Guys I need help. I just finished a pair of beautiful pensils for my 7.3's and as soon as I hooked them up there was massive distortion. I tried them on another amp as well and the same thing happens. Distortion on low volumes, it's crackly and fuzzy and just down right horrible. I haven't touched the drivers, I haven't even broken them in.
I thought that maybe some of the polyfil may be touching the back of the cone so I took off the back and removed the fill. Same thing. I thought maybe it was my amp. So I hooked it up to another amp and same thing. What do I do? Could it be that both of my amps aren't able to support a 6 ohm load? That doesn't seem possible as they're both perfectly happy with both 4 and 8 ohm speakers. I'm at a loss. I was hoping to start break in tonight but am riddled by the overwhelming distortion when I play the speakers.
Please help!
I thought that maybe some of the polyfil may be touching the back of the cone so I took off the back and removed the fill. Same thing. I thought maybe it was my amp. So I hooked it up to another amp and same thing. What do I do? Could it be that both of my amps aren't able to support a 6 ohm load? That doesn't seem possible as they're both perfectly happy with both 4 and 8 ohm speakers. I'm at a loss. I was hoping to start break in tonight but am riddled by the overwhelming distortion when I play the speakers.
Please help!
Doesn't sound like amps to me.
When you cut / routed the holes for the drivers, were all the surfaces flat? Could it possibly be that the frame(s) was warped a bit when the drivers were mounted? Did you try loosening the screws a bit to see of the distortion continued?
I wonder if removing the drivers from the boxes and just running them with a low-power signal will produce distortion...
When you cut / routed the holes for the drivers, were all the surfaces flat? Could it possibly be that the frame(s) was warped a bit when the drivers were mounted? Did you try loosening the screws a bit to see of the distortion continued?
I wonder if removing the drivers from the boxes and just running them with a low-power signal will produce distortion...
All the solder joints were solid. I didn't use the outer ring that comes with the drivers. The drivers fit perfectly if not a tiny bit snug. The cutout has a 1/8" round over on the inside edges. I really don't understand what could be happening. Tomorrow when I have more time I'll take one of the drivers out and inspect it for damages and try hooking it up without an enclosure to see if that helps to minimize or eliminate the distortion. I'll re-solder all the joints and try to sand off a little on the cutout to make it loose. Any other ideas?
Hi Steven,
As per members Buzzbob and Silver's advice:
Carefully check the drivers are mounted flat and you've not over-tightend the mounting screws. If the driver's power-trains are pulled out of alignment, you're hearing is coil rub. Running the drivers in this state will cause coil circuit failure in a matter of minutes. The drivers will be ruined.
Take the drivers out of the cabinets. Run them in free air on low volumes to check their operation. Then check your cabinet driver mounts. They must be flat.
When you re-install, take care not to over-tighten the screws. Use the edge of a straight steel ruler (or similar) to eye-ball the front of the driver frame as you gently tighten the screws. Make sure the frames remain flat.
If possible, post some high quality pics of the driver mounts in your cabinets.
If you still have distortion, then the problem is elsewhere, possibly on the source side.
Thanks
Mark.
As per members Buzzbob and Silver's advice:
Carefully check the drivers are mounted flat and you've not over-tightend the mounting screws. If the driver's power-trains are pulled out of alignment, you're hearing is coil rub. Running the drivers in this state will cause coil circuit failure in a matter of minutes. The drivers will be ruined.
Take the drivers out of the cabinets. Run them in free air on low volumes to check their operation. Then check your cabinet driver mounts. They must be flat.
When you re-install, take care not to over-tighten the screws. Use the edge of a straight steel ruler (or similar) to eye-ball the front of the driver frame as you gently tighten the screws. Make sure the frames remain flat.
If possible, post some high quality pics of the driver mounts in your cabinets.
If you still have distortion, then the problem is elsewhere, possibly on the source side.
Thanks
Mark.
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Well the distortion wasn't from the source as I was just playing another set of speakers with it immediately before I hooked up the 7.3's. I will still remove the drivers and sand a little off the inside edge of the cutout to let it be loose instead of snug. I believe the whole problem was from over tightened screws as when I released all the pressure all distortion ceased. Everything is great now. You guys are the best.
Hi Steve,
Some pointers:
Try to use the the extra connector sets that I supply with the drivers. At times like this, they make life much easier when checking or swopping out drivers. Soldering directly to the driver's main connector is OK but re-soldering must be done with clean joints and minimal heat, so as not to distort the main connector bodies (see pic).
Making a "snug" recess cabinet fit is OK but will require extra care to make sure the drivers are tighten down flat. The use of a straight/true edge of a steel ruler to "eyeball" the front of frame is a necessity with these types of installation.
If the drivers emit distortion in free air, check them on a friend's system. This helps eliminate other potential sources.
We fully sweep test all drivers before we pack them, so unlikely to be a driver build problem. There's something amiss with their mounting into the cabs, or its a source problem of some sort.
Note to all guys:
Take extra care when installing pressed steel, light-weight cast and polycarbonate framed drivers. These drivers are designed to be fitted onto flat surfaces, or non-compressed recessed mountings.
