Contrary to popular belief, the Martin Logan electrostatics have powered woofers that let you hear more bass if the amplifier has better low end punch. Please refer to the stereophile review of the montis where they can validate what I am stating here. The bass improves and sounds as if you went to the back of the speaker and turned the dial up a few notches. Regarding the fact that the Martin-Logan Renaissance and Montis speakers incorporate powered woofers, yes, I would certainly expect that their bass performance would vary significantly depending on the amplifier that is used. Just as bass performance can be significantly affected by a preamp or a source component, even though those components provide no power to the speakers. However, since those speakers draw nearly negligible amounts of current and power from the amp at deep bass frequencies, and also given that the amp being used will not be exposed to any back-emf from the woofer, I would be cautious in extrapolating from these results expectations about what kind of bass performance can be expected with non-powered speakers. Also, as George mentioned the impedance of these and many other electrostatics descends to very low values in the upper treble region, about 0.5 ohms at 20 kHz in the case of these particular speakers. With that impedance being highly capacitive (and therefore more demanding of the amp) in much of the treble region. While most non-electrostatic speakers have impedances that either rise or remain relatively constant in the treble region, and that usually become increasingly inductive, rather than capacitive, at high frequencies. So while I extend my congratulations to the OP for a job well done, and for providing us with a great deal of valuable information, I would be cautious in extrapolating from results with these two speakers expectations as to how an amp would perform if it were to be used with non-powered and/or non-electrostatic speakers. Regards, -- Al |
WC, while the Cardas site doesn’t provide specs for the inductance and capacitance of the Clear Beyond speaker cables, I found here that inductance is 0.01 uH/foot, which is extraordinarily low, and capacitance is 446 pF/foot, which is fairly high. Also, Stereophile’s measurements of the DAW indicate that the phase angle of its impedance reaches its most extreme value (in the direction of being capacitive) at 57 Hz, very close to 60 Hz. Just a guess, but I would speculate that the high capacitance of the cable plus the very capacitive nature of the DAW near 60 Hz, coupled with the lack of significant inductance in the cable that might mitigate the effects of the speaker’s capacitance on the amp, are making the Gryphon unhappy. BTW, in saying this I’m inferring from your posts that the hum occurs not only when nothing is connected to the Gryphon’s inputs, but also when a powered up preamp is connected. Leaving an amp’s inputs unconnected is not always a meaningful test. Best regards, -- Al |
WCSS 4-17-2020
Gryphon recommends to - Steer away from speaker cables for Gryphon amplifier with a coaxial design, active shielding or special boxes that will add-on different types of filtration. A speaker cable with a coaxial design or with active shielding will in most cases have a much lower bandwidth than the amplifier and therefore the amplifier will be met with too high a capacitance load causing oscillation of the amplifier. There is no need to actively add filtration on an analogue amplifier. It doesn’t serve the final reproduction of the music any good.
- Use speaker cables with a low capacitance and a wide bandwidth in order to match the specs of the amplifier’s bandwidth and output impedance. From Gryphon’s standpoint, there is no need to add more “negative” filtration to the system given their emphasis to have the finest level of tonal balance and neutrality.
As I indicated in my post dated 4-12-2020 the Cardas Clear Beyond cables are the antithesis of low capacitance, at 446 pf/foot, although they are not as high in that respect as the Goertz cables Jetter mentioned. And Dpac has provided a good explanation of why the problem only occurs in the left channel. Also, as I mentioned in the earlier post the DAW’s impedance is significantly capacitive in the vicinity of 60 Hz, which is probably contributing to the issue and putting the amp’s left channel over the edge. I agree with Jetter and Dpac that a Zobel network, or perhaps even just a 10 ohm resistor capable of handling the necessary high power levels, would likely solve the problem. But basically everything seems to point to the Clear Beyond being the wrong cable for this application. I’ll add that a primary design goal of the Clear Beyond was presumably to provide ultra-low inductance (0.01 uH/foot, in the same general ballpark as Goertz), with the high capacitance being a side-effect of the particular design techniques Cardas used to accomplish that. But IMO such low inductance is overkill by a wide margin. Especially with speakers such as the DAW (and many other dynamic speakers, as opposed to electrostatics) which have an impedance which rises at high frequencies. (The impedance presented by an inductance is proportional to frequency, and will matter less if the speaker’s impedance also rises as frequency rises). Regards, -- Al |
Most of my listening is to classical music. Average levels tend to be in the mid-70s. Brief dynamic peaks on many orchestral recordings tend to be in the low to mid 90s. Brief dynamic peaks on a few recordings having exceptionally wide dynamic range (e.g., Stravinsky's "Firebird Suite" on Telarc; Prokofiev's "Romeo and Juliet" on Sheffield Lab) reach close to 105 db.
