a hotel fridge when on a shelf...
Shopping list wise whilst boards (both power amp and power supply) are available as well as JFets the Mosfets aren't but I guess no big deal as they can be found in matched pairs even here in Italy/EU
Oh, @McGee, the plan is for an F4, if I go for the dual mono route and wanna have enough juice in case of future upgrades and raise the transformer from, say, 2x200VA to 2x300VA still recommended to also raise caps total value and, if so, to which degree and, finally, would it have a meaning or just an ego thing to see bigger things inside there?
Grazie ancora, you all are very patient with a nerd like me...
Giovanni
Since the amp will then sit on a shelf I'd prefer to have right size rather than plenty of room, in this instance height, if transformers can fit next to each other rather than on top I'd go for a smaller one like a 3U if it meets the cooling requirements, however nice these cases might be they would still look like a hotel fridge when on a shelf...
Shopping list wise whilst boards (both power amp and power supply) are available as well as JFets the Mosfets aren't but I guess no big deal as they can be found in matched pairs even here in Italy/EU
Oh, @McGee, the plan is for an F4, if I go for the dual mono route and wanna have enough juice in case of future upgrades and raise the transformer from, say, 2x200VA to 2x300VA still recommended to also raise caps total value and, if so, to which degree and, finally, would it have a meaning or just an ego thing to see bigger things inside there?
Grazie ancora, you all are very patient with a nerd like me...
Giovanni
A 3U400mm chassis should do the job. 2x300VA transformer and 16x15.000uf 35V caps.
Transformers side by side in the front of the chassis and the PSU boards side by side in the back of the chassis. Raise the PSU boards 50mm from the bottom and you got room for softstart, DC protection and a smal transformer for it under the PSU boards.
you need to break of the rectifier part of the PSU to get room for it. Place those boards under the PSU, or use brick rectifiers.
Transformers side by side in the front of the chassis and the PSU boards side by side in the back of the chassis. Raise the PSU boards 50mm from the bottom and you got room for softstart, DC protection and a smal transformer for it under the PSU boards.
you need to break of the rectifier part of the PSU to get room for it. Place those boards under the PSU, or use brick rectifiers.
Which characteristics should the caps have to suit such a project so that I can lookup on an online catalogue and figure total cost of the build?
Same question about transformers, if I recall correct they should have +- 18V outputs, either 1x400/500VA or 2x200/300VA (still if I recall correct off the project of the F4).
Chassis wise at the end it's not just a matter of costs because once you get the holed base plate, the back panel with pre drilled holes for posts, switch etc and pre drilled holes for the MosFets the difference between a 3U and a 4U is matter of 20-30 euros probably but space wise, given I won't keep in in a rack due to lack of ventilation but rather on top of a (horrible Ikea) piece of furniture till some day I am able to get a nice and simple shelf, matter of height.
Buona domenica!
Same question about transformers, if I recall correct they should have +- 18V outputs, either 1x400/500VA or 2x200/300VA (still if I recall correct off the project of the F4).
Chassis wise at the end it's not just a matter of costs because once you get the holed base plate, the back panel with pre drilled holes for posts, switch etc and pre drilled holes for the MosFets the difference between a 3U and a 4U is matter of 20-30 euros probably but space wise, given I won't keep in in a rack due to lack of ventilation but rather on top of a (horrible Ikea) piece of furniture till some day I am able to get a nice and simple shelf, matter of height.
Buona domenica!