Karaoke Setup with PA Speakers

yanguei

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Planning to setup an independent karaoke system ( only sharing the projector) from my HT setup. Budget around $5K.

I searched the history and the suggestions of using PA Speakers appeared a few times.

Will appreciate if bros can provide more detail

Hardware :
I would need Mixer/Processor, Amplifier if passive speakers, Speakers and mics.
HQ1. Other than Hung Brothers and City Music, any other recommendations?
HQ2. Any brand recommendation?

Source :
I need a karaoke player (correct naming?) that has HDD, subscription for new song download and can select song via IOS or Andrioid phone/tablet. Does not like remote or a big touch screen. So far I can only find Thunderstone KTV's K Bubbles Plus has these features.
Is there any other karaoke player that I can consider?

thanks
 

yanguei

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Due to space constraints, I can only have cabinet width up to 13" if install vertically or width up to 17" if placed horizontally.

Went down to City Music. A wide range of Electro Voice PA speakers. The 8" and 10" models fit my space need.

I also consider QSC K8.2. Good reviews on a few sites. Not sure where I can view this in Singapore.
 

wwenze

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Careful with installing horizontally - most PA speaks have horned tweeters for good horizontal dispersion but poor vertical dispersion, but that's for when they're standing upright.
 

mypillowtalks

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Behringer, electrovoice, jbl pro, wharfedale pro, yamaha, qsc, rcf, GRF(few years ago 7th month getai quite trending), turbosound, iva(msia), dbtech, fbt, das audio, b-52, l-acoustics, peavey, mackie, funktion-one, TOA, HiVi, and more i cant rmb.

Other than the brand, rmb to look at the series as well.

Passive is relatively lighter. Some are plastic casing while some are wood. I will go for passive because i prefer placing the amplifier in a well ventilated area, and if the amplfier spoil, i can get a replacement amp and retain the speakers. I have overheated the amplifiers in my active speakers a few times, mostly the transformer died of heat.

Currently im using a mix of passive wooden n active plastic speakers and subwoofers: wharfedale pro, jbl, kempton(sub brand by fbt), haven't spoil yet so never upgrade. They sound alright both at home, outdoor, and in larger indoor venues like Singapore Expo halls.

8" and 12" PA is more than enough for a normal hdb living room.

Yes i do find the qsc k series nice sounding n easy to work with. Why not consider getting the k12 and add in a k series subwoofer called the ksub.

Their ksub seems quite compact. Maybe u can put two ksub tgt for the lows. Good enough to make ur living room to be part time night club already.

K12 should be still hovering at $1k+ per piece? I saw someone selling second hand k12s, not sure if still available.

Also for the mixers, some professional mixer contains lots of effects but may not have that traditional karaoke "echo" type of effects. Maybe u need to take a look around. Also, some mixers may not have the key control that lets u tune pitch of the music in karaoke.

Sometimes too many speakers in a small room isnt always good as it increases the chance of feedback. Maybe u can look into an equaliser, and see if the shop can help u set up in ur house n mitigate the feedback using the eq.

It will be much better if u do not have neighbours to disturb. Sometimes very tempted to test exactly how loud these pa system can get, then neighbours come n knock on ur door. Because of the horn tweeter design, if ur speaker is angled slighlty facing out of the window, ur neighbors next block should have no problem hearing clearly.
Sent from The Magical Land Of Talking Pillows, Bolsters & Blankets; Far, Far Away Deep In Another Galaxy using GAGT
 
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yanguei

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Thank all bros that responded.

My living room is about 7m x 5m. Volume and long throw are not my main criteria. I am looking more for musical quality and warm.

After some researching, a reasonable pair of PA speakers will be between SGD2,000 to SGD4,000. I will set my budget around there.

Weight is not an issue as not moving them around. Will wood cabinet sound better than the plastic cabinet?

Can I use my hi-fi amp like Emotiva, Rotel or Cayin (Tube) to drive PA Passive speakers?

Can I use existing HT subwoofer for both HT and Karaoke?

For mixers, I am researching mixer with built-in feedback eliminator. Echo and key control less important than feedback eliminator. Of course have all 3 better. Alternatively, I will consider a standalone feedback eliminator.

Thank for the info that the shop might be able to help to set up the EQ.

I have 2 neighbors that share a wall and a floor with my living room. So loud output is not possible. Nevertheless, I do not sing loud. Actually mainly my wife singing Chinese songs.
 

mypillowtalks

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Thank all bros that responded.