Measured with a Radio Shack digital SPL meter set for C-weighting and fast response, at my 12 foot listening distance.
Regards,
-- Al
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Some thoughtful and excellent posts by Viber6, IMO.
In fairness to Techno_dude, though, while I certainly wouldn't go as far as to say that ARC "tries to make their tube gear sound like SS," I believe that a major contributor to his perception is the fact that ARC amps tend to use more feedback and consequently have lower output impedances and higher damping factors than many and perhaps most other high quality tube amplifiers.
The interaction of that relatively low output impedance (for a tube amp) with a speaker's variations of impedance as a function of frequency will tend to have tonal consequences that come relatively close to those that would result with a solid state amp, nearly all of which have output impedances that are near zero and inconsequentially small relative to speaker impedances.
Stated another way, ARC tube amps tend to act more like voltage sources than most other high quality tube amps. Meaning that for a given input voltage to the amp it will come closer to maintaining a constant voltage into varying load impedances than most other high quality tube amps (and therefore delivering more power into low impedances than into high impedances), as long as it is operated within its maximum voltage, current, power, and thermal capabilities.
Regards,
-- Al
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A point to be aware of regarding the possibility of pairing a Spectral power amp with the Ref10 (or any other) ARC line stage or preamp: All currently produced Spectral power amps, and some of their older models, have input impedances of 10K. (A few of their older models have input impedances of 100K). All or nearly all ARC line stages and preamps have a load impedance specification of 20K **minimum.**
Regards,
-- Al
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4425 9-18-2018
All ARC preamps are really not designed to drive subwoofers except possibly REL.
The line-level input impedance of many and I believe most REL subs is 10K, well below ARC’s usual load recommendation of 20K minimum for their line stages and preamps. The input impedance of the power amp, that would be paralleled with the input impedance of the sub for one of the two signals in the preamp’s balanced pair of output signals if the power amp is connected via XLR and the sub via RCA, would further reduce the 10K load impedance. The speaker-level connections provided by REL subs would work well with ARC power amps, but there is an important caveat. ARC fully balanced tube power amps typically have their circuit ground connected to the 4 ohm tap, not to the common tap. So in the case of a fully balanced ARC stereo tube amp the black ground wire of a REL sub’s speaker-level input should be connected to the 4 ohm tap. The red and yellow signal wires should be connected to the 8 ohm tap of the corresponding channel, or alternatively to the 16 ohm tap if 16 ohm taps are provided. In the case of monoblocks I would consult with ARC as to what to do with the black wire. On another note, Bill_k makes a good point about the reference in the Merrill literature to GHz speeds. As far as I can see none of the information provided at their website makes clear what parameter is in the GHz range (and for that matter I wasn’t able to even find a clear statement that it applies to the switching frequency), and a specification of signal bandwidth is not provided. Regards, -- Al |
Thanks, Bill. The one reference to GHz speeds I see at that link is a statement that "the Gallium Nitride Transistors can operate in the Gigahertz range." I'm sure that is true, but of course that statement provides no indication of how fast the transistors are switched in the amp.
Best regards,
-- Al
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Viber6, yes, it appears to me that GaN transistors are used in the output stages of the new Merrill amps. And consequently they are directly in the signal path, and have nothing to do with the power supply. However, it also appears that the amps are operating in class D, or some variant thereof. (In addition to the power-to-weight ratio of the amp being strongly suggestive of that, the designer specifically states so at the link Bill provided). Which means that the transistors in the output stage of the amp are being switched, at high speed. I’m pretty sure that Bill sees it the same way.
And although the transistors themselves are capable of being switched at GHz frequencies, that says nothing about what speed they are actually being switched at. All I would infer from the writeups is that the signal bandwidth is likely to be higher than the bandwidth of all or nearly all other audio amplifiers, probably including the Spectrals.
