Years ago, I designed a phase splitter that was so good that I could not tell any difference when it was in or out of the system. Great, natural sonics, little artificial flavorings. Difficult to design, some. Made it to my monoblocks.
A phase splitter does not pull the signal apart and then put it together again, but I think I understand what is meant. Almost all phase splitters will have different output impedances (Z) per left and right output, although some designs only slightly. 180 degree out of phase is also important over a wide range of frequencies, and that can be achieved as well. This is best achieved by using high Gm and low plate resistance tubes. Of course SS is more complex by definition.
Simply put, the input signal is applied in such a way that the two output signals are 180 degrees out of phase over a very wide frequency range. Voltage is the main consideration, but some current is also needed to charge and discharge the output capacitance, interconnect capacitance, and amplifier input capacitance. The capacitances will depend upon the IC capacitance and device/gain of the amp input device.
Cheers
Steve
Thanks for explanation Steve. Synergy of components is a well known fact. But actually what is behind synergy ? Is it electrical characteristics of each component that meld together ? Is is something else related to sonic character of components ?
I find it a tired argument or phrase used to explain why certain components go well with each other. T
here must be an engineering reason I would like ALL to know. Maybe I should start a new topic.
charles
All synergy is, is an attempt to combine separate elements to obtain maximum sonic quality. Synergy is variable as it depends upon how the combination sonic quality compares to perfect entities that are combined. (Let's leave out the room and speakers for now.)
The main culprits are lack of correct designing, and lack of understanding how sensitive the "ear" is.
Virtually every part is critical to the sonic properties of a component. That includes parts in the power supply (and number of stages), parts quality in the rest of the circuit, harmonic distortion properties, frequency response etc.
The "ear" is incredibly sensitive to tonal abnormalities etc based upon Olson, Rane, Fletcher, Jensen, RCA Radiotron Designers Handbook etc, and I have confirmed before and after reading these sources over the years.
If we are dealing with a preamplifier to amplifier combination, we look for enough signal voltage to drive the amplifier. This is usually not any problem. What could be a problem though, is output signal current capability of the preamplifier. Is that signal current enough to drive the output capacitance, IC capacitance, and amplifier input capacitance?
With not enough signal current, as the frequency rises, the HD distortion rises. I have seen sine waves become triangular waves as the frequency rises. But one does not need a buffer stage. A 12au7/6sn7/6dj8 type tubes generally provide plenty without any buffer. If a buffer is needed, there is one more stage to degrade the music.
As a very simple example of synergy; if a preamplifier is full sounding, we tend to find an amplifier that is thin sounding to compensate. Unfortunately, there is usually more than one flaw in a component, unless we are dealing with superb pieces of equipment.
And some flaws one cannot cancel out. For instance, how does one cancel smearing caused by a component? If a component is so full it loses detail, how can that inner detail be recreated? Some of the biggest problems I see in components are;
1. Insufficient power supply filtering stages
2. Insufficient size and quality of coupling capacitors in tube components
My philosophy is to perform listening tests over months for each part, if possible, and each component for accuracy in absolute terms. With proper design, there will be less signal degradation, thus higher synergy can be achieved. Then I would design the speaker.
A couple of reasons why speaker sound so different are:
1. Different frequency responses and price range.
2. Different venue testing the speaker
3. Different quality components in the speaker.
4. Different quality active components in the test system. If a designer is using components that lack sufficient high frequency response, then the speaker will probably be bright sounding.
Etc.
Based upon these reasons, I would provide variable adjustments so the customer can create the best synergy possible. I have three adjustments on my speakers alone.
Cheers
Steve