My living room is about 7m x 5m. Volume and long throw are not my main criteria. I am looking more for musical quality and warm.

After some researching, a reasonable pair of PA speakers will be between SGD2,000 to SGD4,000. I will set my budget around there.

Weight is not an issue as not moving them around. Will wood cabinet sound better than the plastic cabinet?

Can I use my hi-fi amp like Emotiva, Rotel or Cayin (Tube) to drive PA Passive speakers?

Can I use existing HT subwoofer for both HT and Karaoke?

For mixers, I am researching mixer with built-in feedback eliminator. Echo and key control less important than feedback eliminator. Of course have all 3 better. Alternatively, I will consider a standalone feedback eliminator.

Thank for the info that the shop might be able to help to set up the EQ.

I have 2 neighbors that share a wall and a floor with my living room. So loud output is not possible. Nevertheless, I do not sing loud. Actually mainly my wife singing Chinese songs.

$2k -$4k/pair should get you a very decent pair of PA speakers.
But don't spend too big portion of the $5k budget on just speakers, most important is still the karaoke on demand player, without that there'll be no karaoke.

A small sized mixer cost only a few hundred dollars, a decent power amplifier may cost about $1k, a pair of PA speakers may cost $1-2k, wireless microphone may cost a few hundred dollars for normal ones, cheap ones also usable.

I still think it is important to go down to the shop and let them allow u to test out the speakers before buying, best if they have a microphone for you to test.

Very hard to say "warm" or "music quality" over the internet. Because how warm or bright really depends on the type of drivers used in the speaker, and how the speaker itself respond.

I have a speaker with High freq horns that favours frequencies from 1kHz and above, making it sound bright, so i used the equaliser to tune it to make it "warmer" and less harsh.

Also take note that some of the High Freq horns of PA speakers are very harsh sounding, it will be tiring to the ears after listening for long hours.
These may be good for clubs to reproduce the high harmonics for techno/dance music, but may not be suited for other applications. Best to listen personally.

-----

In my opinion, i felt that generally wooden loudspeakers sound better than plastic ones. But plastic loudspeakers still sound decent, not bad sounding.

The following is a very short video recording of how my plastic PA speaker sound at an exhibition. It is a typical plastic loud speaker with a 12" LF driver.

In the video, i am running a pair of 12" 2 way PA Speaker which are pole mounted on a pair of 18inch subwoofer.



It was recorded through a handphone, so it is not an accurate representation of how it really sound, it's just to give a rough idea.

Not sure if you can see the speakers, they are black and placed against the big black wooden board. The width of the board is about 10+ meters. A pair of 12" speaker w subs is good enough to fill this small indoor area with light music.

As the PA speaker is very sensitive, i do not need much power to produce the Sound Pressure Level (SPL) required.
----

Yes, technically you can drive PA speakers with audiophile amplifiers that you have, I remember amplifiers like emotiva, rotels, mcintosh have quite a bit of power with low Total Harmonic Distortions.

However, some may find that it is a 'waste' to drive PA speakers using audiophile amplifiers as high end audiophile amplifiers are built for high fidelity. In contrast, a cheap PA may not have as high fidelity as an audiophile speaker, then again, it is really up to the purpose and application, there's no harm trying n experimenting if done correctly, it is very fun.

Moreover, as PA speakers are more sensitive than some audiophile speakers, PAs will be easier to drive.

PAs have sensitivity of about 96dB/w/m and up, while some audiophile speakers have sensitivity at about 80+db/w/m (if i rmb correctly). In very simple terms, without considering too much factors, take it as with 1 watts, PA speaker with 96db/w/m can produce approx 96db at 1 meter (usually at a single frequency of 1khz). Thus people say PA speakers (or highly sensitive speakers) are "easier" to drive.

But these numbers are not always so accurate, especially when more frequencies are being input into the speaker.

Also, as most passive PA speakers use "speakon" connectors(some call it "professional twist and lock"), you may need to terminate one end of your cables to fit this "speakon" connector if your current speakers do not already use speakon.

In simple terms, it is just a connector type with electrical contact points being housed into a plastic casing.

Note: some of these speakon connectors/receptacles have 4 terminals to run 2 sets of wire in 1 connector (Note its technical name). 2 sets of wires will have 4 wires, or 4 poles

This is good when biamping a single PA speaker, some PA speakers can be tri-amped as well.

