My GR Research Super V system

danvprod · « **on:** 15 Jul 2017, 07:56 pm »

My GR Research Super V system:
As of 2018-12-01:

As of 2018-05-23:

As of 2018-05-07

As of 2018-05:

As of 2018-04:

As of Late 2017:

Room dimensions are 16’9” x 14’2” (small alcove in the back by the entry door to the room – 7’7’” x 2’2”, so the right side of the room is really 14'6") x 9’ tall. I leave the back door open because it lets the room depressurize quite a bite. It makes the left wall (looking towards the speakers from the listening chair) 12’ or so longer and moves the modal frequency away from the parallel wall.

Major Components:
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1. GR Research Super V speakers.
2. Rythmik Audio DirectServo A370PEQ amps to power the 12” SW-12-08FR subwoofers in the GR Super Vs.
3. Neurochrome Modulus-86 amplifier
4. PS Audio Stellar Gain Cell DAC
6. Single-ended ICs (Gain Cell -> A370s): Blue Jeans Cables LC-1s
7. Balanced ICs (Gain Cell -> Modulus-86) Zenwave D3
8. Speaker Cables: Signal Cable Ultra Speaker Cables 8'.
9. Power conditioning: P.I. Audio Group MiniBUSS.
10. Power cords: Triode Wire Labs “American 8” for each A370 amp, 8+ for Mod-86. P.I. Audio Group MPC+ PowerCon for MiniBUSS (Made by Dave). P.I. Audio Group DAC cable for PS Audio SGC.
11. Hubbell spec grade duplex HBL5262GY.
12. Custom made low amp shelf. MDF/Plywood sandwich, heavily braced and coated with Duratex.

Room Acoustic Treatments:
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1. GIK Soffit bass traps 4x on the front (1x 35” to account for shorter right wall vs. left wall). 1x on the back wall behind the listening chair.
2. GIK Bass Pillar trap above the soffit behind the listening chair.
3. GIK 244 bass traps (2 at first reflection points), 2 between speakers (behind curtains), 1 at second reflection point on the longer left wall.
4. GIK QRD diffusers behind the Vs on the front wall x 2.

Notes:
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I wanted to post about my system now that I have had a chance to get it set up and dialed in during the last year (Super Vs purchased in Feb 2017). The Super Vs were not my first open baffle speakers that I’ve tried out in my room but far and away the best. The Super Vs replaced a pair of Decware-modified Fostex full range drivers in MLTL enclosures and before that a tri-amped pair of JBL horns (2226 + 2445 + 2405s). Bass from the Super Vs is unlike anything I’ve ever heard, even more powerful than my JBL 2226 midbass drivers in large enclosures with DSP and EQ.

Since purchasing them, I’ve also made lots of improvements to the room with treatments. I have five GIK acoustics soffit bass traps and a bass pillar, which have been the biggest improvement I’ve made in my room by far. I have a set of GIK 244 at first reflection points, a pair between the two speakers behind a set of curtains, and a single on the longer left wall at the second reflection point. I also have a pair of QRDs by GIK behind the Vs on the front wall.

I’ve tried a number of speaker cables in my system. I had been using some DIY “white lightning” cables, built from instructions on 6moons. More recently, I switched to Blue Jeans speaker cables (Ten White) having also tried AntiCables in the process. I’ve also had the Decware Zen Styx cables, which were a bit too short, so I sold them. I am now using Signal Cable Ultra Speaker Cables.

I use a P.I. Audio group miniBUSS. I plan on getting an uberBUSS in the future and daisy chaining the two together.

Music that I listen to:
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Jazz, classical, modern and classic rock. CDs ripped to loseless files played back through the PS Audio DAC from my Mac Mini. I run a 15’ USB cable directly out of my Mac Mini and into the DAC.

Updates:
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1. Still want to add an Uber Buss for additional power conditioning before the MiniBuss.

