Pradeep

On 1/2/2021 at 6:09 PM, SME said:

I can't recall where, but I have read that many brand new electronic components (capacitors among some things) do have a break-in process, but it is very rapid, essentially done after the component has been charged for a few seconds.  Distortion of 0.1% isn't exactly high---*it* might be slightly audible in an amp depending on the particular nature of it---but if the problem vanishes after pushing it briefly, it doesn't seem like anything of much practical concern.

However, this does suggest that Hypex is not testing the finished components at their specifications before shipping them.  I'm rather surprised, as this doesn't seem like a difficult or expensive thing to do.

Unrelated to this, I know that Hypex amps will not accept a signal from the Motu 16A audio interface (or others in the same family) that I use together with a PC for many channels DSP.  Something about how the 16A analog outputs are driven just doesn't jive with the Hypex amps.  I don't really understand it, but it was reported on in detail here among other places.

Lastly, IIRC someone I know managed to get a Hypex amp (one with builtin DSP, I believe) to go unstable (i.e. noise at full blast) by feeding it high-level ultra-low frequency signals.  I believe he first implemented the ULF boost via the built-in DSP and later used an external DSP, and both caused the unit to go bananas.  I'll see if he wants to come onto the forum and share his experience, so you can hear about it first hand.

SME, did you ever resolve the issue with the 16A outputs and the Hypex amps? I thought I read someone had done a simple mod on the amp inputs to filter out the rf noise that causes the issue. Commercially the only one doing RF filtering on the inputs that I know of is March Audio, I'd rather get a Buckeye NC252/NC502 based amp for max bang for buck.

15 hours ago, SME said:

Interesting.  Does the AVR do bass management on those channels or just pass the content through?  Or can one choose between "small"/"large" to enable/disable bass management for Atmos speakers?  It'd be weird if they just let the content go through.  I'm sure that'd cause a lot of distortion, wouldn't it?  I hope they at least provide the "large" option being that all my bass management is done downstream of the AVR with the matrix processing to optimize the crossover  EQ and delay of each channel across the available subs.

I'll also be feeling the pain of only 16 output channels on my 16A if I push to Atmos.  My front stage speakers are 2-way active, and I am using 4 different sub channels.  I'm thinking I may end up doing 7.x.2 with 6 outputs used for the fronts, 4 used for the surrounds, 2 for the ceiling speakers, 3 sub channels and 1 channel for the Crowson.  That's a painful compromise to make.  At least I don't need 4 ceiling speakers.  It just doesn't work with the room, and with only one row of seats and the quality of phantom imaging I am able to get after optimization, 7.x.2 will probably be great.

Thanks, but my point was actually that I *can* compromise deeper extension, and I want to because that's the only way to really get the most efficiency in the upper bass / low mid frequencies where I typically need headroom for EQ boost.   These speakers go up near the ceiling, which provides a lot of extra boundary gain below the suckouts.  All of my speakers, which are placed near walls, are EQed down quite a bit below 120-150 Hz or so.    I don't like spending $$$ on amp power, so I want a coaxial with high efficiency, low mass, and moderate displacement capability.  Most coaxials are designed to be used as full-range speakers, and therefore give up efficiency for extra displacement and/or bass extension that I don't need.  Some others are strictly mid-range drivers and don't have enough displacement.

The T/S specs on that 15" look real nice.  AVSForum appears to be broken for me ATM.  OTOH, I was looking at a 10" with similar efficiency, albeit less extension.  I think it was the B&C 10CXN64.  Hopefully I'll be able to find someone who sells it when the time comes.

Processors with Atmos/DTS:X allow you to set the heights as small with variable crossover or large, like the bed channels. So no problems obtaining full range signals for downstream processing.

@SME

I know you were looking for a high efficiency surround speaker that wasn't compromised into trying for deeper extension, looks like these might be what you were looking for?

https://www.avsforum.com/forum/155-diy-speakers-subs/1514289-coaxials-another-diy-group-project.html

"15" Specs: Fs: 39.3hz QM: 12.12 Vas: 259.2 liters Cms: .249 mm/N Mms: 66.1 g SD: 856.3 cm^2 VD: 348.0 QE: .33 Re: 5.05 ohms Le: 0.60 mH Bl: 15.68 Tm QT: .33 SPL: 98.6 1w/1m Mmd: 51.7 grams"

On 1/17/2019 at 4:44 PM, SME said:

Dedicated subs for each Atmos output channel?  That's pretty ambitious!  I can't recall, but I thought Atmos heights were specified to be limited bandwidth?  Assuming they were, I also don't recall if the bass management was supposed to be done by the playback processor, the authoring tools, or by the mixers themselves.