One thing to note if u intend to drive PA speaker with audiophile amps (applies to any amplifier as well) will be the impedance of the driven speaker.

Like many speakers, PA speakers can have impedance of 8ohms or 4ohms. If you want to use your audiophile amps to drive the PA speaker, best to check the specifications of the amplifier and see the output power vs impedance. Try not to spoil the amplifier as i believe the ones you can easily cost much more than the PA speakers.

Another thing to note will be the Headroom of your audiophile amplifiers. Karaoke is a "live system", the source of sound comes from the microphone. If one day your friends come over and scream loudly into the microphone while singing, the amplifier will try to amplify the loud screaming (think high signal level), and the resultant instantaneous power demand may be quite a lot.

If the amplifier doesn't have enough headroom to handle this transient peak in signal, it can result in a clipped signal (some call it "not clean" signal) being sent to the speaker, which will cause damage when done continuously.
(Not being able to keep up w the transient will also result in something called slew rate distortion)

Examples of continuous clipping will be: using an amplifier that does not have enough power and trying to turn up the volume till it sounds distorted. Or trying to sing karaoke with an amplifier that does not have enough power for the speaker to produce the desired loudness, but still turning up the volume till it distorts.

The following picture shows the "nameplate" of a typical PA speaker. A power rating of 300W continuous is quite normal for a not so high powered PA speaker. Note the speakon connectors, sensitivity, impedance.

9FFJYHB.jpg


Usually for a 300Watts continuous (or some say 300 Watts RMS), it is recommended to use an amplifier with 1.5x the continuous rating of the loudspeaker. i.e 300W x 1.5 = 450Watts. This will give it some slight headroom to handle the peak signal

For more demanding applications, people tend to use amplifiers with higher power rating for more headroom.

Of cos, another method to control this peak in microphone signal is to use a compressor like what nastromo mentioned.
There are standalone compressors that can be inserted(electrically, not physically) between the channels of the mixer, and also basic ones that are built into the mixer. By compressing, the peak signal, low level signal and transient will be lowered, resulting in a signal which is "smoother" n more uniform in terms of magnitude. Some describe it as "making the soft part loud and loud part soft."

Then again for home use, we may not need amplifiers which are too powerful.
The process of choosing and pairing an amplifier with a speaker may be a bit confusing to some, thus they will prefer to buy active speakers, as the amplifier has already been properly matched(hopefully) and built into the speaker by the manufacturer.

----

Yes, technically, HT subwoofers can be used with your PA system, but here is the part that gets a bit tricky.

For HT, the AVR have the "LFE/sub woofer" out. The AVR have crossover built-in to help to send the high frequency to the speakers and send the low to the subwoofer.

But for a traditional PA systems, there is no crossover built into the mixer, which means this job is not done automatically.

The output of the mixer is a full range "XLR Left and XLR Right". In a normal system, these output signal from the mixer will be sent to a crossover, and finally to the power amplifier.

Thus, you will require a crossover to properly integrate the HT subwoofer with the PA speakers.

Else if there is no intention to use a crossover, you can still run the HT sub, but rmb to set the low pass/high cut to the lowest freq respond of the PA speaker, or any other points which u prefer.

Some Active subwoofers with crossover built in will accept the full range signal and help to output the high frequency signal to the speakers.

From here it can be seen that a PA system is quite "modular" (external compressor, external crossover, external feedback destroyer, etc), there are many physical modules for specific applications that can be added in or taken out.

Due to the different types of crossovers, equalisers, amplifiers, compressors, other external modules, PA systems may be more troublesome(in some way ) to set up compared to a HT system; but the advantage is that these external modules in a PA system may offer more parameters to fine tune.

(Fortunately, some companies like dbx design products that take over the job of all these "external modules", some of such products will be the dbx go rack that nastromo mentioned. Im using the dbx driverack 260 myself.)

Also, as PA speakers can get very loud very easily, sometimes the PA speaker may "over power" the HT subwoofers. I usually run 2 x 18" subwoofers with a single 15" PA Speaker, else it is hard for the sub to "keep up" at high SPLs.

Then again, im aware that some HT subs can get very loud and dig very low, eg. the SVS PB13 Ultra, but i didn't get a chance to try out high power HT Subs with PA speakers. Maybe you should experiment with it. It is fun to try.

Also note that mainstream not so expensive PA subwoofers wont be able to produce 20hz at 110db like what ht subs can do. Though there are big sized horn loaded PA subs designed just to reinforce the lows, usually used in clubs/cinema.