Historical Notes:
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1. 7/29/2017. Noted changed power conditioning solution. AudioPrism Foundation III has been sold, CD player out of the system. P.I. Audio miniBUSS purchased with DH Labs power plus. Decware speaker cables have been sold because they are too short. Back to White Lighting and Ancor tinned copper cords. Updated picture of system. Spatial black hole generator removed from system.
2. 5/01/2018. Updated pictures of the system. New curtains that aren't as shiny and not as blue (these are actually pretty close to medium gray in color). The hypothesis is that if they are shiny and cool, the system will sound that way too. I want neutral to the side of warm (auditory/visual interactions at work!). Updated info about chip amp. Removed items that aren't in the system anymore.
3. 5/22/2018. Updated intro section. Changed things that are no longer in the system or sold. Made a large effort to simplify everything, prioritizing the reduction of anything that generates noise or heat. Vinyl system removed. Sutherland phono preamp sold. Rega RP3 traded towards PS Audio Stellar Gain Cell Dac. Extra Blue Jeans cables sold. Isolation transformer sold. CD player sold. Maple rack sold. New pictures of set and DIY amp/dac stand.
4. 5/22/2018. Historical equipment no longer in use in the system.
a. DACs: MHDT Paradisea+. Breeze audio USB to S/PDIF convertor.
b. Phono Preamps: Lounge Audio Mk III LCR, Sutherland Ph3D.
c. Preamp: McCormack TLC-1.
d. Turntables: Sony TTS 3000A with SME Series IIIs tonearm. AT 440MLa cartridge, Ortofon Quintet Blue MC. Rega RP3 with Elys2 and GrooveTracer.
e. Amps: Decware Mini Torii.
f. Racks: Salamander audio rack. Solid maple audio rack.
g. Acoustic treatments: RPG skyline diffusors. RPG BAD ARCs.

ebag4 · « **Reply #1 on:** 15 Jul 2017, 08:42 pm »

Beautiful system and setup Dan. I know you are getting some excellent sound.

Best,
Ed

S Clark · « **Reply #2 on:** 15 Jul 2017, 09:16 pm »

That is great rig you've got. And talk about bang for your buck! Nicely done.

poseidonsvoice · « **Reply #3 on:** 15 Jul 2017, 11:31 pm »

As much as I enjoy you purchasing and implementing treatments, I think the single most important improvement you have garnered from your system is the ability to make measurements in the low frequencies, learn from them, make adjustments and subsequently make improvements to your system because of them. It is a knowledge that you can take with you regardless of where your system goes from now and into the future

.

Best,
Anand.

danvprod · « **Reply #4 on:** 16 Jul 2017, 08:25 pm »

Some Sunday low-cost experimentation. I still struggle with the Vs presenting a stable center image and have been reading the various treads about equipment racks to the side vs. between the speakers. Seems like racks in the middle are especially troublesome when they are as tall as the tweeter. I'm experimenting with putting the amp on the floor. I don't have ICs long enough from my turntable to run on the sidewall of the room, so I am just first experimenting with my DAC next to the amp, where I do have a 15' S/PDIF cable that can feed it.

Pretty non-subtle improvement to the imaging and soundstage. Center image is apparent and soundstage is deeper. Much less confusing aurally to have the rack out from between the speakers.

Who else has tried this?

ebag4 · « **Reply #5 on:** 16 Jul 2017, 08:52 pm »

Lowering the equipment rack to about a foot off the floor made a significant improvement in imaging in my system as well.

Best,
Ed

gregfisk · « **Reply #6 on:** 17 Jul 2017, 05:42 am »

Quote from: danvprod on 16 Jul 2017, 08:25 pm

Some Sunday low-cost experimentation. I still struggle with the Vs presenting a stable center image and have been reading the various treads about equipment racks to the side vs. between the speakers. Seems like racks in the middle are especially troublesome when they are as tall as the tweeter. I'm experimenting with putting the amp on the floor. I don't have ICs long enough from my turntable to run on the sidewall of the room, so I am just first experimenting with my DAC next to the amp, where I do have a 15' S/PDIF cable that can feed it.

