Parallels Pros And Cons
Apr 22, 2021 A common feature of all four multiverse levels is that the simplest and arguably most elegant theory involves parallel universes by default. To deny the existence of those universes, one needs to complicate the theory by adding experimentally unsupported processes and ad hoc postulates: finite space, wave-function collapse, ontological.
- Parallels Pros And Cons Free
- Pros And Cons Meaning
- Parallel Computing Pros And Cons
- Parallel Voting Pros And Cons
More often than not a question pops up in our forum about speaker impedance and the result of connecting multiple speakers to a single amplifier. Thus we have prepared this introductory tutorial to help clear up some of these questions.
- Although parallel downloads can help reduce the time it takes to download resources/load resources on pages, there are a number of cons you must consider before using parallel downloads across domains on your site. Below are the main cons to consider.
- Updated for 2021! Complete list of pros and cons of Parallels Access from real users of the solution.
- With all of the capabilities of Parallels Desktop for Mac, you won’t believe how easy Windows is to use, especially on your Mac. If you’re looking for the best Windows solution for your Mac, you’re looking for Parallels Desktop for Mac. Parallels Desktop for Mac Review Pros and Cons.
The most common ways of hooking up more than one speaker to an amplifier channel are:
- Series Connection
- Parallel Connection
- Series-Parallel Connection (for more than 2 speakers)
There are pros and cons to each method which we will discuss herein.
To understand the differences, we must first explore the very basic principle of how electricity flows through a circuit.
Ohms Law: V = i * R where V = voltage, i = current, R = resistance (1)
A loudspeaker isn't a simple resistance because it is an electroacoustical-mechanical device which is usually governed by a complex passive crossover network comprised of inductors, capacitors and resistors. Thus the speaker system presents a complex impedance which varies with frequency and power level. 'Complex' here means impedance is a vector quantity possessing both phase & magnitude.For simplicity sake, we shall model our system's impedance magnitude only, ignoring phase . As an example, let's look at an impedance curve (or modulus of impedance) of an actual loudspeaker (the Onix x-ls).
Graph 1: Sample system modulus of impedance
The impedance minimum 0f 6.56 Ω at 42 Hz indicates the vented box tuning frequency. There are two other local minima, found at 164 Hz (6.386 Ω) and 3.4 kHz (4.97 Ω). That the first two minima are proximal in magnitude indicates an efficient reflex action. The large impedance peak, found at ~ 850 Hz arises as a result the interaction of the crossover network's high- and lowpass sections, setting up a parallel resonance. The impedance phase swings between +39° and -54° across the audible spectrum. With a lowest magnitude minima value of 4.97 Ω, the system nominal impedance (per IEC standards) value would be 6 Ω.
Series Connections Basics
Schematic 1: Series Circuit
As you can see in our diagram above, we have connected Zspk1 and Zspk2 in series with our amplifier (Vs). Using Ohms law (1) we can calculate the following relationships:
Equivalent Impedance also known as the Thevenin Impedance where we short our voltage source (in this case our amplifier) to calculate the total load it will see from our two speakers connected in series.
Zeq = Zspk1 + Zspk2 (2)
For simplicity, we shall use identical speaker loads from the speaker we showed in the above example.
Hence, Zspk1 = Zspk2
Zeq = 6 + 6 = 12 ohms
Thus by connecting two speakers in series, the amplifier now sees double the load impedance. But how does this translate to power delivery?
In a series circuit, there is only one path from the source through all of the loads and back to the source. This means that all of the current in the circuit must flow through all of the loads and the current though each load is the same.
To calculate voltage drop through each load, we apply Ohms law: (1)
Vspk1 = i * Zspk1
Vspk2 = i * Zspk2
Next we apply Kirchoff's Voltage Law (KVL) which dictates the sum of the voltages within a circuit must equate to zero.
Thus we get the following relationship:
Vs = Vspk1 + Vspk2 or Vspk1 + Vspk2 - Vs= 0
Let's assign some arbitrary numbers to solve for the variables in our equations.
