GoodSoundClub - Romy the Cat's Audio Site

In the Forum: Audio Discussions
In the Thread: A listening room for a domesticated Cat?

Post Subject: Virtual visit to Romy's setting up (part 2)Posted by scooter on: 8/19/2016

This week Romy was kind enough to invite me over for a few days for some Apprentice work and philosophizing. As I alluded above, my Apprenticeship contribution consisted principally of moving some audio gear, searching for some esoteric stuff hidden amongst thousands of moving boxes, holding a few tools, and connecting some non-critical cables.

Thursday was more execution. Basically, Romy strategically picked some music to listen to, thought a bit, then described a problem in detail, why it occurred, exactly where it occurred in the system, and appropriate correction. No fq or SPL measurements at all. I think that skill is the intersection of art and science and comes from a lot of thought and decades of testing / listening.

I'm sure Romy will disagree with most of this, but since I was the only one afforded the Apprenticeship opportunity, I feel an obligation to provide everyone a flavor for the set up process. Think of these few examples as a virtual visit to Romy's house which probably are closer to fiction than reality due to my very basic audio and electronics knowledge. In no particular order:

1. In the morning we disconnected the $30 DIY stepped attenuators and connected the preamp (which works better when warmed up). Consequently, proper impedance helped correct absence of lower end, collapsing sound fields, harshness, really screwy imaging...

2. As Romy mentioned above, the bass towers are still missing some new drivers resulting in an impedance mismatch in the bass channels; to solve this second issue, we dug up some industrial ceramic rheostats in his basement. One dialed in right at 8 ohms the other was wonky only got to 6. Maybe we set them both around 6. He said they would boost gain, increase softness and improve sonics. They did just that. Interestingly, those bass towers keep SPL high over distance and I think it is worth reading more about how that works. . .

3. We found the RAAL ribbons in a big green moving box and did a quick and dirty bolt on; we connected a few more horns. We used a tape measure for a quick distance measurement between the top edge of the upper bass horns and the center of Romy's chest in the listening chair. Then we eyeballed everything else for quick alignment. This all got thrown out of wack as we changed cables, replaced tubes, moved the chair around. During this time, Romy detailed a bunch of specific issues from higher fq waves bouncing around and said a little bit of temporary diffusion & absorption would help:

We hung that dainty clock above the left side windows. Romy said that it was a very good diffuser (even without those plastic leaves!?)

Fortunately, his wife did not see us put three large screws into the freshly painted wallboard below the clock and above the windows closest to the speaker column to hang a child-sized brown $3 blanket which partially draped over two of the windows

Romy put another $3 blanket on the wood floor (a few feet front and outside the right speaker towers)

Behind that blanket he leaned 2 of those white foamy absorption panels on his step ladder at roughly 110 degrees (the stepladder had a horizontal foot at the bottom so I think that angle was strategic simply to prevent the panels from falling down)

FYI room already had a bit of sound treatment but no furniture: large oriental rug partially covering hardwood floors, large record racks fairly populated on right side towards the back, cd racks on back side, lots of moving boxes, a listening chair, and a pleather office chair. The floor also was littered with a bunch of tools, cables, mysterious equipment, some trash, and a few tubes that Romy replaced

The windows, back wall and front wall need some treatment

4. Listened to some mono piano (I think partially for imaging troubleshooting)

5. We put those SRA tables under equipment, rewired some stuff, organized the cables with zip ties, checked driver phases with a specialized hand-held gizmo, and connected the power regenerator. Romy talks about the Pure Power on the electrics thread; it works as he described (and has a special screen off mode)

6. I also asked Romy why he didn't upgrade his time-alignment parabolas from two-dimensions to three-dimensions (e.g. not running horns parallel to the floor). He said basically that three-dimensional time alignment would require locking the listener's head with a vice in one precise position or ALL channels would be off; two-dimensional provides some reasonable margin of error

For your entertainment, during the day I thought the playback was improving but sometimes was a bit imprecise and boring, the lower registers of the piano sometimes came from a different room, some (but not all) larger percussion instruments suffered from fq that was obviously cut off, some lower strings / horns were grating, the harpsichord sounded like a child's instrument, etc. In some cases Romy just told me I was wrong (he was quite polite, in fact). In some cases he said that didn't matter and will be corrected in due time (e.g. by bass boxes coming in September, room treatment, time alignment, fine tuning, injection channels, etc.).

At the end of the day, we listened to music and despite all the outstanding set-up required, those were an enjoyable and sometimes spectacular couple of hours. Principally due to music selection. Sometimes those horns and bass towers got orchestral big. I also asked Romy how he felt about progress. He said he was quite happy as room is better than he expected and that virtually all problems will be solved by set-up and acoustic treatment. He thought the system was about 35%-40% of where it will be at say the end of the year. After final set up, he sees a reasonable probability (say around 40%) that bass and/or mid-bass will need to be revisited. This also might mean the listening position is closer to the front of the room? Interestingly, over the three days the listening chair creeped over 1.5m forward

There is a lot more to come. For example, Romy brainstormed some very special ideas for the front wall but I won't let the cat out of the bag...

In closing, I would like to thank Romy, his wife, and the Russian women for their superb hospitality. Really appreciated the opportunity

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