---

Some mixers do come with "Feedback Detection", but not sure which one comes with eliminators.

The "Feedback eliminator" that you are talking about and what nastromo mentioned is the "automated" process of "eliminating feedback using an equaliser".
These feedback eliminators will automatically detect which frequencies are causing the feedback and automatically attenuate them.

Some of my friends felt that if you are already using an equaliser to attenuate the "feedbacking" freq(in other words "ring out" the room), there isn't really a need to use this automated feedback eliminating devices anymore (or vice versa).
But in my opinion, as long as both devices are not set to contradict each other's setting, using them together is possible as some of these "anti feedback" system have a "live mode".

"Live mode" means it continuously detect if there's a feedback, and if there is a feedback, it attenuate that freq automatically (for a short few seconds), while you are using the system.

The reason why this "live mode" exist to continuously detect feedback is because sometimes singers will hold the mic n walk around the performance location(eg stage), and this could induce feedback.

Im using a device similar to what nastromo recommended, he recommended the dbx gorack, im using the dbx Driverack 260

Here is what the "active feedback screen" looks like:

BJlO3Iq.jpg


Note: the "F" stands for fixed filters, while the "L" stands for live filters.

I hope it is not too confusing, i feel it is important to know these minor differences between audiophile/HT system and a Professional audio system, hopefully these will help u consider more when buying a PA system.

There are more details for karaoke stuffs to look at such as setting the gain of the mic and overall gain structure of the PA system to gain the signals at each stage to an acceptable level for the device at the subsequent stage, something similar to pre-amping the signals in an audiophile system

PA speakers are built to be loud as they need to reinforce the sound in a noisy environment(shopping center, outdoor, concert hall, cinema), so their purpose is slightly different from audiophile/HT systems.

Cinema also use PA speakers, such as: https://www.qsc.com/cinema/products/loudspeakers/screen-channel-loudspeakers/2-way-bi-amp/sc-322c/

The KOD system i will ask my friend to post here, or i will post after i get the info from him, that one im not familiar, i do more on the PA system side.
 
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yanguei

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Wow.. thanks for the great and detail information. Greatly appreciated.

Noted on spreading out the budget. Thanks for the tips. Should be able to increase the budget if required as the set is to be used by the CFO and her sisters.

-------------------

Speakers

Because of size restrictions, I have shortlisted the below speakers :
1. QSC K8.2
2. EV ZXA1
3. JBL AC18 (Wood)
4. Peavy RBN-110

Hopefully, I can get to audit all of them in SG.

------------------------

HT Amp vs PA Amp.

Thanks for the great info again. I think I will not use HT Amp. Will sell away the extra HT Amp or use it for bedroom music. Will look for PA Amp or PA Active speakers.

---------------------------


KOD Players

Karaoke players vary a lot. The main requirement is able to manage song queue via a tablet. So far in SG, I can only find Thunderstone has this feature. Found a few on Taobao but prefer to buy an electronic device with local warranty.

-----------------------------

Wireless mic. Most likely Sennheiser.

-------------------------

Mixer.

I will settle on dbx Driverack 260. Since it has feedback eliminator and can do the crossover to subwoofer.

The dbx Driverack 260 has 3 XLR input. So 2 for mic and the other for the Karaoke player?

--------------------------------

Subwoofer

I have 2 Rymthik E15HP. I do not have space for another subwoofer. So my options are

1. Use the 2 Rymthiks for both HT and PA. Just need an XLR or RCA converter as I did not order my Rymthiks with XLR options previously.
2. Replace one Rymthik with a PA Subwoofer.

Will prefer option 1. And now seems a possibility. I will not be turning on the AVR while doing Karaoke. So I think it is safe to share the subwoofer.

I will cross over at 60Hz. 80hz if I can find smaller PA speakers.


----------------------------
 

mypillowtalks

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Wow.. thanks for the great and detail information. Greatly appreciated.

Noted on spreading out the budget. Thanks for the tips. Should be able to increase the budget if required as the set is to be used by the CFO and her sisters.

-------------------

Speakers

Because of size restrictions, I have shortlisted the below speakers :
1. QSC K8.2
2. EV ZXA1
3. JBL AC18 (Wood)
4. Peavy RBN-110

Hopefully, I can get to audit all of them in SG.

------------------------

HT Amp vs PA Amp.