Pretty non-subtle improvement to the imaging and soundstage. Center image is apparent and soundstage is deeper. Much less confusing aurally to have the rack out from between the speakers.

Who else has tired this?

My rack is on the side wall, laid the room out from the beginning so I could do it that way. At my beach house I have a dining room table in between my speakers, it is a very small house.

It makes a huge difference not having something in between for sure, I would never go back.

Shakeydeal · « **Reply #7 on:** 17 Jul 2017, 10:56 am »

Beautiful system and room Dan. I see you are using an MHDT DAC as well. I have had a Havana for over 5 years now and have not felt the need to do anything different. It just plays music.

Shakey

danvprod · « **Reply #8 on:** 17 Jul 2017, 12:28 pm »

@Shakey -- love my MHDT! I agree with you, it just works and plays music. No thoughts to upgrade other than maybe upgrading the tube at some point from stock.

To those that have moved their rack from out between the speakers: how do you deal with the long ICs? I need at least 15' to get from my amp to the rack following the wall to the left of the speakers (the rack is directly behind me to the left). The Decware amp is not perfect here, since it has two inputs and volume controls. It's prob better to also move the amp to the rack and run both long ICs and long speaker cables, although I would need ~ 25' runs to the right speaker and right A370 amp.

The other option I have considered is putting the gear in the closet behind me (would be a challenge but I could do it) and then running cabling to to the right side of my room outside my room and making an input box in both the closet and on the right wall. That would be fun and clean things up a lot.

Getting some relatively inexpensive long ICs is the first step here. I think that 15' Blue Jeans cables have low enough capacitance to not cause any HF rolloff, plus since the volume controls are on my amp, the signal to the amp's inputs is line level and not attenuated.

danvprod · « **Reply #9 on:** 23 Jul 2017, 01:22 am »

Local CL find today: A McCormack Line Drive TLC-1 preamplifier. This unit has a buffered output and passive outputs, which lets me do two important things:

Run my Decware amp powering the P.Audio drivers with the fMod 80 Hz HP filters, keeping low frequencies out of the co-ax amp and letting me get a dB more or two out my 4 watt amp.
Balance the whole system with measurements and then adjust the volume with a single knob.

I still am having an issue with the right HF driver (see my other thread), but I am hoping a diaphragm change will remedy that. The direct out of the preamp also makes my noise floor drop even more.

Also, here are the amp settings of the A370 that gets me +- 5dB from 20 Hz - 100 Hz in my room (updated 4/26/2018):

fMod 80 Hz HP filters in place:

TLC-1:

danvprod · « **Reply #10 on:** 29 Jul 2017, 07:11 pm »

Made some updates to reflect what has happened in the last couple weeks to the system. I picked up a P.I. Audio Group miniBUSS, which I am super excited about.

Also received replacement diaphragms from Loudspeakers Plus, which fixed the issues in the FR between the left and right speakers at 1.8 kHz.

danvprod · « **Reply #11 on:** 26 Apr 2018, 01:23 am »

Current setup as of 4/25/2018. High points:

* New rack -- Solid maple with 3" thick isolated top. New Turntable (Rega RP3). AR and Sony turntables have been sold. Suspended tables not a great match to my room. Elys2 cartridge. Sutherland Ph3D phono preamp.
* Soliloquy 5.2 speakers are going elsewhere in the living room system once I build some XOs for them.
* Experimented with toe-in and positioning. Ended up with outside corners 20.5" from sidewalls and rear outside corner 35" from rear wall. 0 degree toe-in.
* Removed all the diffusion from the room; no more RPGs.

Current measurement of subwoofers. L, R and L+R. +- 5 dB from 21 Hz or so to 110 Hz. (No smoothing applied).

.

Still working through some center image stability issues, but the changes in position have help, especially removing the toe-in and spreading out the speakers a bit more. Measurement of just the L and R co-ax from 200 Hz - 4000 Hz at listening positoning 1/6 octave smoothing.