Regards,
-- Al
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As usual Bill_k is of course entirely correct in his comments about class A.
I would add that the reduction in amplifier temperature that occurs when a class A amp is delivering a lot of power to the speakers is unlikely to be noticeable, for two reasons.
First, a class A amp has low efficiency, meaning the ratio of max power out to AC power in. For example the Pass Xs150 monoblocks are rated to provide an output of 150 watts max while drawing an AC input of 700 watts. In that example the amp will never be dissipating (converting into heat) less than 700 - 150 = 550 watts, and will be dissipating significantly more than that most of the time.
Second, since speakers convert just a very small fraction of the power that is supplied to them into sound, with the rest of that power being converted into heat, if that amp is supplying 150 watts to a speaker, and therefore dissipating only 550 watts by itself, most of the 150 watts the amp is not dissipating will be converted into heat anyway, by the speaker.
In the case of a class A amp, therefore, it is easy to quantify how much power is converted into heat and injected into the room. To a very close approximation it is equal to the amp’s specified power consumption. For a pair of Xs150s that would be 1400 watts; for a pair of Xs300s that would be 1800 watts.
Also, btw, how hot an amp may feel if it is touched on its heatsinks or elsewhere has no direct relevance to that, and an amp that may seem cooler to the touch might actually be putting more heat into the room than one that seems to run hotter, depending on the design of the heat sinks and other aspects of the design of the amps. What matters is how much power the amp consumes. To illustrate that point, consider the difference in surface temperature between a 100 watt light bulb and an amp consuming 100 watts.
To answer Viber’s question, the output transistors or tubes in a class A design conduct a bias current (which is the current the output devices conduct when no signal is present) that is greater than the maximum amount of output current the amp is designed to be able to deliver. When a signal is present some of that current is diverted to the speaker. In a class AB design the output transistors or tubes just conduct a small bias current, and the presence of a signal causes them to conduct larger amounts of current, most of which is sent to the speaker.
Regards,
-- Al
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Thank you for the nice words about my post, gentlemen. With respect to the last paragraph of my post I should clarify that in the case of class A tube amps having output transformers the output tubes themselves will of course not conduct more current than the amp is capable of supplying to the speaker. The output transformer will step up the current supplied by the output tubes substantially, while stepping down the voltage supplied by the tubes correspondingly, such that the amount of power sent out of the transformer (approximately equal to voltage x current) will be approximately the same as the amount of power sent into it by the tubes (neglecting minor power losses that occur in the transformer itself).
Best regards
-- Al
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I agree with Viber’s comments about damping factor.
Usually damping factor is defined on the basis of an 8 ohm load. Assuming that is the case here, and assuming the spec is accurate, a damping factor of 5000 means that the amp has an output impedance of 8/5000 = 0.0016 ohms. While the combined resistance of the two conductors of say a 10 foot 10 gauge speaker cable is 0.02 ohms, 12.5 times as much as the output impedance of the amp.
So with that speaker cable the damping impedance presented to a speaker by an amp having a damping factor of 5000 will be 0.02 + 0.0016 = 0.0216 ohms. Not much different than the damping factor limitation imposed by the cable itself, and still vastly smaller than the impedance of the speaker (that ratio is what matters), especially in the bass region.
So IMO it is fair to say that a damping factor in the thousands is overkill by a wide margin, and if such an amp has better bass control than an amp having a much lower damping factor the reason is something else.
Also, btw, noted designers Roger Modjeski (Music Reference) and Ralph Karsten (Atma-Sphere), while admittedly being designers of tube amps having damping factors that are far lower than the damping factors of nearly all solid state amps, have both stated in threads here that no speaker in existence needs a damping factor greater than the low double digits.
Best regards,
-- Al
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If connecting the Lampi directly into the Block Audio amps proves to be superior to having the Ref10 in the path, as the comments by WC’s wife would seem to suggest, it wouldn’t surprise me if a major contributor to that is the fact that the Block’s input impedance (10K unbalanced/20K balanced) is exactly at ARC’s 20K **minimum** load recommendation for the Ref10 (which btw is also their recommendation for most of their other preamps and line stages). And that assumes WC was using balanced connections between the Ref10 and the Blocks; the Block’s 10K unbalanced input impedance would be even worse.