Vs = 10V
Zspk1 = Zspk2 = 6 ohms (as per our speaker example)
First we must solve for current in the circuit so we can calculate our voltage drops to each load.
Using KVL we write the following mesh equation:
-10V + i*(6) + i*(6) = 0
Solving for I, we get: i = 10 / 12 = 0.83A
Now we can solve for our load voltages using Ohms law (1):
Vspk1 = i * Zspk1 = 0.83A * 6 ohms = 5V
Vspk2 = i * Zspk2 = 0.83A * 6 ohms = 5V
Of course a more simplified method known as the Voltage Divider principle can be used for calculating voltage across loads in series circuits. Here is how we can quickly solve for Vspk2:
Voltage Divider Relationship: Vspk2 = Vs * (Zspk2) / (Zspk1 + Zspk2) (3)
Using KVL we check to see if the sum of our load voltages equal our source so that the total voltage summation in the circuit equates to zero.
-Vs + Vspk1 + Vspk2 = 0
-10 + 5 + 5 = 0
as you can see we correctly calculated our circuit voltages as KVL was satisfied. Working up a circuit model using Electronics Workbench (EWB) confirms this.
Schematic 2: Series Circuit
But what about power?
To calculate our power to each loudspeaker, we must first develop a relationship for power.
Here are three commonly used equations: P = V * i ; P = V^2 / R or P = i^2 * R (4)
The Handy Dandy Ohms Law Pie Chart
Since we calculated all of our circuit voltages and current, we can find power with either of the above equations. Let's use P = V^2 / R only we shall represent R as Z for our loudspeaker magnitude.
Pspk1 = Vspk1^2 / Zspk1 = (5V)^2 / 6 = 25 / 6 = 4.17 watts
Pspk2 = Vspk2^2 / Zspk2 = (5V)^2 / 6 = 25 / 6 = 4.17 watts
Ptot = Pspk1 + Pspk2 = 4.17 watts + 4.17 watts = 8.33 watts
If we were to rework this example for just one 6 ohm loudspeaker connected to our amplifier, we would have seen the following power delivery to the loudspeaker:
Pspk = 10^2 / 6 = 16.67 watts since all of the voltage from our amplifier would have been delivered to the single loudspeaker load. Once again our model confirms this.
Schematic 3: Single Load
Thus connecting two speakers in series resulted in ½ the power consumption of just one speaker directly connected to our amplifier. This makes sense since the amplifier is now seeing double the load impedance and delivering only ½ the current.
So how does this equate to sound pressure levels?
Since we connected two identical speakers in series with our amplifier, each speaker only sees half the voltage drop across it thus as a result will see only 1/4 the power delivered to each speaker compared to a single speaker connected to our amplifier. The equivalent SPL now produced by each speaker is 6dB lower than if a single speaker were playing off the amplifier, for a combined overall -3dB drop. However, running two speakers effectively doubles the volume displacement compared with that of one speaker. Thus playback through the two drivers results in a 3dB gain. Adding this to the 3dB drop previously mentioned and the net overall sound pressure level will remain unchanged. Thus, playing two identical speakers connected in series off of a common amp (as opposed to playing just one speaker off that amplifier) results in no level drop, when compared to the single speaker case. This analysis, of course, ignores mutual coupling and any room-induced acoustical artifacts. However, if the speakers connected in series are not co-located and summing perfectly in the room, the net SPL would likely be up to -3dB lower than playing a single speaker off the same amplifier. The net SPL product in this case has a dependent relationship on distance between the speakers and frequencies they are destructively interfering in the room.
Modeling both a single-driver system as well as a series-wired, dual-driver system we see the dB spl plots are virtually identical.
Graph 2a: Single driver, system model: Amplitude response. dB spl @1m/2.828Vac drive level, ref. to 20 μPa.
Graph 2b: Dual- driver, series wired system model: Amplitude response. dB spl 1m/2.828Vac drive level, ref. to 20 μPa.