Thanks for the great info again. I think I will not use HT Amp. Will sell away the extra HT Amp or use it for bedroom music. Will look for PA Amp or PA Active speakers.

---------------------------


KOD Players

Karaoke players vary a lot. The main requirement is able to manage song queue via a tablet. So far in SG, I can only find Thunderstone has this feature. Found a few on Taobao but prefer to buy an electronic device with local warranty.

-----------------------------

Wireless mic. Most likely Sennheiser.

-------------------------

Mixer.

I will settle on dbx Driverack 260. Since it has feedback eliminator and can do the crossover to subwoofer.

The dbx Driverack 260 has 3 XLR input. So 2 for mic and the other for the Karaoke player?

--------------------------------

Subwoofer

I have 2 Rymthik E15HP. I do not have space for another subwoofer. So my options are

1. Use the 2 Rymthiks for both HT and PA. Just need an XLR or RCA converter as I did not order my Rymthiks with XLR options previously.
2. Replace one Rymthik with a PA Subwoofer.

Will prefer option 1. And now seems a possibility. I will not be turning on the AVR while doing Karaoke. So I think it is safe to share the subwoofer.

I will cross over at 60Hz. 80hz if I can find smaller PA speakers.


----------------------------

About Mixer & DBX Driverack 260

Ok I think I will talk about mixer part first as I might have caused some confusion on that part.

1. The DBX Driverack 260 is not a mixer.
The KOD and microphone used for singing should not go into the DBX

2. A Mixer is a hardware that mix different signals into a combined signal.
For the case of karaoke, the different signals that the mixer will mix includes: Signals from Microphones or Signals from the KOD player.
Therefore stuffs like Microphones, KOD, Music players or other source of sound should be plugged into the mixer.

3. The DBX Driverack 260 is a type of Speaker Management System.

Speaker management system can be described as an equipment that has the ability to manage and modify the signals, before distributing these signals to the different types of speakers(subwoofer is a type of speaker) in the PA system.

Some of the jobs that the Speaker Management System does includes:
(a) The job of the Crossover
(b) The job of the Equaliser
(c) The job of the Limiter
(d) The job of the Feedback Eliminator
(e) Other features

Therefore, the Speaker Management System is usually placed before the Power amplifiers or the Active Speakers. It has to be placed here because its job is to help distribute the correct signal to the correct speakers.

This also implies that the OUTPUT from the Mixer will go directly into the INPUTS of the Speaker Management System.

Now, in your post, you mentioned that the DBX Driverack 260 has 3 INPUTS, the Mixer will take up 2(Left Channel and Right Channel) of the 3 INPUTS on the DBX Driverack 260.

The Last INPUT of the DBX is meant for RTA Microphone. The reason for the RTA Microphone INPUT is because this particular model has the ability to do auto equalisation for the system based on what the RTA mic picks up. It is similar to the "Audyssey" in a HT set up.

Lastly, after all the words above, it is not compulsory to use a Speaker Management System in the PA system unless you need its features.

Which leads to the next point, what are the necessary equipments needed for Karaoke using PA system?

---End of mixer & DBX Driverack 260---

4. Different Setup of PA System with different equipments

4(a) The Bare Minimum
*Note that the amount of microphones depends on the amount of inputs on the mixer

ytrMfZ2.png


Mixer mixes the music n human voices, outputs to active speakers.

The mixer in the illustrations are normal mixers.
Note that some model of mixers are called "powered mixers" as they includes built-in power amplifier to drive passive speakers directly.

4(b)
*Same as before, note that the amount of microphones depends on the amount of available inputs on the mixer

*An equaliser has been added into the system.
In a PA System, the equaliser is a popular device to help eliminate feedback by attenuating the problematic frequency. The catch is that it requires some skills n experience in identifying these feedback freq, thus ask if the shop can help to set up and tune if u decide to add in an equaliser.

KHMStp7.png


4(c)
*Same as before, note that the amount of microphones depends on the amount of available inputs on the mixer

*Note that two subwoofers(It can be 2 of the E15HP or other subs) are added in. Also, in this scenario, i make use of the subwoofer's built in cross over.
MbEkYIZ.png


4(d)
*Same as before, note that the amount of microphones depends on the amount of available inputs on the mixer

*Note that the following picture is slightly different from 4(c).

In 4(c), all the signals go into the subwoofer, then go through the subwoofer's built in crossover, and finally to the Active speakers.

