Happy New Year!
My uncle and I are planning to build a HT setup for his living room. I have an idea, but would appreciate some advice before we begin.
The room is fairly large, around 5x7 meters with sloping ceilings - 2.7 meters high sidewalls and 4.7 meters to the sealing in the center. My idea is to build a 5.1 system with five channels, each with two Markaudio CHR-70.3s. The subwoofer I'm considering is a 2x8" tapped horn TH-SPUD clone.
I'd like to wall mount all five channels, but I'm not sure what would be the best design for these speakers. Sealed boxes would be easier to build and also better looking IMO (smaller). With two CHR-70.3s paralleled in a 16 liter sealed box I get 87Hz F3 according to WinISD. If I roughly double the size and make it vented I can reach 40Hz F3.
This leads me to the following questions:
By the way, I imagine the system will be powered by a 5 channel DIY class-D/T amp (probably Hypex or Hifimediy modules), and the subwoofer(s) will have it's own readymade power amp.
Thanks for the help!
My uncle and I are planning to build a HT setup for his living room. I have an idea, but would appreciate some advice before we begin.
The room is fairly large, around 5x7 meters with sloping ceilings - 2.7 meters high sidewalls and 4.7 meters to the sealing in the center. My idea is to build a 5.1 system with five channels, each with two Markaudio CHR-70.3s. The subwoofer I'm considering is a 2x8" tapped horn TH-SPUD clone.
I'd like to wall mount all five channels, but I'm not sure what would be the best design for these speakers. Sealed boxes would be easier to build and also better looking IMO (smaller). With two CHR-70.3s paralleled in a 16 liter sealed box I get 87Hz F3 according to WinISD. If I roughly double the size and make it vented I can reach 40Hz F3.
This leads me to the following questions:
- Would you recommend sealed or vented enclosures for the five channels? Or perhaps a combination of sealed and vented boxes, e.g. vented mains and sealed center and surrounds?
- I've read about people having phase alignment issues when mixing different enclosure types in the same system. Could this be a problem here? Tapped horn sub mixed with sealed/vented channels?
- The TH-SPUD subwoofer has a FR of 19-125Hz on the paper, but from other build threads I hear about some severe resonant peaks in the higher frequencies, which I believe need to be filtered out. If I cut the sub at say 90Hz could I then successfully cross over to sealed channels, which have an 87Hz F3, or is that pushing it?
By the way, I imagine the system will be powered by a 5 channel DIY class-D/T amp (probably Hypex or Hifimediy modules), and the subwoofer(s) will have it's own readymade power amp.
Thanks for the help!
Attachments
I think that sounds like a great setup and I think doing sealed all around is a great idea. Crossing over around 90hz or so would be great between the two. I personally prefer 80hz but don't know really how much of an audible difference it would make going to 90hz. Nice thing is that you can always experiment to find the best for your application. Also doing identical cabinets makes building them much easier and aesthetically would look cool as well 
Scott
Scott
Not much
But with room gain from wall mounting, actual response will likly be lower than simmed.
dave
Am I understanding you correctly if this means that the actual F3 will be lower than the simmed 87Hz? And does this mean that I should make the sub's high-pass filter at a lower frequency?
If possible I'd like to run all five channels without low-pass filters, meaning that the only crossover will be in the subwoofer.
The DSP /bass management in most typical HT receivers (and I would have presumed HT-PC setups) allow for much higher HP filtering to the mains and surrounds than 80-90 - often with different settings for each channel. When using even multiples of full-range drivers of this "weight class", I'd be inclined to set in the 100-120Hz range and gain as much excursion headroom as possible.
My thoughts exactly. There's so much manipulation that can be done with the AVR that the standard 80hz crossover point at least gives you a starting point and from there you can experiment with what works best in your room with your gear and to your ear.
Scott
Thanks for the comments.
This will be my first HT build so I don't know a whole lot about AV receivers. However, I'd like to keep the cost of the project as low as possible and avoid having to purchase an advanced and expensive AV receiver with 'auto setup' features.
My initial thought was to buy a cheap 5.1 decoder like this or this. Do you have recommendations for a good value surround decoder/preamp?
Another option would be to forget about the multichannel power amp project and instead spend the money on a integrated AV receiver. What are your thoughts on this?
This will be my first HT build so I don't know a whole lot about AV receivers. However, I'd like to keep the cost of the project as low as possible and avoid having to purchase an advanced and expensive AV receiver with 'auto setup' features.
