2. speakers
  3. 150303-1627

Swapped long wall to short wall and now I am having some big issues

I have a 14.5 x 27 ft x 8' room (it is narrower at 12 ft (the last 6 ft on the end where I have the speakers)


I had my system aligned on the long wall with the rack in between the speakers.

The speakers were 9' offset from listening position and the side wall were so far away (and had two record cabinets) that they were out of the equation.  I had real traps mondo bass traps in the corners and GIK art panels to handle slap echo.

The sound was excellent - great tonality, dynamics, imaging. The only issues I had were a limited listening area and not back enough for full speaker driver integration.


After listening to a friends system in a 12x23 room - old home with wood construction I was a gasp. His system was short wall and there was great integration with easily 2 rows of 3 people could sit and listen. It was a very relaxing and engaging experience.


Fast forward. I made the move. knocked out a closet in the corner. Removed one of 2 floor to ceiling record racks, a Wurlitzer jukebox, and Victrola.  I placed the equipment racks on the opposite side wall.  The speakers were set up 2 feet from the walls in front of the two corner bass traps. The sound was dreadful.  The once luscious mids were thin and highs (1.2-3khz) were bright and cymbals were brittle, hard strumming acoustic guitars and brass sounded terrible as well.  If the music got dynamic - it sounded terrible.


The vinyl was bad - cd atrocious.


I went ahead and took all the acoustic panels out except the GIK art panels.


I did some research and bought some GIK Impression 2' 2" panels for first reflection  and GIK Impression 1' 4" diffuser/bass panels for the front corners allowing absorption from the back.  This was much better but still way off.  I moved the speakers out from the wall and then the instrument subtle details snapped into place - at 6 ft this was most apparent however it developed a very bloated mid bass.


I am looking for ways to tame the high end and mid bass but bring out the mid range,  I do not want to over treat.

This in incredibly frustrating as I had my sound very refined and the short wall setup should theoretically produced better results.  I would be interested in your comments and suggestions.


Thank You

128x128audiotomb

Showing 6 responses by almarg

almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 

... by your description it seems that the speakers are already "bright’ in the near field.


No, I didn’t intend to indicate that. I think of the brightness region as being in the area of roughly 4 to 8 kHz or thereabouts. According to my measurements that region is if anything very slightly under-emphasized relative to most of the rest of the spectrum. In the 3 to 4 kHz area, though, there is a narrow peak, although that peak is not quite as high as the one I referred to at about 18 kHz.

BTW, I should add to what I said previously that the measurement microphone was omnidirectional. So the fact that it was positioned directly in front of the tweeters at a close distance (30 and 36 inches for the measurements I did) would not have under-emphasized what it was picking up from the woofers or the midrange drivers, even though those drivers (especially the woofers) were somewhat off axis. Specifically, the mic was an Earthworks M23. And to assure accurate results DEQX supplied a calibration file for the specific serial number of the specific mic,the file having been supplied to them by Earthworks and converted by them to the format that is necessary for use with the DEQX software.

In any event, as Tom indicated Daedalus speakers are known for their accurate tonality and non-fatiguing sonic character. "Natural sounding" would be another way to put it, IMO. They are not excessively bright by any means.

Best regards,
-- Al


almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 

the switchbox has no resistors

those amps are not sensitive to no load condition

Wow, that was quick!

Given that the amps have output transformers I’m not sure how or why they would not be sensitive to the no load condition (when processing a signal), but I’m sure Richard wouldn’t have said that without good reason.

In any event, since both amp/preamp combinations manifest essentially the same sonic issues in the new arrangement it appears that we can rule them out as suspects.

Best regards,
-- Al


almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
I could ask Richard on the switch box

Alternatively, if you have a multimeter, with the switchbox disconnected from the speakers and the amps you could measure the resistance between each + input terminal of the switchbox and the corresponding - input terminal, while the input being measured is deselected by the switch. If the measurements are infinite or very high, say several dozen ohms or higher, regardless of whether there is any relation to the sonic problems I would henceforth avoid having the deselected amps powered up while a signal is being applied to them.

Best regards,
-- Al

almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
Thanks for the additional info, Tom & Alan.

Tom, I see that you have two preamps and two pairs of tube-based monoblock amps in the system, with a custom made high quality switchbox to select which amp outputs are used to drive the speakers. Two questions:

1) Have you tried both sets of preamps and amps with the new positioning, and if so do the problems manifest themselves with both?

2) Does the switchbox apply load resistors to the outputs of the amps that are not selected?

If not, by any chance have you ever had the unselected amps powered up while a signal has been applied to them, especially in the recent past? As you most likely realize, given that these amps have output transformers doing so would be a no no if load resistors are not applied to the unselected amps by the switchbox, as it could conceivably cause damage to their output transformers and/or output tubes as a result of what is called "inductive kickback."

One thing that prompts this question is the reference in the listing of the switchbox in your system description thread to switching "on the fly."

Best regards,
-- Al

almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
... that speaker which has one design flaw, it has two tweeters which are too far apart to reproduce the highest frequencies in balance with the rest of the speaker.
Mijostyn, as I mentioned in my previous post I have the same speakers as the OP. I also have a DEQX HDP-5 in my system. When I acquired the DEQX about three years ago, as part of the calibration and correction processes it performs I used it to measure the frequency response of the speakers, with room reflections minimized. I accomplished that by moving each speaker to the center of the room, placing large sound absorbent panels along the nearest walls, and a pillow on the floor directly in front of the speaker being measured. The measurement microphone was placed on a stand, directly in front of and pointed at the tweeters, at distances of 30 and 36 inches (those distances having been chosen per DEQX recommendations, to minimize room reflections that are picked up by the mic, and to delay them as much as possible relative to the sound reaching the mic directly). The HDP-5 puts a lengthy series of brief frequency sweeps through the system, and computes the frequency response and other speaker characteristics by analyzing what the mic picks up.

Those measurements revealed that the greatest response in any part of the audible spectrum occurred at about 18 kHz, and the average response in the top octave (10 to 20 kHz) was slightly greater than the average in the rest of the spectrum.

Also, from a subjective standpoint, in addition to the characteristics the OP mentioned in his post just above Daedalus speakers are widely recognized as being "fast" and dynamic. That would seem to be consistent with my measurements.

Regards,
-- Al



almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
@audiotomb

Hi Tom,

Sorry to hear you are having this very frustrating experience. We have the same speakers (Daedalus Ulysses), as you may recall. My room is 13 x 22 x 8. I have the speakers set up on the short wall, about 4 feet out from the front wall (which is mostly a large picture window, with wood blinds in front of it), as measured to the front of the speakers. The speakers are about 7 feet apart, center-to-center. My listening distance is about 12 feet. The central third of the rear wall opens to another room, and the part of the side wall that is near the left channel speaker opens to another area. The walls are wood paneled.

I have no particular suggestions to offer at this point regarding speaker positioning or acoustic treatments. However the sonics you have described are so vastly different than anything I have ever heard from my Ulysses, as well as being vastly different from what you had with the previous setup, that I’m wondering if some misfortune unrelated to speaker positioning and room acoustics might have been inflicted on the system during the move. For example, perhaps a tube-based component was jarred and the performance of one of its tubes was affected by the physical shock. Perhaps something is amiss with a connection somewhere, perhaps internal to a component if not externally.

Those kinds of possibilities are about all I can think of at this point. As I said, it’s hard for me to envision Daedalus speakers sounding as you’ve described, with a seemingly reasonable setup in a reasonably sized room.

Best of luck as you proceed,
-- Al

More to discover