An output impedance spec or measurement, or alternatively a minimum load recommendation, doesn’t seem to be available for the Lampi Pacific, but given that it uses a power tube in its output stage, as well as a high quality coupling capacitor, I would think it likely that it could handle the 10K load it would see with its unbalanced-only outputs without difficulty.
Regards,
-- Al
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WC, I may have missed your mentioning it, but are the Wireworld cables you use to connect the Ref10 to the Blocks balanced or unbalanced?
If they are balanced, perhaps one factor (probably among several) contributing to what the Ref10 brings to the table when inserted between the Lampi and the Blocks is simply that the Blocks may sound better when provided with balanced inputs than when provided with unbalanced inputs. I note that the manual for the Blocks specifically recommends the balanced inputs "for best sound performance." Which of course cannot be done with the Lampi connected directly to the amps.
And if they are unbalanced, trying balanced cables between the Ref10 and the Blocks at some point would certainly seem to be in order. Not only because it may be more optimal for the Blocks, but also because it may be beneficial with respect to what I mentioned earlier about the marginal impedance compatibility between the Ref10 and the Blocks.
Regards,
-- Al
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To add to the foregoing comments about the benefits a preamp can provide, without a separate preamp some DACs will not be able to drive some power amps to full power.
The Lampi Pacific is a case in point, when paired with some of the power amps that have been mentioned. It has a specified maximum output voltage of "6 V pp" (i.e., 6 volts peak-to-peak), which is 2.12 volts based on the usual "RMS" (root mean square) way of defining such things. The Pass XS300 that has been discussed, like most Pass amps, has a specified gain of 26 db. While the XS300 is capable of 300 watts into 8 ohms and 600 watts into 4 ohms, a gain of 26 db applied to an input of 2.12 volts means that the Pacific DAC would not be able to drive the XS300 to more than 225 watts and 450 watts, respectively, into those impedances. And that would be with the volume control at max, and with a recording whose peaks reach very close to "full scale," i.e., to the maximum possible digital value. Some recordings are engineered such that they fall several db short of doing that, which would mean that more than half of the XS300’s power capability could not be utilized with those recordings, even with the volume control at max, if it were directly driven by the Pacific.
Regards,
-- Al
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A symphony I recommend to those who have not had much exposure to classical music is Prokofiev's short (~ 15 minute) "Classical Symphony," a work that IMO is just about impossible to dislike. Here is an excellent video of an excellent performance: https://www.youtube.com/watch?v=p5jL6Ma9tvkRegards, -- Al
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Jafox 2-16-2019
Other than playing with the shield, if there is one, tying it to the ’-’ line at one end of the cable or the other, or perhaps a "network" on one end or the other, designating a speaker cable as "directional" sounds more like hype than anything. Perhaps a resident technical guru here like almarg could inject some value here. Thanks for the mention, John. I agree with your statement 100%. I say that despite a variety of "explanations" of wire directionality that have been proffered by some manufacturers and certain frequent participants in cable-related threads here and elsewhere, relating variously to crystal structure, how the wires are drawn in the manufacturing process, the direction in which noise may "prefer" to propagate in the wires, the breakin effect asserted in the statement by Nordost that was quoted above, etc. As I see it, when it is not practical or possible to obtain a quantitative perspective on explanations that may be offered for a claimed effect, that would provide some indication of whether or not the effect may be great enough in degree to have a reasonable chance of being audibly significant, there is virtually no limit to the explanations that can be conjured up and asserted. And consequently such explanations amount to speculation at best, perhaps tinged with conflict of interest in the case of some manufacturers. As an aside, btw, I **can** envision that a symmetrically designed cable conducting digital audio signals might sometimes exhibit directional properties. Digital audio signals have significant frequency content at tens of MHz, and higher in some cases, which conceivably could mean that minor mechanical differences in how the wires are soldered or otherwise attached to the connectors at each end might result in differences in the degree and timing of reflection effects that occur at those RF frequencies as a result of impedance mismatches between the the components and the "characteristic impedance" of the cable and connectors. Which in turn, depending on which way the cable is connected, might in some circumstances affect the waveform of the signal that is received by the destination component to a degree that contributes to timing jitter at the point of D/A conversion. Also, kudos for suggesting that any such findings be verified by re-trying the "wrong" direction, which would reduce the possibility that a perceived difference may have resulted from extraneous variables such as differences in the warmup state of the equipment, reseating of the connectors, etc. My perception over the years has been that it is all too common for audiophiles to attribute perceived effects to the wrong variable, as a result of inadequately thorough methodology. Especially when it comes to effects that are seemingly implausible. IMO. Best regards, --Al |
Viber6 2-17-2019
I was just asking if you could take a simple cable like zip cord with