My initial thought was to buy a cheap 5.1 decoder like this or this. Do you have recommendations for a good value surround decoder/preamp?
Another option would be to forget about the multichannel power amp project and instead spend the money on a integrated AV receiver. What are your thoughts on this?
Honestly, I'd go for a mainstream AV receiver - plug and play and silly good value for from under $400 to whatever you wanna spend - but note that none will include power amp for LF channel.
Member
Joined 2009
Paid Member
I bought a blu-ray player with 7.1 analogue outputs and then built my own amps to go on the outputs. No receiver was needed and I still don't use one. It has been fun, potentially gives more flexibility and future upgrade options for ultimate quality, but it's a longer journey til you get something up and running and you have to do the set up manually. Unless you want all of that, I'd suggest an all-in-one solution is the way to go too.
Don't rule out a used AV receiver - may allow you to get a better quality unit.
I agree with Chris - sub should be self-powered using an off-the-shelf plate amp.
Don't rule out a used AV receiver - may allow you to get a better quality unit.
I agree with Chris - sub should be self-powered using an off-the-shelf plate amp.
With the bass management in current HT receivers, and presumably your 7.1 blu-ray, HT PCs etc, the rather limited and generally poor quality XO built into most of the plate amps (I've tried at least 5 different types over the years) could be avoided altogether and go for something like Dayton APA150 or AudioSource Amp100 (most of these are bridgeable for more power into a single enclosure, but even with a mono LFE channel, I prefer multiples) .
Further, inside the bass driver enclosure has gotta be about the worst place in a home audio system to locate an amplifier - just ask the warranty repair technicians at your local high end audio / HT specialist - WTF happens when replacments for the onboard amp module of your $5000 XYZ are no longer available.
sorry, rant off
I picked up a used Rotel RB850 for $150 about 5 years ago and it's still working like a champ, which is more than I can say about the 3 Motorola HD/PVR boxes* or the LG Plasma that flamed out after 4yrs.
* at least Shaw has been good about replacing them without a quibble - it's good to know that a total monthly service bill of close to $200 (phone/TV/internet) will buy you that kind of service - don't ask my sister about Telus' Optik
Yes, I'd obviously need a seperate amp to power the TH-SPUD. I'm considering something like this, which should give me 1x800W into 8 Ohms.
Thanks for all the great advice! And it's good to hear that I don't need to buy separate electronic crossovers and plate amps with low-pass filters, since all this can be done with the AV receiver. I'll begin my research into this new area
Thanks for all the great advice! And it's good to hear that I don't need to buy separate electronic crossovers and plate amps with low-pass filters, since all this can be done with the AV receiver. I'll begin my research into this new area
... AV receiver. I'll begin my research into this new area
If you can find something with pre-outs (or looks easy to extract the pre-amp signals to the outside). Or at least the mains.
I've been looking at Pioneers, Chris has a Denon, Onkyos should be decent
dave
my sister inherited an Onkyo when her daughter "moved back home for a bit" and it certainly has a few features that my Denon lacks - but then again the reverse also applies - the Denon's Audysey with calibrated mic makes speaker set up so stupidly easy even I could figure it out first time around
we're certainly currently afforded an embarrassment of riches when it comes to affordable and user friendly HT gear compared to only 10 years ago (some of us have shoes older than that)
Sweet New HT Recievers
Best thing to hit the audio scene in a while. This was VERY expensive not long ago, in 2010 it entered the mainstream. It is now a silly good value as someone said earlier.
Picture Explaining MultEQ
I don't mean to seem like an Audyssey fan boy, but everyone NEEDS to know about this. I run the auto setup whenever I see one of these receivers that has the feature. People usually don't even know it's there. They are always very happy especially when their speaker placement sucks which is almost always the case. This calibration works on all channels independently including the sub woofer. Also configures time alignment and crossover settings which can be changed after the auto setup.
Best thing to hit the audio scene in a while. This was VERY expensive not long ago, in 2010 it entered the mainstream. It is now a silly good value as someone said earlier.
Picture Explaining MultEQ
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I don't mean to seem like an Audyssey fan boy, but everyone NEEDS to know about this. I run the auto setup whenever I see one of these receivers that has the feature. People usually don't even know it's there. They are always very happy especially when their speaker placement sucks which is almost always the case. This calibration works on all channels independently including the sub woofer. Also configures time alignment and crossover settings which can be changed after the auto setup.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.