Over on AVS BassThatHz routed the Atmos channels from MI: Fallout to his bed speakers and found extended bass present to at least 20 Hz. Apparently Atmos channels are capable of full range like the surrounds. It's tempting to treat them as just small effects speakers but clearly there's a lot of content there.

I won't be at the dedicated Atmos subs stage for a while, still need to save the pennies for a Motu 16A to take care of sub crossovers for all the beds first. Then I'll be out of outputs and will need to expand, perhaps a 24Ao as I won't need anymore inputs. Definitely not a cheap path but not approaching Trinnov pricing either.

Thanks for the explanation SME.  I'm working on deploying dedicated subs for all bed channels (and eventually heights), so that my sub out is just LFE, with no redirected bass. Goal is to be reference capable to at least 20Hz on all channels.

On 1/12/2019 at 11:49 AM, Joelmister127 said:

Ah I see, so do you think that is where the 3-5hz content is mostly? Probably to make the audience as shit scared as Tom Cruise was trying to get to the helicopter hahaha!

Honestly I'm not sure, choppers are usually around 7Hz, as you mentioned previously there were some moments where you can just feel pressure or a really quick pulse,  I didn't make note of exactly when those happened.

SME, are you boosting the low end with BEQ for those movies you mentioned? JW Fallen Kingdom needs a big boost down low to extract the deep stuff.

On 1/9/2019 at 12:58 PM, Ricci said:

Yep...I emailed Brian about the SP1-6000 plate amps a few weeks ago and he put me in contact with Justin. Brian says he still does consulting work for SP when needed but otherwise is retired. 

Someone over at AVS received an sp1-4k or 6k recently and looks like they are using an internal cover again on the plate models. Glad to hear Brian's potentially still got some input there even if he does spend most of his time sitting on a beach drinking rum now.

Best part of MI: Fallout to me was when:

On 8/7/2018 at 10:39 AM, Jesal said:

Wife is told it's only the left side, I need one for the right side. After her jaw dropped, she just said, OK sell your other speakers and you can build another sub. Wohooo

 

 

 

Well played:)

1 hour ago, SME said:

The implication is that good surrounds need bigger drivers, albeit light-weight pro-style drivers that have high sensitivity and modest excursion capability at the expense of bass extension.

Have you considered something like the 95db Volt 10lx? As you say the issue is the bass extension, I have a bunch of jbl 1214s I've been trying to figure out what to use for, one thought was to have 2 1214s supporting each volt and crossing over at 100Hz to the 10lx.  That should allow them to have much greater extension.

There was some posts from Erich over at AVS that mentioned a possible 12 or 15" coax a few weeks ago.

That's of course if you dont want to go with something shallow like a Titan for surround use.

The dcx2496 has some limitations. Three inputs being one. Can the Motu 24Ai be used to feed in analog 11.1 from a receiver and then output 11.1 back out after eq? Or do I need the Motu 24Ao unit for the analog output channels? Will be monitored/controlled via PC and prob jriver for the eq but would like to still be able to throw a 4k disk in the player and watch.

Edit to add: ok so the 16A can do 16 in and 16 out and is $1500, otherwise 24 in and 24 out with the 24Ao and 24 Ai for $2000.

Thanks minnjd

The blurays for 1 and 2 sounded pretty solid with a 15db low shelf at 20Hz. 

Then I played Star Trek 2009 with those settings, wife was not pleased when i went upstairs afterwards. Sounded tremendous in the basement I think I need to just mute the four um18s when shes home.

It was JP1, MrGrey posted the graphs from all four of the 4k releases on avs and 1 and 2 both have rapid rolloff starting at 30Hz. Moreso than the bluray versions. Maybe it can be recovered once you guys have done your magic 3 and 4 look pretty solid.

Glad you got a tingle Infrasonic

Got the 2496 hooked up, pc cable wont be here till tomorrow so I floundered around with the on unit controls. I think I've managed to get input A going to output 1 (S7201) and input B going to output 3 (gamma 21s), with outputs 1, 3 and 6 linked. I havent figured out multiple filters yet so I put a low shelf at 20Hz, 15db on output 1. Was watching the Jurassic Park 4k disk and really couldnt feel too much of a difference, but just put the Oblivion bluray on and holy crap I should have tried this sooner. Can't wait to get to grips with it more and be able to implement the eq as recommended. Im not running very loud on main volume so while theres significant excursion I'm not at the limits.

Thanks for doing this maxmercy.

Just joined, been contemplating this thread for quite some time and finally ordered a dcx2496 to implement the beq for lfe and center channels. Lfe is a PSA S7201 and two Reaction gamma 21s VNF, and i have two PSA S15s running as subs for the center channel with a 210C sitting on top. I also have four um18s in sealed 4cuft flatpacks and two berry ep4000s, hopefully I can use the third channel of the 2496 to implement eq for those.