known specs at different gauges, and approximately predict that bass
frequencies are reduced more than high freq. You can make up some
numbers for some amps or speakers you know, so you can estimate the
effect, or just use a pure resistor as a model for a speaker (Maggies
are said to be a pure resistive load). If this is still not possible
for you to predict this, I thank you and respect your insight. No, I still wouldn't want to make any such predictions. Also, given the many variables and unknowns I cited in my previous post, as well as the fact that perceived tonal balance can be affected by more than just frequency response (e.g., by low level distortions of various kinds), I would expect that any correlation between gauge and perceived frequency response/tonal balance would be a loose one at best. Best regards, -- Al
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Viber6 2-16-2019
Yes, I have found that thinner speaker cable yields a more treble oriented balance.... Maybe almarg can help with some sensible science to back up our listening impressions, rather than the pseudoscience of many cable designers. Thanks for the mention, Viber, but that involves so many variables, at least potentially, that I would not want to speculate as to why that may be true in many cases. Those variables would include not only the characteristics of the cable, such as resistance, inductance, capacitance, length, "characteristic impedance," the thickness and dielectric absorption characteristics of the insulation, skin effect (the importance of which, btw, though not necessarily insignificant, tends to be over-hyped by many manufacturers, as can be shown by calculation), but just as importantly the interactions of the cable characteristics with those of the speakers (especially their impedance characteristics over the frequency range), and with those of the amplifier (especially its output impedance, how much feedback it uses, and perhaps its bandwidth). Also, given all of those potentially significant variables and system dependencies I would be cautious in extrapolating general conclusions about such things from individual experiences, even if those experiences are particularly diverse. Not saying it can’t or shouldn’t be done, just that I would be cautious in doing so. Best regards, -- Al |
Thanks for pointing that out, RIAA. I was basing my statement on the following statement which appears near the bottom of this page of Reno HiFi’s site: Reno Hi Fi, Inc. does not sell new Pass Labs components within 100 miles of another Authorized Pass Labs Dealer (though Demo and Used Pass Labs products may be sold near another US or Canadian dealer.) New, refurbished, or used Pass Labs brand amps are available for delivery to and use in the US and Canada only. I had noticed that statement before calling Mark at Reno to place my order, and I determined that the nearest authorized dealer is 175 miles from my location. I mentioned that fact to Mark before he had a chance to bring up the subject, so I don’t know what if any applicability the statement had at that time or now. Perhaps they just haven’t updated the website to reflect present policy. Or perhaps the policy is different for First Watt products. In any event, best of luck with your SIT-3. I had considered waiting for the SIT-3 to become available when I ordered the XA25, but in my particular system its low gain (around 11.5 db if I recall correctly) would not be suitable, as the DEQX HDP-5 I use as my preamp provides essentially no gain. Regards, -- Al |
Regarding the XA25, I purchased one last year, and I have been delighted with it. It replaced a highly regarded 300B-based tube amp I had been using, a 70 watt per channel class A biased VAC Renaissance 70/70 MkIII. I found that the following review by Terry London (Audiogon member Teajay) described its sonics perfectly. (And IMO better than they were described in the Stereophile review): https://hometheaterreview.com/pass-labs-xa-25-stereo-amplifier-reviewed/I should add, though, that my speakers (Daedalus Ulysses) are very easy to drive, having a very benign almost flat nominally 6 ohm impedance curve, as well as 97.5 db/1 watt/1 meter efficiency. With those speakers, at least, it comes remarkably close to the VAC with respect to dimensionality, imaging, liquidity, and other traditional fortes of high quality tube amps, while providing a totally black background and better bass. It’s a bit less rich sounding than the VAC, but I interpret that as an increase in accuracy, which is fine as far as I am concerned. But I have no idea as to what kind of results it would provide when faced with the Neolith’s 4 ohm nominal impedance that descends to 0.43 ohms at 20 kHz, coupled with considerably less sensitivity than my Ulysses. Also, while I’m not in a position to personally comment on how its sonics compare to those of the high powered Pass class A amps, I would note that its design is substantially different in various ways, and I see no reason to assume the XA25 shares much in the way of a "house sound" with them. Also, see the comments by some other owners as well as myself in the following thread: https://forum.audiogon.com/discussions/pass-labs-xa25-amp-and-bw-804-d3 In any event, Reno Hifi (which is wonderful to deal with) offers 14 day return privileges less only two-way shipping, which is not expensive for this particular amp. And as many here are aware Pass itself provides exceptional customer support. However Reno can only sell new units (as opposed to trade-ins or demos) to those living more than 100 miles from another authorized Pass dealer. Regards, -- Al |
P.S: Upon re-reading my previous post it occurs to me that the use of the word "load" in the last sentence might create some ambiguity. Let me restate the sentence with that word deleted:
The bottom line, again, is that for a given impedance the number of db corresponding to a given voltage ratio is the same as the number of db corresponding to the resulting power ratio.