In 4(d), i included an External Crossover. All signal goes into the External Crossover. Then the appropriate signals are being sent to the speakers and subwoofers

pu9fj2t.png


4(e)

Finally, this will help to illlustrate what the DBX Driverack or any other Speaker management system helps to do.

Note that the external crossover and equaliser has disappeared. This is because both of their jobs are taken over by the Speaker Management System.

As mentioned in point 3 above, the speaker management system can do a lot of jobs.

IC3u3Pr.png


In summary, as mentioned in your first post, a set up like what is shown in 4(a) is the bare minimum needed for a Karaoke.

Yes, Since you already have two HT subs, can just use them, not compulsory to purchase a PA subwoofer with PA speakers.
Point 4(c) seems to be the cheapest way to integrate the subwoofers properly. There are other ways too, no right or wrong

Really depends on how you want to crossover the speakers, different people different way and also depend on the freq response of the speakers and subs. Must play around
 
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yanguei

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Hi mypillowtalks,

Great great thanks to the long and detail explanations. I understand much more.
---------------

4(e) and DBX DriveRack 260

After reading all the options, I will go 4(e) and invest on DBX DriveRack 260 (SGD1,002 at Swee Lee). The feedback eliminator, crossover and auto-equalization features are very helpful for a novice like me.

I also looking at the new model DriveRack Venue360 ( SGD 1,336 at Swee Lee). From prosoundweb ( I cannot post link yet) site, there are many other new useful features, faster processor and control via tablet and PC. it might worth to pay the extra SGD330.

------------------

RTA Mic

At Swee Lee site, I also saw DBX RTA-M Reference Microphone (SGD155). It is plug directly into the XLR without any wire. From HT, we always put the mic at the MLP. for PA, no need for equalization?

-------------------

Mixer

Back to mixer jungle. At Swee Lee Site alone, there are 66 options.
Any advice?


----------------------

Passive Speakers

Saw a lot of passive speakers at Swee Lee site. Martin Audio has 8" that fit into my space. Are they any good?

-----------------------
 

mypillowtalks

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It seems like the DBX Venu360 is very worth it since it can be controlled by a tablet, more use friendly. I did not use the Venu360 before. $1336 is very cheap, and it can do more than the DR260!
(I bought the DBX DR260 many years ago at $2k+ )

It will take some effort to learn how to use a Speaker Management System, and best to read the manual and see what each model can do or cannot do.

When first started, it may be difficult to set the parameters on the small screen using only the knob and the buttons. But no problem once u are familiar.

For the older DBX DR260 im using, it takes some effort to navigate through the menu using the knobs n buttons before i can do tuning on the EQ, the disadvantage of this is that i cannot tune the EQ immediately.

Also the Driverack have this "Subharmonic Synthesizer".
It helps to add in Low frequencies harmonics in real time to the existing sound. I think this will be good for HT subs as HT subs have lots of excursions to handle this.

There are people who are against using this feature for PA subs as PA subs have less excursions, and there are cases of driver popping out at very high volumes. I tried it on my PA subs(within its limits) once at an event, very addictive feature, some people walking by will stop and listen, can feel the air getting pressurised.


If you are interested in other alternative, Behringer also makes a similar product

Or Lake products

Oh and yes speaking of lake, lab gruppen makes powerful amplifiers, i think some HT guys use lab gruppen amps to power their HT subs. Another brand called PKN controls makes power amplfiers that runs on 3 phase power
----

Though i did not do it before, if needed, I will connect an XLR wire to the RTA mic, and place the mic at the MLP point for the Speaker management system to do the tuning.

Not sure if the physical size of the rta mic can fit the input plug directly.

Same as HT, there is a need for equalisation on the PA system, depending on the different venues they are installed in. Every venue will be slightly different. It is about sound waves after all.

Not so related:
One difference between PA at large venue and HT at home is the distance between the [Speakers and subs] and the distance between the PA and the audience. Because of the distance, sound wave will arrive at different place at slightly different time, thus time alignment and equalisation may be needed.

The next challenge will be that some audience will sit very near the speaker, some sit far away from the speaker, how the PA speaker is aimed is important. In outdoor venues wind speed may be a slight concern as well. This is too tough for me to learn also and not so related.

Fortunately at home, the speakers and subs and the MLP are somewhat near, but no harm to do auto equalisation.

