noulou
Well-known member
From the latest issue of sound on sound.
it apparently
it apparently
Portico 5042 guts
- Thread starter noulou
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edanderson
Well-known member
i've seen one of these in person. from what i saw, yeah, the little cans near the output transformers are probably some kind of tape head simulator. i never saw the bottom of the pcb, so i don't know if there are any pins coming out the bottom of those cans. the smaller cans towards the front are definitely xicon audio transformers -- they still had the xicon/mouser stickers on in the unit i saw. probably being used in one of the "zero field" configs.
quite a few ics in there.
ed
quite a few ics in there.
ed
Milkmansound
Well-known member
I have one of these - its *awesome*
it produces a very exciting distortion too
it produces a very exciting distortion too
Mailliw
Well-known member
More than the sum of its cheap parts?
clintrubber
Well-known member
[quote author="noulou"]
it apparently
Let me be the one that asks the obvious question: what's the difference between 'inductively coupled coils' and a 'transformer as we know it' ?
Regards,
Peter
it apparently
[/quote]
Let me be the one that asks the obvious question: what's the difference between 'inductively coupled coils' and a 'transformer as we know it' ?
Regards,
Peter
SSLtech
Well-known member
[quote author="Mailliw"]More than the sum of its cheap parts?[/quote]
Well, not all the parts are cheap. Those output transformers are Da Bizzniss, for example. The PCBs are well made.
...and -crucially- they sound better than ANYTHING you can name made by API/Universal Audio/Neve corporation/SSL or just about ANY other company that you can name.
I'm deadly serioius.
Stop looking inside and thinking "how can that be any good?", and LISTEN to one.
amorris did that recently with some mic pre/EQs, and he bought one. My bosses did that recently, and they bought twelve. Most people who have heard them have bought them.
They sound bigger than you can imagine.
-And check my posting history, I'm pretty conservative. I don't go in for capacitor snobbery, cable voodoo or boutique frippery. But that doesn't alter my experience that the Portico stuff is un-be-friggin-lievably good sounding.
I mean it.
And there's a LOT of weight in those words.
Keith
Well, not all the parts are cheap. Those output transformers are Da Bizzniss, for example. The PCBs are well made.
...and -crucially- they sound better than ANYTHING you can name made by API/Universal Audio/Neve corporation/SSL or just about ANY other company that you can name.
I'm deadly serioius.
Stop looking inside and thinking "how can that be any good?", and LISTEN to one.
amorris did that recently with some mic pre/EQs, and he bought one. My bosses did that recently, and they bought twelve. Most people who have heard them have bought them.
They sound bigger than you can imagine.
-And check my posting history, I'm pretty conservative. I don't go in for capacitor snobbery, cable voodoo or boutique frippery. But that doesn't alter my experience that the Portico stuff is un-be-friggin-lievably good sounding.
I mean it.
And there's a LOT of weight in those words.
Keith
Rob Flinn
Well-known member
[quote author="Mailliw"]More than the sum of its cheap parts?[/quote]
I'm with Keith.
These sort of comments are just laughable. You are trying to equate the parts cost to to the retail price. You are simply not taking in to account paying for development, premises, manufacturing, insurance, wages, advertising amongst many other hidden costs.
Someone said to me just the other day that if you take the parts cost then normally you need to sell it for 7 times that amount to make some profit & pay all these extra bills. I'm no accountant, but I could see this to be the case quite easily, based on my own experiences.
I'm with Keith.
These sort of comments are just laughable. You are trying to equate the parts cost to to the retail price. You are simply not taking in to account paying for development, premises, manufacturing, insurance, wages, advertising amongst many other hidden costs.
Someone said to me just the other day that if you take the parts cost then normally you need to sell it for 7 times that amount to make some profit & pay all these extra bills. I'm no accountant, but I could see this to be the case quite easily, based on my own experiences.
Mailliw
Well-known member
[quote author="Rob Flinn"][quote author="Mailliw"]More than the sum of its cheap parts?[/quote]
I'm with Keith.
These sort of comments are just laughable. You are trying to equate the parts cost to to the retail price. You are simply not taking in to account paying for development, premises, manufacturing, insurance, wages, advertising amongst many other hidden costs.
Someone said to me just the other day that if you take the parts cost then normally you need to sell it for 7 times that amount to make some profit & pay all these extra bills. I'm no accountant, but I could see this to be the case quite easily, based on my own experiences.[/quote]
I was referring to the sound, not the retail cost. :razz: Keith's post does answer my question, however.
I am not being critical in that sense either, just curious.
I'm with Keith.
These sort of comments are just laughable. You are trying to equate the parts cost to to the retail price. You are simply not taking in to account paying for development, premises, manufacturing, insurance, wages, advertising amongst many other hidden costs.