Also, to clarify further, although the prefix "deci" literally refers to a factor of 10, or one-tenth, by convention a factor of 20 is used in db calculations for voltage ratios, as shown in the formula I provided earlier.
Regards,
-- Al
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WC, regarding the moodiness of the Constellation amps, as others have suggested it could very well be AC power-related. But by any chance has the humidity in the listening room been different than usual during some of the times you’ve been using those amps? My understanding is that humidity can significantly affect the performance of electrostatic speakers, just as it has effects on static electricity. Viber6 5-17-2019
Purifi is exciting. At first, I was disappointed to read 12.8 dB gain from the module, but this is voltage gain, so the power gain is 25.6 dB (V squared divided by R=power). I doubt this is the whole circuit, which usually has an input stage before the power stage, so that manufacturers can tailor the sound by varying the input stage. The second sentence reflects a common misunderstanding. A db is a db, whether voltage or power is being referred to, and in this case the gain is 12.8 db for power as well as for voltage. The fact that for a given load impedance power is proportional to the square of voltage is accounted for in the formulas for converting voltage ratios and power ratios into db: db = 20 x log(V1/V2) = 10 x log(P1/P2) where "log" is the base 10 logarithm. So for example a gain of 6 db represents a doubling of voltage while also representing an increase of four times for power. A doubling of power would be an increase of 3 db, which is an increase of the square root of 2 (about 1.414) for voltage. But as you indicated, perhaps it is anticipated that additional gain would be provided by a separate input stage. Regards, -- Al |
@Viber6, no, I’m afraid I must disagree with your previous post, and what I stated in my previous post is correct. (Except that as explained below I misspoke when I said that "in this case the gain is 12.8 db for power as well as for voltage." As explained below, in the case of an audio amplifier power gain is essentially a meaningless and non-useful quantity, because the load impedance is vastly different than the input impedance). To use your examples: To simplify and look at it another way, suppose the voltage gain is 10 dB, or a factor of 10. Consistent with the formulas I stated previously, a voltage gain of 10 db corresponds to a multiplication of the voltage by a factor of about 3.1623, not by a factor of 10. And **for a given load impedance** (note the use of that expression in my previous post) that corresponds to a multiplication of power by a factor of 3.1623 squared, which is 10, and which per the formulas I stated previously is also 10 db. Take a common 100 W amp with input sensitivity of 1V for the full 100W output. Power is V squared over R, which is 100W. At 8 ohms, V squared is 800. Take the input V of 1, and you get a V squared ratio of 800. The power gain in dB is the log of 800=29, but the voltage gain is the square root of 800 whose log is 14.5 dB. Per the relation P = (V squared) / R, the voltage corresponding to 100 watts into an 8 ohm resistive load corresponds to the square root of 800, which is about 28.28 volts. Voltage gain that would result in an output of 28.28 volts in response to an input of 1 volt is a voltage gain of 28.28x. Per the formula I stated in my previous post 20 x log(28.28/1) = 29 db, not 14.5 db. The power gain in that particular situation (involving an amplifier) would be a number that is completely different, and that has essentially no practical usefulness, because the input impedance is very different (and presumably vastly higher) than the 8 ohm load impedance. Again, note the reference in my previous post to "for a given load impedance." Due to the presumably very high input impedance, the input power would be very small, and would be dependent on the specific input impedance of the particular amp, and its relation to output power would be of little or no interest. The bottom line, again, is that for a given load impedance the number of db corresponding to a given voltage ratio is the same as the number of db corresponding to the resulting power ratio. Regards, -- Al |
For "slam" in classical music, one only need try The Rite Of Spring by Igor Stravinsky... I suggest the version conducted by Pierre Boulez, but there are many excellent recordings out there...
