Gentlemen, can you please recommend outputs that are
-"european" type
-T0220 or similar
-32VDC rails 6R load
-at most 5Mhz Ft
Seems like BD249C are not robust enough? If the BD249C are OK, I ll be very happy.
-"european" type
-T0220 or similar
-32VDC rails 6R load
-at most 5Mhz Ft
Seems like BD249C are not robust enough? If the BD249C are OK, I ll be very happy.
They are perfectly OK; the BD245C would also be suitable. There are more modern, TO220 series like the BDT93 that would also be usable (this exact type is a bit short for this power though)
Either breakage (reduced longevity) or awkward tonality trouble due to current versus linearity, because those are too small. Instead, I think that you want MJL21194, which can probably handle your 85W while maintaining good linearity.
I think you are right, most probably i will remove some turns from the power transformer to make it 25-26 Volts AC, or use the MJL's
The SOA of BD249's is quite good: the locus 32V,5.33A is almost within the DC SOA, which means it would be capable to drive a purely reactive |6Ω| load down to very low frequencies without risk.
In practice, it is a more than mature process (they were introduced in the early seventies), and unless you happen to stumble on fakes, even +/-32V-4Ω is safe, unless you use your amp all the time at/near clipping level on difficult speakers
Probably you meant "DC" because you stated that you have "32V DC" in your first post unless not having any confusion. 32V DC means 22V AC. 26V AC means 35V DC.
still need more information
Hey guys...looking for some more reviews of what the amplifier sounds like....seems that all depends on choice of components but I am thinking that its topology might have a signature ya? ....
anyways I would like to build one..... possibly with to3 case toshiba 2sc1030 outputs...suitable drivers?
Thank you for putting this up to DIY!
Lawrence
Hey guys...looking for some more reviews of what the amplifier sounds like....seems that all depends on choice of components but I am thinking that its topology might have a signature ya? ....
anyways I would like to build one..... possibly with to3 case toshiba 2sc1030 outputs...suitable drivers?
Thank you for putting this up to DIY!
Lawrence
It sounds like an amplifier. That is, it doesn't have a sound - it amplifies. Sound signatures are exclusive to speakers, distortion pedals, etc.
ya maybe I should have worded it somewhat differently but IMO all components ampifiers speakers etc etc... have a sonic signature....if what you say above were true why DIY then we would all have perfect amplifiers etc..
My apologies. I had looked at the wrong datasheet. On the right datasheet, it looks like BD249C are fine for use with your 32+32VDC rails and your 6 ohm speakers.
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You can find opinions of builders interspersed here and there in the main thread, but you will need a good deal of motivation to locate them all...
Outside of DIYaudio, there are also reviews, but generally not in English
The type of driver is not very influenced by the build: in your case, you appear to target a lower power Circlophone, but all the types already proposed are suitable: they are a bit overdimensioned but it doesn't hurt.
You can also include lower power types in TO5, like 2N2905 or similar
if you or anyone happends to have links to these review even in another language I can always translate this would be more helpful ..
I am also going to do what no one has done before replace the amp section in one of my beloved receivers which has very good +-29 volt supplies
Lawrence
A little fast bit. Okay, take note of C11 on Elvee's original schematic:
In most cases that voltage can be achieved with an 18+18vac transformer (15+15vac transformer also usable) and a simple power supply board.
As for drivers, he used ST's BD140.
It does not do the typical group delay, boomy bass nor upper midrange compression AT ALL. A circlophone will Not do shout covered up by warm blur. This benefit comes at the cost of hearing a slight amount more of all else, but it is possible that is good news. It does do a High End lifelike sounding dynamic presentation with the spaces between the notes elegantly illustrated. It has many highly desirable aspects.Sk8Ter said:
The Circlophone is slightly overcomp yielding not high end imaging at the cost of shout but rather high end dynamics and lower listening fatigue. That is adjustable somewhat.
The one thing the Circlophone does better than all other amplifiers on the planet is cost effective bass.
I cannot say it is perfect, but I can say that you're going to enjoy this.
You won't get bored listening with a Circlophone.
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Thank you all for your time, I will proceed and keep you posted on the results
It is going to be compared with a single-ended tube amp of 6Watts. If it doesnt sound different from THAT, i dont know what will lol.
It is going to be compared with a single-ended tube amp of 6Watts. If it doesnt sound different from THAT, i dont know what will lol.
Thanks for the encouragement
Sounds Exciting ...my reference amplifier is in the small power output class of 25wpc....see nothing has come too close to do what it does ....IMO a true tuff act to follow but we shall see........ when i get it done you will hear from me what I really think!.....what i have always tried to achieve is ...the elusive musical event in my home to the scale of the room...no studio crap here ....
Thanks guys ..oh i also did a google search not much information but from here...so if you have the links please post them ya?
Lawrence
A little fast bit. Okay, take note of C11 on Elvee's original schematic:
In most cases that voltage can be achieved with an 18+18vac transformer (15+15vac transformer also usable) and a simple power supply board.
As for drivers, he used ST's BD140.
It does not do the typical group delay, boomy bass nor upper midrange compression AT ALL. A circlophone will Not do shout covered up by warm blur. This benefit comes at the cost of hearing a slight amount more of all else, but it is possible that is good news. It does do a High End lifelike sounding dynamic presentation with the spaces between the notes elegantly illustrated. It has many highly desirable aspects.
The Circlophone is slightly overcomp yielding not high end imaging at the cost of shout but rather high end dynamics and lower listening fatigue. That is adjustable somewhat.
The one thing the Circlophone does better than all other amplifiers on the planet is cost effective bass.
I cannot say it is perfect, but I can say that you're going to enjoy this.
You won't get bored listening with a Circlophone.
Sounds Exciting ...my reference amplifier is in the small power output class of 25wpc....see nothing has come too close to do what it does ....IMO a true tuff act to follow but we shall see........ when i get it done you will hear from me what I really think!.....what i have always tried to achieve is ...the elusive musical event in my home to the scale of the room...no studio crap here ....
Thanks guys ..oh i also did a google search not much information but from here...so if you have the links please post them ya?
Lawrence
In the meantime, I decided to go with 2SD5200 due to hfe versus current linearity that BD249's can't even approach. Will keep you posted.
If you meant 2SC5200, need to notice that such high FT devices haven't well tested and haven't successfully built so far.
Yes, that was a typo.
Seems like I ll be on the bleeding edge, but on the other hand these transistors seem to be the "preferred series" that a lot of current designs use, so I think it will be of interesting for other builders.
Now, I m waiting for delivery from Singapore.