What is data transmission?
Data transmission refers to the process of transferring data between two or more digital devices. Data is transmitted from one device to another in analog or digital format. Basically, data transmission enables devices or components within devices to speak to each other.
How does data transmission work between digital devices?
Data is transferred in the form of bits between two or more digital devices. There are two methods used to transmit data between digital devices: serial transmission and parallel transmission. Serial data transmission sends data bits one after another over a single channel. Parallel data transmission sends multiple data bits at the same time over multiple channels.
What is serial transmission?
Parallels Pros And Cons Free
When data is sent or received using serial data transmission, the data bits are organized in a specific order, since they can only be sent one after another. The order of the data bits is important as it dictates how the transmission is organized when it is received. It is viewed as a reliable data transmission method because a data bit is only sent if the previous data bit has already been received.
Serial transmission has two classifications: asynchronous and synchronous.
Asynchronous Serial Transmission
Data bits can be sent at any point in time. Stop bits and start bits are used between data bytes to synchronize the transmitter and receiver and to ensure that the data is transmitted correctly. The time between sending and receiving data bits is not constant, so gaps are used to provide time between transmissions.
The advantage of using the asynchronous method is that no synchronization is required between the transmitter and receiver devices. It is also a more cost effective method. A disadvantage is that data transmission can be slower, but this is not always the case.
Synchronous Serial Transmission
Data bits are transmitted as a continuous stream in time with a master clock. The data transmitter and receiver both operate using a synchronized clock frequency; therefore, start bits, stop bits, and gaps are not used. This means that data moves faster and timing errors are less frequent because the transmitter and receiver time is synced. However, data accuracy is highly dependent on timing being synced correctly between devices. In comparison with asynchronous serial transmission, this method is usually more expensive.
When is serial transmission used to send data?
Serial transmission is normally used for long-distance data transfer. It is also used in cases where the amount of data being sent is relatively small. It ensures that data integrity is maintained as it transmits the data bits in a specific order, one after another. In this way, data bits are received in-sync with one another.
What is parallel transmission?
When data is sent using parallel data transmission, multiple data bits are transmitted over multiple channels at the same time. This means that data can be sent much faster than using serial transmission methods.
Pros And Cons Meaning
Given that multiple bits are sent over multiple channels at the same time, the order in which a bit string is received can depend on various conditions, such as proximity to the data source, user location, and bandwidth availability. Two examples of parallel interfaces can be seen below. In the first parallel interface, the data is sent and received in the correct order. In the second parallel interface, the data is sent in the correct order, but some bits were received faster than others.
Advantages and Disadvantages of Using Parallel Data Transmission
The main advantages of parallel transmission over serial transmission are:
- it is easier to program;
- and data is sent faster.
Although parallel transmission can transfer data faster, it requires more transmission channels than serial transmission. This means that data bits can be out of sync, depending on transfer distance and how fast each bit loads. A simple of example of where this can be seen is with a voice over IP (VOIP) call when distortion or interference is noticeable. It can also be seen when there is skipping or interference on a video stream.
When is parallel transmission used to send data?
Parallel transmission is used when:
Parallel Computing Pros And Cons
- a large amount of data is being sent;
- the data being sent is time-sensitive;
- and the data needs to be sent quickly.
A scenario where parallel transmission is used to send data is video streaming. When a video is streamed to a viewer, bits need to be received quickly to prevent a video pausing or buffering. Video streaming also requires the transmission of large volumes of data. The data being sent is also time-sensitive as slow data streams result in poor viewer experience.
QUANTIL provides acceleration solutions for high-speed data transmission, live video streams, video on demand (VOD), downloadable content, and websites, including mobile websites. If you want to know more about how we deliver data, you can tweet your questions to our team at @Team_QUANTIL.
Parallel Voting Pros And Cons
Laura Mellon joined QUANTIL in April 2016 as the Content Marketing Manager. She works with internal and external subject matter experts (SMEs) to develop informative content about CDN products.