1 - Make sure the mounting surface and/or recess is flat and true (round). For recessed fitting, they should be just a tiny little tight at most. Best if the recess is slightly over-size (around 1-mm is good). For example, the O/D (outside diameter) of an Alpair 6 frame = 114-mm. The O/D frame mould tolerance = +/-0.18-mm. So making a recess diameter of 114.5 to 115-mm is the safer way to go.
2 - Don't over-tighten the mounting screws. On Markaudio drivers, the frame fronts are nice and wide, easy to eye-ball check the flatness using the edge of a steel ruler (or similar).
Cheers
Mark.
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I had a similar issue w/ an miniFonken Fostex 126 design. While they didn't sound distorted after mounting, there was certainly no "magic" that I've become used to with that driver even though they were broken-in for over 150hrs before hand.
I read the forums regarding overtightening and when I looked closer at the driver, it indeed was bent. I loosened the screws so that the frame "unbent" and the sonic improvement was not subtle....I'm now checking all my mounts especially on cabinets that have the driver brace.
I read the forums regarding overtightening and when I looked closer at the driver, it indeed was bent. I loosened the screws so that the frame "unbent" and the sonic improvement was not subtle....I'm now checking all my mounts especially on cabinets that have the driver brace.
Hi Guys,
The most vulnerable frames are the pressed steel variety, particularly those of reverse press design (see pic). Take extra care with any pressed steel frame. Once they're deformed, its pretty difficult (na impossible) to get them back to 100% true alignment.
Cheers
Mark.
The most vulnerable frames are the pressed steel variety, particularly those of reverse press design (see pic). Take extra care with any pressed steel frame. Once they're deformed, its pretty difficult (na impossible) to get them back to 100% true alignment.
Cheers
Mark.
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Mark, I just wanted to take the time to thank you for an amazing product. I've now broken the drivers in for a total of about 50 hours per your instructions. I'm beyond amazed at how great these drivers sound. Simply stunning tonal accuracy, imaging, and everything else. I just can't believe that these sound this great. Thank you!
Just for reference. The 7.3's are being provided power by a Class D Audio SDS-224 amp and an Audio-GD NFB12 Dac/Preamp combo. Simply perfect combination. The speakers will draw you in with their lush detail and make you late for work. I love it! Also, for those who want to know what my newest speaker build with the 7.3's look like, here's a website where you can view my builds. There's also an album on there for my amp build as well as other various builds. Http://Szaiontz.imgur.com
Just for reference. The 7.3's are being provided power by a Class D Audio SDS-224 amp and an Audio-GD NFB12 Dac/Preamp combo. Simply perfect combination. The speakers will draw you in with their lush detail and make you late for work. I love it! Also, for those who want to know what my newest speaker build with the 7.3's look like, here's a website where you can view my builds. There's also an album on there for my amp build as well as other various builds. Http://Szaiontz.imgur.com
Buzz, in all honesty, I think the 7.3 trumps the 10.2 with ease in regards to tonal accuracy and 3D sound stage. But to be fair, I never got to listen to the 10.2's with my new equipment. My Father is now the owner of them so maybe one day I'll bring my gear over to his house and give them another shot. Truth be told, I had never intended on buying the 7.3's. They were in fact a somewhat surprise payment for building some enclosures for a friend of mine (see the stainless steel enclosures on my build log website). I'm sure glad he bought them for me as I'm now regarding them as the best speaker I've ever heard. Could it be the synergy of components + speaker? Sure. Is it? I don't know, but I do know that it sounds amazing.
I've heard Magnepan, Quad, Martin Logan, Usher's TOTL floor stander, Klipsch, Canton, Focal, KLH, Harbeth, Lowther, and many more top of the line speakers from each manufacturers and I'd rank them up with the best any day of the week. Sure they may not be ground pounders or block rockers but they definitely don't lack where it counts.
As for the B1 and F2, I recently gave those to a friend of mine who is interested in audio as well as DIY. He and I will knock them out in a couple weeks as he gathers more information to populate the boards. I figured since you passed along a good deed, I would too.
I've heard Magnepan, Quad, Martin Logan, Usher's TOTL floor stander, Klipsch, Canton, Focal, KLH, Harbeth, Lowther, and many more top of the line speakers from each manufacturers and I'd rank them up with the best any day of the week. Sure they may not be ground pounders or block rockers but they definitely don't lack where it counts.
As for the B1 and F2, I recently gave those to a friend of mine who is interested in audio as well as DIY. He and I will knock them out in a couple weeks as he gathers more information to populate the boards. I figured since you passed along a good deed, I would too.
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Oh, okay. Well in the pensil cabs, keep in mind it hasn't fully broken in yet, but it's lush. Extended top end, natural mid range, and a plentiful bass response. I don't feel it's lacking a single thing, to be honest. I have a relatively small listening room of 10' x 10' so they seem to compliment perfectly with my space. When I have more time I'll move them out into my much larger living room and give'em a whirl. But for now, regarding the pensil cabinets and referencing my recollection of sealed enclosure tests with MA drivers, I think P10 and Scott nailed it with the Pensil 7.3.
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