Someone said to me just the other day that if you take the parts cost then normally you need to sell it for 7 times that amount to make some profit & pay all these extra bills. I'm no accountant, but I could see this to be the case quite easily, based on my own experiences.[/quote]
I was referring to the sound, not the retail cost. :razz: Keith's post does answer my question, however.
I am not being critical in that sense either, just curious.
TomWaterman
Well-known member
[quote author="SSLtech"][Those output transformers are Da Bizzniss, for example.[/quote]
I understand Rupert is getting his transformers from China, SE Electronics the mic manufacturer in fact. For something like $8 a pop...
Not bad. I believe Keef but I have one question. Inside every Portico I have seen has stacks of ICs in them and not much in the way of discrete transistors yet they are sold as being discrete single sided...what gives?
I see a pair of TO transistors near the OP txs presumably for line driver?
-T
I understand Rupert is getting his transformers from China, SE Electronics the mic manufacturer in fact. For something like $8 a pop...
Not bad. I believe Keef but I have one question. Inside every Portico I have seen has stacks of ICs in them and not much in the way of discrete transistors yet they are sold as being discrete single sided...what gives?
I see a pair of TO transistors near the OP txs presumably for line driver?
-T
SSLtech
Well-known member
They are single-sided up to 2V p-p, unless Rupert has changed his design philosophy. -Same as the 9098i, 5534s can be made to sound FABULOUS, and operate in single-sided mode for ALL small signals, reverting to class AB for larger peaks only. I must confess, I don't recall them saying it was discrete anywhere... If they do say "single sided" and they're using the 9098i trick, I bet it's a marketing decision, and one that I'm VERY uncomfortable with, so we probably agree on that, but discrete it very plainly isn't. -Perhaps the marketing guys insist on saying single-sided and leave everyone's minds to fill in the 'discrete' part?
Quad did a very similar same thing with their current-dumping topology. Class A where it matters (delicate, small microdynamics) and Class AB where there's a distinct advantage (blood-and-thunder headroom).
Yeah, the real reason that I 'jumped' so hard on that 'sum of cheap parts' bit was not to get on the poster's case, as to try and balance the issue.
Posters who read this are not all balanced, reasonable people, and -picking a gearslutz-mentality example- may find this thread having searched "portico circuitry" for example. -If they scan it and read stuff like "cheap parts", that's how "It's just an expensive name on an ordinary product" takes root.
Incidentally, I heard of an interesting test recently: The sales manager for Rupert Neve Designs set up two sets of output paths in Pro-Tools, one with 16 channels summed through a 'typical' console, and a second one with the smae sixteen channels summed through the porticos. Both paths were aligned using 1kHz level reference tones...
...and then the Portico paths were all REDUCED by 1dB.
The client was asked to say which sounded louder, with the meters hidden. He chose the Porticos. When they ran tone through them and showed him the meter readings, he bought sixteen.
Keith
Quad did a very similar same thing with their current-dumping topology. Class A where it matters (delicate, small microdynamics) and Class AB where there's a distinct advantage (blood-and-thunder headroom).
Yeah, the real reason that I 'jumped' so hard on that 'sum of cheap parts' bit was not to get on the poster's case, as to try and balance the issue.
Posters who read this are not all balanced, reasonable people, and -picking a gearslutz-mentality example- may find this thread having searched "portico circuitry" for example. -If they scan it and read stuff like "cheap parts", that's how "It's just an expensive name on an ordinary product" takes root.
Incidentally, I heard of an interesting test recently: The sales manager for Rupert Neve Designs set up two sets of output paths in Pro-Tools, one with 16 channels summed through a 'typical' console, and a second one with the smae sixteen channels summed through the porticos. Both paths were aligned using 1kHz level reference tones...
...and then the Portico paths were all REDUCED by 1dB.
The client was asked to say which sounded louder, with the meters hidden. He chose the Porticos. When they ran tone through them and showed him the meter readings, he bought sixteen.
Keith
TomWaterman
Well-known member
Fair enough I might be filling in the 'discrete' part sub-consciously!
I got some drawings from RND for their new 5088 console and its looking great. Nice feature set indeed.
Pretty interesting test that Keef. Picking the quieter one even after all that, they surely must have sounded great to do that...what with the bias normally provided by a louder source. Damn.
The trick is Class-A biasing the 5534 with a pull-up resistor on the output ye?
-T
I got some drawings from RND for their new 5088 console and its looking great. Nice feature set indeed.
Pretty interesting test that Keef. Picking the quieter one even after all that, they surely must have sounded great to do that...what with the bias normally provided by a louder source. Damn.
The trick is Class-A biasing the 5534 with a pull-up resistor on the output ye?