However, some will prefer not to do auto eq, as they prefer to manually tune the equaliser for creative reasons. (eg. more bass, more mid, less highs, less lows, etc)
-----

For mixer wise, nastromo recommended two products, you can evaluate them and see if it fits what you need.

There are DJ Mixers and Mixers.
The DJ mixer can be viewed as a specially designed mixer for the DJ to connect their turntables and players. The DJ mixer has a crossfader for the DJs to mix two different music from two different channels. It usually feature ONE mic input for the DJ to say some stuffs to the audience
The DJ Mixer is not ideal for karaoke.

A DJ Mixer looks like this (the one on the left):
dh1pGW7.jpg




For Mixers, there are digital and analog mixers. I am slightly more familiar with the basic analog mixers.

pgmUe3R.jpg


It may look complicated at first, but in general it is just an array of input channels linked together.

In other words, it is made up of many of these:
VwUfROT.png
This is a top view of how 1 channel of an analog mixer will look like. Depending on the model, some may have more/less knobs to tune, some may replace the fader with a knob to make it more compact.

Some explanation:

Left is 1 Channel, Right is 1 Channel. Stereo (L&R Channel) will take up two channels on the mixer

I will start with the inputs (XLR and the "1/4 inch plug" below the XLR plug first). The 1/4 inch plug accepts Balanced (TRS) or unbalanced (TS) connectors. Anything that produce sound will go into the XLR or 1/4" inputs.

Next, Right up at the top, on top of the XLR, it is the "Send/Return" plug.
If connected, it allows the input signal to be SEND out to an external processor (such as compressor or other effects) and RETURN back to the mixer. If no connected, the input signal will flow directly down to the other knobs on this channel.

Below the 1/4 inch plug, the square button is the "Low Cut" button. This button activates the High pass filter for this channel.

For this particular model, the high pass is set at 75hz with a slope of 12db/oct i think.

Generall, adult males have voices of freq85Hz and up, so it makes sense to have the high pass of 75hz, making it useful when this channel is used for vocals. It is Not compulsory to use, depend on own preference. Useful to prevent the mic from picking up bass, or the rumble when our hands "handle the mic".

The knob below the low cut button is the gain knob. It adjusts the amount of pre-amp gain of the channel. Different microphones, guitars, instruments have different voltage levels. When these signals are being input into the channel, this gain knob helps to pre amplify the voltage level of these input signal.

Usually i will turn up this preamp knob as much as possible before clipping. A clean and strong input signal is important.

Can google PA system gain structure to read more. Youtube have videos also.

Next, after the input signal flows thru the preamp, it will flow into the internal compressor. Most eq hv built in compressors. Compressor compresses the dynamic range of the signal to give a uniform sound. Usually for vocals people set to 3:1 ratio for smoother voice.

Next will be the "EQ" section of the channel. Depending on the model, some model have different number of knobs. In this mixer, the midrange is controlled by 2 knobs - one gain and one freq. This allows the user to select the intended freq with one knob, and choose to gain/attentuate with the other knob

Below the "EQ" knobs it the "AUX" or Auxillary send section. These knobs control the amount of signal to be send to the auxillary outputs. One use of this auxillary output is to output signals to the monitor speakers (if connected).

The yellow knob control the amount of input signal on this channel to be send to the built in effect processor of this mixer. The effect processor have effects like reverb, echo, etc.

The knob below is the pan knob. It allows the the input signal on this channel to be "panned" to the Left output channel or Right output channel. Imagine if recording a violin on this channel for an audiophile recording, the pan knob can be used to pan the signal to the left, to create the soundstage that the violin is on the left.

The mute button mutes the channel. If the singer is not using the mic, can use this mute to temp mute the channel to prevent accidental pick up

The slider is the fader that controls the amount of input signal to be sent to the main output.
But realise there are 3 buttons at the side.

The first button is the "solo" button. When activated, only signal from this channel will appear at the main output.
In other words, there will be only one "solo" signal at the output.

This solo button is useful when adjusting the pre-amp, as the signal level of this channel will be reflected on the output led lights.

The "SUB" button does not stand for subwoofer, it stands for subgroup. Signal from this channel can be sent to a subgroup.

Eg, signals on channel 1 and 2 can be grouped into subgroup 1, and there will be another fader called sub 1 which controls the overall volume of all "subgroup1"

Finally, the "MAIN " button , when activated, signal from this channel will sent to the MAIN output.