Still want/need to get another bass trap to position directly behind my listening chair. Contemplating picking up a pair of freestanding bass traps with scatter plates (GIK) to place between the speakers directly behind my rack.

poseidonsvoice · « **Reply #12 on:** 26 Apr 2018, 01:42 am »

I would see if you can borrow some GIK 244’s on the side walls for the 1st reflections as an experiment.

It might work better than the hybrid diffsorber RPG panel.

The desk with chair and peripherals on the right wall may be a source of reflections.

Between the speakers, the GIK Alpha Panels may work well (again, 4 inch thickness).

Don’t neglect the wall behind the MLP. It can be a major source of reflections and can cause FR anomalies throughout the whole spectrum.

Remember your room dimensions are slightly on the smaller side and more square, as such room modes may bunch up more at certain frequencies. SBIR is obviously an issue as it is with nearly all speakers. I realize the speakers are OB, but diffusion treatments are not something I usually talk about in this sized room with the fixed distances that you have between the Super V and the front wall. Your ceiling and floor are the next closest reflection points after your sidewalls.

Throw up a measurement from 1khz to 10khz too if you don’t mind.

And I am really wondering now what your ETC curves between 0-40msec looks like for each speaker. And the decay times from 250 Hz to 4 khz. I am wondering if they are dramatically different from each other hence the image shifting.

Best,
Anand.

gregfisk · « **Reply #13 on:** 26 Apr 2018, 07:05 pm »

Hi Dan, Ask and you shall receive

. Also, I was talking about my response below this one being off topic.

Dan, Here's what I have found, first make sure you listen to Anand

. O.K. that's not what I was going to say but it's true

Here are a few things that really helped with my center stage. I brought my speakers at least 5' into the room, I realize this may not be possible. I added 6" GIK absorption panels at the first reflection points and installed floor to ceiling corner traps in the front corners. I have my audio rack on the side wall so nothing is in between the speakers. All of these things helped and I now have an amazing center stage. The instruments and voices float in the center of the speakers from the floor to about 7' high or more. My speakers are about 3' off of the side wall and about 5' or so off of the front wall. They are toed in so they are almost facing me. I sit about 10' away and the Super Vs are about 10' apart. You can see my room in my gallery. It is 20' x 30' x 10' so I don't know how any of this would work in your room but thought I would try and help.

Also, I have had my MHDT Havana in this system and really liked it. I also used my Joule Electra LA150MK11SE with my Super Vs and that was very nice as well. Now I have a Lampi Atlantic Plus with VC and currently I'm using a 1200AS2 amp that is kindly being loaned to me. Yes, the midrange does a great job of keeping up with the servo subs with this amp. The sound is fairly warm with the 1200as which surprised me. I've been looking at the Rouge Audio 1200AS2 based amp myself and If I get that sooner than later I would be happy to let you try it.

Greg

danvprod · « **Reply #14 on:** 26 Apr 2018, 07:06 pm »

These are individual chirps from the left and right speakers to the listening position (without the subs on), just to try and unpack some of the reflections and what I am hearing.

First I looked at the ETC curves of the L and R speakers. I notice at 12 and 13ms, there is two peaks on the left speaker that seem to stick out from the right. They certainly seem intense enough to be plausibly in the image shift zone at least for certain signals. So looking at some GIK 244s to place at the first reflection points and perhaps behind the rack between the speakers seems to be the next step.

Frequency response from 1kHz - 10 kHz also attached. Seems pretty reasonable and matched there too.

BTW, I did order a small desktop SS amp to try out, just to help rule out anything that might be going on in my tube amp. I’ll end up using it to power a small pair of speakers in my office at work, so its money well spent.

Because I am having a hard time describing what I am hearing in my sound stage I tried to draw an image of how I often hear singers in tracks. The start of the phrase being sung is nicely in the middle and has some width to it but into the decay of that phrase the images widens and pulls to the left (i.e. into the reverberant tail). And because its not equally balanced between L and R (i.e. it isn't just a blurring or widening of the image) it feels as though the image is not stable to my ears. Not sure if this makes any more sense, but this picture might..