Or listen to some of the more dynamic movements of Gustav Mahler’s symphonies.... Particularly 2nd, 3rd, 5th, 6th, 7th, and 9th...
WC, you still might not end up liking the music, but as a whole, and The Rite Of Spring in particular, are unlikely to let you fall asleep any time soon.
Good suggestions, Guido. Another choice would be the Telarc recording of Stravinsky's "Firebird Suite," coupled with excerpts from Borodin's "Prince Igor," Robert Shaw conducting the Atlanta Symphony. A digitized version someone created from the LP can be downloaded here:
https://archive.org/details/StravinskyTheFirebirdborodinPrinceIgor-Telarc-Vinyl24-bit
That recording of the Firebird Suite may very possibly have the widest dynamic range of any recording I have ever heard, as particularly exemplified by the difference in volume between the whisper-like notes just prior to the start of the finale, and the concluding note of the work. Best regards, -- Al
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I haven’t posted in this thread for quite some time, as I haven’t had anything relevant to contribute. But I’ve been enjoying following WC’s journey, and I think his reports here are now being very nicely complemented by the videos. And by what I consider to be the excellent narration he provides in them.
My only suggestion at this point is for him to consider purchasing a tripod, and a phone holder that can be mounted on it. B&H Photo Video is a great source for such things, and pretty much all things related to pro video and pro audio. (I have no affiliation, other than as a customer).
Regarding the visual quality of the videos, while I’m sure most here realize this I’ll mention that viewers should check the playback format under the gear-shaped icon at the lower right corner of the playback window, and make sure it is set to the highest quality setting that is offered. At my location, with a very high speed Internet connection, the highest setting that is listed is 2160p for the first video and 1080p for the second video.
Regarding the possibility that was suggested of obtaining a 4K camera, I’ve done a good bit of editing of 4K material for amateur purposes, and I can say that in addition to the camera a very powerful (and likely expensive) computer is necessary to edit 4K material in a reasonable manner. And that is only somewhat less true if low quality "proxy files," generated either by the editing software or by some cameras, are used for most of the editing process. Of course, if the video and audio file captured by the phone or by a camera is directly uploaded to YouTube that issue is avoided, as is the extensive learning curve that good editing software usually entails (I use Vegas Pro). But if WC were to improve the sound capture by utilizing mics and a recorder that is separate from whatever is capturing the video that in itself would necessitate editing, to combine the video with the separate sound capture. (Video cameras of course can usually accept external audio inputs, but the audio quality they provide is usually inferior to what a quality sound recorder would provide).
And regarding sound recorders I have no experience with the Zoom H4n that was suggested (ca. $200). But at a considerably higher price I can say that a Sound Devices MixPre3ii or MixPre6ii, coupled with a pair of good quality condenser mics would provide great results. I’ve been very pleased with the Audio Technica AT-4051b mic, costing about $600 each, and I’m sure the somewhat more expensive Neumanns mentioned by Viber6 are excellent as well. Unfortunately, though, two of those mics plus a MixPre, mic stands, memory card, batteries, cables etc. would run well over $2K.
WC, keep up the good work!
Thanks and regards,
-- Al
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In professional circles, it is well known that directional cardioid mikes give better clarity and focused imaging.
That has been my experience as well, in an amateur circle :-) And that figures to be especially true in a home listening room, with reflected sound arriving at the mic from all angles, and with not a great deal of delay relative to the direct arrivals. Like Viber's KM184, the Audio Technica AT-4051b mic I mentioned earlier ($600 at B&H) is a cardioid condenser type, in this case having a diameter that is a bit larger at 0.83 inches. Regards, -- Al
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