Pictures of your speaker system

mscott I notice you have a bunch of isolation transformers.. I'm thinking of dipping my toes in that pool for my front end dac and preamp.. do you use it for everything or just amps?

 

They're Electra 1028 Be2 in the low-luster walnut finish. It's $2K less than the high gloss finish. I really want to upgrade to a Sopra 2.0 but I have to force myself to wait until some debts are paid off.

 

@mscott58 - I am curious at what frequency you have the Sunfire Subwoofers crossover set.

Edit: Corrected mistakenly thinking Carver rather than Sunfire.

 

They look like these.
http://hometheaterhifi.com/volume_9_1/sunfire-subwoofer-junior-2-2002.html

 

Dino got it - they're Sunfire True Subwoofer Super Junior's (TS-8). Here's the link - http://www.sunfire.com/productdetail.asp?id=10. Unfortunately they're not made anymore. And while they're not Carver branded, Sunfire was one of Bob Carver's companies. I really like them for their form factor and power. I used to have a huge Paradigm sub that could also be used as a side table (the thing was huge) but I found it to be less "musical" than the Sunfires. Also I played around and was able to get better sound/imaging in my small room with the stereo subs. Lots of people will tell you that one sub is enough, but I found that the two smaller ones worked for me, especially in that space and with my room treatments. They also integrated really well with my Merlin TSM-MME speakers. Finally, you'll notice they sit on platforms. These are purpose-built stands for subs that acoustically decouple them from the floor. I had to do this after my next-door neighbor (connected brownstones) felt a little too much of the bass traveling into their house.

 

Dino - Great question, and I'll have to punt. All of my two-channel stuff is currently packed away awaiting the renovation of our new house to be completed. If I had to guess I'd say I set it around 70-80Hz (but that's just a SWAG) and was very careful to set phase and level to mesh well with the Merlin TSM-MME's and minimize standing waves in the room. I also marked the settings on the level carefully, as sometimes I would go all bass-head and pump it up, and then would soon regain some level of sanity and dial it back down to the measured optimum level.

 

@uncola - I did go a little crazy with my isolation transformers. I have one for each monoblock (tucked in the back) as well as one for the digital front-end (over to the right). I even had one for the subs (in the middle between the monoblocks) although I later took that one out, when I put in larger transformers for the monoblocks.

These Topaz units are also wired for balanced power, which is kind of fun to play with, but you have to know what you're doing. For those not familiar, balanced power splits the power across the hot and neutral lines, such that there is still 120V across the legs, but that one is +60V while the other is -60V. (versus the traditional +120V and 0V). The idea is that the "balanced" approach helps counter/cancel any line noise (and living in an older area of downtown Philly the power lines are not exactly pristine). There's a thread on isolation transformers and some talk of balanced power here on SBAF already (http://www.superbestaudiofriends.or...ration-surge-protectors-ups-yadayadayada.282/).

I found the balanced isolation transformers in my system helped make things cleaner and less background noise. And to be honest there's just the fun part of the DIY and getting to explain to people what balanced power is all about! Also, hunting for the bigger Topaz units was something I did on eBay for many years, as you can find some amazing deals on them when people sell off old industrial/lab equipment. I think I got one of my 2.4kV units for something like $50. In fact the shipping was more expensive than the transformer, as they are hefty chunks of metal. I even bought a 10kV unit that weighs over 100lbs, but I never got around the hooking that one up.

Cheers all

 

Exactly right!

 

Decided to make a dedicated listening room and go nearfield. Please note the obligatory sbaf laundry diffuser, tasty chocolate and Audio-GD phoenix hiding under the desk(don't bother i will still find and replace you). Still have allot of tweaking to do but so far it sounds quite good already, i'm enjoying the nearfield experience.

 

Here the new ones that I mentioned before..

Borrowed Yamaha P7000S for amp from our studio... 2 x 650W should be enough.



Goes down to 20hz too... I plugged one more port after that REW pic so it doesn't really drop that fast, currently using the free Mathaudio RoomEQ to fix that 200hz+ bloat, I've found it works very well... I'm also currenly building 8 x 115 litre helmholz absorbers to try to fix the 40-60hz issues.. (hehe the speakers are also about 115 litre each)

Sounds very nice and the directionality from large woofer and horn is quite obvious. Need to adjust the crossover a litle, not sure if I want highs to drop that fast.. also I probably have to EQ the bass level atleast +5dB up for my preference.

 

Nice DIY room treatments! What are those bass traps in the corner made of?

 

It's heat pipe insulation that local diyers found working good for the money (55€/$ per 1200x42cm). The shape and thickness make it good down to 60hz or so. Simple buy and forget it.
https://www.isover.fi/tuotteet/u-tech-pipe-section-mt-40

But a properly tuned resonator should be much more effective.. just have to glue together awful lot of boxes..

 

Nice! That's a great idea.

My DIY bass traps (as you can see in one of my prior posts in this thread) are made of 6" thick recycled denim insulation, sandwiched against a piece of stiff foam insulation and held in place with deer netting and burlap. In the upper corners I also have a triangle shaped piece of the same insulation/foam/netting.

Regarding the resonator idea, haven't seen the plans for what you're talking about, but I would be worried that the frequencies you're talking about might not be impacted by cardboard boxes (assuming that's what you mean). A lot of people suggest using foam egg-crates to tune rooms, but from what I've read, they aren't effective for the majority of the audio spectrum. You need something like the fiberglass insulation in the tubes you have, or rockwool insulation, or the denim stuff - something that has more density and mass to it. Again, that's based on what I've read and also tried personally.

See that you have anti-reflection panels on the side walls and ceiling as well. What are those filled with? Insulation as well? Or are they just pieces of foam? Hard to tell from the picture.

Have you read the book "Get Better Sound" by Jim Smith? (http://getbettersound.com/index.php) It covers a lot of this type of stuff.

Cheers and happy listening

 

http://www.mh-audio.nl/acalculators.asp#showcalc
https://www.gearslutz.com/board/stu...665657-diy-helmholtz-resonator-made-easy.html
etc.. gearslutz has lots of content for it.. but that's what I'm building, lots of airtight boxes with small holes on top..

 

Ah, that makes a lot more sense! And I assume that they meant 19mm thick particle board, versus 19cm. Never seen 7.5" thick particle board before.

 

Man those highs roll off something nasty. How are you measuring you system?

 

Calibrated UMIK-1. I think it looks "worse" than it sounds, it sounds fine actually. Some roll-off is generally even preferred, these speakers are effortless so volume turns up quite loud without noticing.. but I ordered some new caps to try to nudge the highs a bit.

 

Room treatment? Maybe it has done, but this casual mention by @atomicbob in the general advice thread deserves coverage on the speaker threads,

Audio is now available, video to come when ready.

 

Phase Technology PC 9.5 L/R, PC 3.5 Center, PC-Surrounds x 2 (not shown), SVS PC-13 Ultra, Pioneer Elite SC-55 Receiver. GIK room treatments; I've been working with REW as much as I can to smooth the response using the receiver's and sub's EQs, Got it close to +/-10db 20-20k on the L, C, & R anyway with 1/6 smoothing. I'll admit to cranking the sub about 5-10 db higher for listening after I get the flat response though.

Display is 7-8 year old Panasonic 54" VT25 plasma.

Non-dedicated room obviously. If it wasn't a rental I could do the treatments better with ceiling corner traps and a cloud trap.