Here is the FR measurements.

gregfisk · « **Reply #15 on:** 26 Apr 2018, 09:42 pm »

Dan,

Do you think the shift has to do with what the freq. is of the voice at the time it shifts?

In other words is the sound shifting only at a certain freq. like one speaker is louder at that freq. than the other?

I hope that makes since, it is the only thing I can think of that could be happening.

Additional thought: I just looked at your servo amp settings and one of the freq. nobs is set all the way to the left and the other all the way to the right. Not sure if what you hearing has anything to do with that or not?

Greg

Shakeydeal · « **Reply #16 on:** 26 Apr 2018, 10:27 pm »

Quote from: gregfisk on 26 Apr 2018, 09:42 pm

Dan,

Do you think the shift has to do with what the freq. is of the voice at the time it shifts?

In other words is the sound shifting only at a certain freq. like one speaker is louder at that freq. than the other?

I hope that makes since, it is the only thing I can think of that could be happening.

Additional thought: I just looked at your servo amp settings and one of the freq. nobs is set all the way to the left and the other all the way to the right. Not sure if what you hearing has anything to do with that or not?

Greg

Good catch. There is no way the phase and xover points should not be the same for both speakers.

Shakey

danvprod · « **Reply #17 on:** 26 Apr 2018, 10:33 pm »

@Shakey, @Greg --

XO and phase and level were set based on measurements to try and get the flattest bass response in-room taking into account modal behavior.

I worked with @poseidonsvoice extensively on this. Updated A370 amp settings above an also here (4/26/2018):

If you look at my subwoofer plot, you can see that there are attemps made to get the aggregate response of the subwoofers as flat as possible. That was only possible in my room by adjust the delay/phase crossover and level controls and ended up with asymmetrical XO slopes electrically to try and match the acoustic response in-room and have proper slopes acoustically. You can also see that they is a big modal dip on the left channel and a peak on the right channel, the resulting trace is pretty flat from just two subwoofers, and ones that are tied to the position of the overall speakers. Perfect world, I'd have four of these in a "swarm" to try and flatten the bass response even more.

Jonathon Janusz · « **Reply #18 on:** 27 Apr 2018, 12:31 am »

Dan, I'm wondering if Shakey and Greg are on to something. Based on your last post, I know that the settings you've come up with for the subs is getting the in-room response where you want it to be, but maybe that is primarily in reference to bass or sub-bass frequencies? In this speaker design, if I remember correctly, the subs on each speaker are tasked with playing up into the lower midrange (I think?). Would some of your work to get down low the way you want it be causing an issue at the top end of the frequency range the subs are playing at? The problem area you describe reads to me like it sits just before the subs hand off to the coaxials, meaning whatever you are hearing in this range is primarily coming from the subs.

I know it is probably asking a lot, but for sake of curiosity, you don't happen to have any measurements from before you worked with Anand to tune the system to where you are at now? Did you see the same hiccups with the subs set more like Shakey and Greg are thinking is the way to go? If not, maybe the real solution is to go in on the two more subs you were mentioning above specifically to take care of the bass issues the subs attached to the coaxes can't be tasked with taking care of, because they are really part of the mains? Either that, or again if I'm on the right track, maybe your plan "A" going up/over to one of the -otica designs with the separate subs would be a step in the right direction, as those designs (again if I remember correctly) play the main speakers down lower than the super-v coax, getting the subs out of the problem range and really dedicated in task to sub duty.

danvprod · « **Reply #19 on:** 27 Apr 2018, 12:55 am »

Well d*mn it if that didn't do it. @Jonathon Janusz, @Shakeydeal @gregfisk. Unbelievably frustrating. Set the A370s to what Danny had at RMAF and image is centered. Bass is less smooth for sure. Listening to Veedon Fleece right now and Van is floating in the center between my speakers.

Not sure where that leaves me? Either way is going to be a compromise.