-T
burdij
Well-known member
Mr. Neve mentions that they have a new discrete opamp design in his lecture. Doesn't give any details though.
Tekay
Well-known member
He used the pull up thing in the Focusrite EQ as well. 10k from the IC output to the positive rail, output always followed by a 100uF / 16v cap and a 4k7 to ground after the resistor.
SSLtech
Well-known member
No, it's biased 1V above (or below) ground, then taken to GROUND with a resistor. Hence the same side conducts all the way up to 2V peak-to-peak, typical signals.
This completely avoids the crossover issues which happen with most op-amp designs when the signal gets most vulnerable (when it's very quiet).
Keith
This completely avoids the crossover issues which happen with most op-amp designs when the signal gets most vulnerable (when it's very quiet).
Keith
A bit off topic but this threads posts about how it sounds louder might have more to do with the output transformer, core size, alloy, winding, BH etc....
I believe I hear more changes in "tone" with tube or solid state and transformer condenser microphone circuits from the transformer.
Offsetting from center just puts the crossover and open loop output resistance at a different spot of the output swing. Could the offset be to have a known DC polarity across the polar Al electrolyics?
I believe I hear more changes in "tone" with tube or solid state and transformer condenser microphone circuits from the transformer.
Offsetting from center just puts the crossover and open loop output resistance at a different spot of the output swing. Could the offset be to have a known DC polarity across the polar Al electrolyics?
clintrubber
Well-known member
Hmm, those two 'mods', would be interesting to compare these by ear and by measuring, say with a 5532/5534 (assuming these are used in the Portico).
So three cases then:
#1 nothing, #2 10k pull up, #3 biasing the opamp away from the middle.
I don't recall what Douglas Self already says about such additions; his measurements show that the 5532 is already pretty blameless as is.
http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm
http://www.dself.dsl.pipex.com/ampins/webbop/5532.htm
The 'by ear' will reveal different stuff then, I'm honestly curious.
Regards,
Peter
BTW, I realize that #3 above is also already accomplished by adding a NPN & PNP stage to an opamp and entering the biasing-diodes not in the middle but at the top (so not 1 V shift but 1 Vbe; but comparable effect).
So three cases then:
#1 nothing, #2 10k pull up, #3 biasing the opamp away from the middle.
I don't recall what Douglas Self already says about such additions; his measurements show that the 5532 is already pretty blameless as is.
http://www.dself.dsl.pipex.com/ampins/webbop/opamp.htm
http://www.dself.dsl.pipex.com/ampins/webbop/5532.htm
The 'by ear' will reveal different stuff then, I'm honestly curious.
Regards,
Peter
BTW, I realize that #3 above is also already accomplished by adding a NPN & PNP stage to an opamp and entering the biasing-diodes not in the middle but at the top (so not 1 V shift but 1 Vbe; but comparable effect).
Tekay
Well-known member
ISA 430 Schematics shows a 10k from output to A+ ?
clintrubber
Well-known member
[quote author="Gus"]Offsetting from center just puts the crossover and open loop output resistance at a different spot of the output swing. Could the offset be to have a known DC polarity across the polar Al electrolyics?[/quote]
Both those methods mentioned force a DC-current (be it source or sink) from the output of the opamp.
The offsetting from center alone doesn't do that but as said there's an additional resistor that forms a load for the created DC-offset.
(So while dimensioning may be different,) in that respect it's the same idea as the 'pull to rail'-resistor, just to a different rail (in this case the 'middle rail').
The cap-polarizing as you mentioned for the DC-offset method is indeed a nice bonus.
Would be interesting to get more facts/details/values on the table about both observed methods.
Hmm, assuming a few cascaded opamp-stages, the away-from the middle biasing for the next opamp could result in a zero net-voltage across the coupling cap. That could be solved by adding another cap in series, but then we have the known scheme of two anti-series caps with a pull-to-rail high-valued resistor to bias the mid-point...
Regards,
Peter
Both those methods mentioned force a DC-current (be it source or sink) from the output of the opamp.
The offsetting from center alone doesn't do that but as said there's an additional resistor that forms a load for the created DC-offset.
(So while dimensioning may be different,) in that respect it's the same idea as the 'pull to rail'-resistor, just to a different rail (in this case the 'middle rail').
The cap-polarizing as you mentioned for the DC-offset method is indeed a nice bonus.
Would be interesting to get more facts/details/values on the table about both observed methods.
Hmm, assuming a few cascaded opamp-stages, the away-from the middle biasing for the next opamp could result in a zero net-voltage across the coupling cap. That could be solved by adding another cap in series, but then we have the known scheme of two anti-series caps with a pull-to-rail high-valued resistor to bias the mid-point...
Regards,
Peter
clintrubber
Well-known member
Let's keep this moving.