Before buying a mixer, i will estimate how many inputs i will need.
Each microphone will take up 1 channel, and the KOD Player usually takes up 2 channels (Left and Right).

Note that some fader will control 2 channels, eg:
nZEkOKp.png

Note the bottom writes 9/10. the knobs n faders control both channels 9 and 10 simultaneously. the KOD player can be connected into channel 9 and 10 for easier control.

Lets say 4 friends wants to sing simultaneously, this requires 4 mics and 1 KOD player. 4 + 2 = 6 channels.

If you want to connect music from your PC into the mixer without unplugging the KOD, it will take up another 2 channels.
Total will be 8 channels.

This will help u determine how many channels you will need.

After determining how many channels, next will be to see what features are on the mixer. Some mixers feature processors from well known manufacturers like klark teknic, then it will cost more. Some mixers have high quality pre-amp and willl be more expensive

One way is to borrow a headphone and plug into the mixer. If use own headphone w 3.5mm, need buy converter to 1/4 inch. Then get the shop to borrow u a mic if possible. Turn up the preamp n turn on the mic, and see how it sounds, listen thru the earpiece to see if the hissing is excessively loud. Then speak into the mic n listen. Then turn up the effects n listen. Finally, see if they allow you to hook it up to the pa speaker and listen.

Sim lim tower has some prosound shops selling mixers n amps n speakers. Can go see. Can ask them demo also.

---
It will be good to listen to how the martin audio 8" sounds.
Is the martin audio u seen this martin audio?
Martin Audio is a good brand as well, quite expensive.

I saw before people using a china made "martin audio", same name but different from the one i posted.

Maybe I will compare it against the QSC K8.2 and the jbl ac18. Thr jbl ac18 looks good, the horn's dispersion angle is quite big all around
 
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yanguei

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Many great thanks again for the detail explanations!

-------------------------

Noted on the speaker management system options and considerations.

Will check with Swee Lee on using XLR mic for RTA when I visit them.

Which Swee Lee branch is the biggest with knowledgeable staff for PA?


------------------------


Mixer likely going Behringer X Air XR12 that was recommended by nastromo.


--------------------------


The Martin speakers are exactly from the linked that you stated. Not those Martin speakers in SLT.


----------------------------

Now left the with Karaoke Player. So far the option is only Thunderstone.
 
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yanguei

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Downloaded the QSC manual.
It has built-in features for ggd QSC speakers. That will make the calibration easier for me.
However not clear whether can roll off low frequency to certain channels for subwoofer.
 

mypillowtalks

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The TouchMix 8 seems to be a good deal with all its features.

You can don't buy the DBX DriveRack/Gorack first, and decide whether if you really need it in the future.

Method 1

Assuming you have the QSC K8.2, I think there is no problem with setting the crossover frequency.

1. The Left output of the Mixer can go to the Input of the LEFT QSC K8.2, and the Right Output of the Mixer can go to the Input of the RIGHT QSC K8.2. You will require an XLR Cable for this.

2. The QSC K8.2 has a "Pass Through" Output. This allows you to pass the Input signal through the speaker to other audio equipments, called daisy chaining.

You can use a "XLR to RCA Cable" to chain the signal from one of the QSC 8.2 to one of your subwoofers. Do the same for both the left and right.

At this point, all signals from the Mixer will go to your speakers and subwoofer.

3. From page 15 of the K8.2 Manual (Link to the PDF), the K8.2 has this "Sub Setting" to allow the speaker to be used with a subwoofer. There are a few High Pass Filter settings in the "Sub setting" on the K8.2.

For example if the "Sub setting" is set to 80Hz on the QSC K8.2, the LPF to 80Hz on the Rythmik Subwoofer can be set to 80Hz.

Method 2


An "1 to 2 XLR Split Cable" can be used on both the L & R Output from the mixer, so there will be Two LEFT SIGNAL and Two RIGHT SIGNAL. One cable from the Left will go to the Left QSC K8.2, and one cable from the left will go to the Left Subwoofer.

Use the "Subsetting" on the K8.2 to set the HPF and set the LPF on the sub accordingly.
 
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yanguei

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Noted the 2 methods. thanks.


Hmmm... with the same investment of around SGD1,500, I can either

a) TouchMix-8 is SGD1,450 at Luthermusic eShop

b) Behringer X Air XR12 is estimated SGD650
DBX DriveRack 260 is SGD1,002 at Swee Lee eShop


Does XR12 + DriveRack > TouchMix-8?
 
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