wrench_peddler Posted February 14, 2004 Share Posted February 14, 2004 I hooked up my new 1000 watt Samson to my 12" dual 8ohm JL audio dual bandpass box tuned to 35hz and the sub is almost non-existant until I have the old Scott tube amp cranked to 50%. It's the same story with the SS Onkyo system. The old Onkyo amp I had hooked to the sub was louder and it is only rated 100 watts per channel in stereo. I know the Samson is only rated about 375 watts per channel into 8 ohms but I am very disappointed. Quote Link to comment Share on other sites More sharing options...
Deang Posted February 14, 2004 Share Posted February 14, 2004 Something is "wrong" here. Are you using the correct channel on the Samson for use with one sub. If not using both channels, I think you have to be plugged into channel '1'. Check your manual. I imagine you have the gain control turned up to match to your mains? Quote Link to comment Share on other sites More sharing options...
wrench_peddler Posted February 14, 2004 Author Share Posted February 14, 2004 I have tried it every way the book shows. Stereo, bridged, and parallel, I even hooked both coils of the sub to the bridged connection giving the amp a 4ohm load and it is still anemic. The gain on the Samson is all the way up. The sub sounds great, tight, clean, crisp, once you get the volume up so loud on the Lascala's your ears begin to bleed. I can turn the bass way up on the Scott and it can be heard at lower volume but I would like to keep the Scott flat if possible. The only thing I can think of is that the Lascala's are so efficient and the sub so inefficient that the two are unable to meet in the middle. The sub is louder when driven with the center channel output from the Scott than it is driven by the sub preout from the Onkyo reciever. With the Scott at 5 on the volume, the sub did actually bottom out a couple of times on an extremly heavy bass cd of my sons. I could be simply expecting the bass to be as loud as it was with the other Onkyo driving it with the bass control set to max and the treble all the way down. I have two Onkyo recievers, one for the HT and the other was used for the sub until I got the Samson. Everything may be right and I was just expecting to be blown away. ???? Quote Link to comment Share on other sites More sharing options...
michael hurd Posted February 15, 2004 Share Posted February 15, 2004 Something is definately amiss here. What I believe the problem is that you can't generate enough voltage to drive the preamp stage in the amplifier, even with the gains fully up. This happens when you use some pro audio amplifers as they require more voltage to reach full output. I believe that you need one of these balance buddies from Rane. You can find them just about any pro audio shop. www.bhphotovideo.com has these items, and you can google more shops closer to you. General Description The Rane BB 22 Balance Buddy is a handy professional-grade tool used to provide isolation for and convert unbalanced -10 dBV ( 316 mv ) consumer level RCA outputs up to balanced +4 dBu ( 1.23v )professional XLR inputs. The BB 22 converts one pair from -10 dBV to +4 dBu. There are two male XLR connectors and two RCA jacks. Unbalanced lines should always be kept to 10 feet or less to prevent undesireable effects such as hum and noise. The BB 22 allows conversion to balanced lines that can be run across a studio or a house without loss of signal quality. For instance, a BB 22 may be mounted to the back of a jukebox converting its unbalanced outputs to balanced lines, feeding an amplifier in another room. Signal-to-noise performance is perfectly preserved using the BB 22, since it uses only passive transformers to convert signal levels. It adds no additional noise whatsoever. Use of professional quality nickel core ('80' Ni) transformers guarantee low distortion, wide bandwidth and high signal level handling capability. The BB 22's isolation transformers provide a quick and affordable answer to most jobs requiring signal level conversion and output balancing. As you can see, it is a step up transformer that will boost the output of consumer equipment ( 316 mv rms ) up to ( 1.23 v rms ). You will also need two XLR cables from this unit to the Samson. The only info I found on the s700 and s1000 is that you need at least 0dbu ( 775mv ) to get full output from the unit. And that's WITH the gain knobs in the full clockwise position! The gain knobs can be turned down more with more input voltage. Quote Link to comment Share on other sites More sharing options...
formica Posted February 15, 2004 Share Posted February 15, 2004 ---------------- On 2/15/2004 1:12:17 AM michael hurd wrote: What I believe the problem is that you can't generate enough voltage to drive the preamp stage in the amplifier, even with the gains fully up. This happens when you use some pro audio amplifers as they require more voltage to reach full output. ---------------- Michael thinking the same thing i am... You should be able to bring the amp to clipping if the voltage is high enough... which would represent it's "full" output. Quote Link to comment Share on other sites More sharing options...
wrench_peddler Posted February 15, 2004 Author Share Posted February 15, 2004 I've done a little reading and I believe you guys are right on the money. I have a bid on a BB44 on ebay and have my eye on a couple new ones if that doesn't pan out. Thanks. Quote Link to comment Share on other sites More sharing options...
michael hurd Posted February 15, 2004 Share Posted February 15, 2004 No problem! After all, were all here to learn a little! My head hurts trying to do some of the math, but you couldn't have possibly even got to half the rated output (187 watts) with a continuous test tone and the receiver output maxed out, and the gains on the samson full up. My guess is that the amp was producing maybe 50 watts at best. 64 watts corresponds to a gain of 15 db over the 1 watt sensitivity of the subwoofer. I do not know what it's efficency is, but if we assumed 88 db, then adding 88 and 15 we get 103 db. I don't know what you have for main speakers, but if you have lascala's or k-horns then they would equal that output with one watt. Quote Link to comment Share on other sites More sharing options...
michael hurd Posted March 9, 2004 Share Posted March 9, 2004 Wrench_peddler, did you get things straightened out yet? Does the samson work properly now? Quote Link to comment Share on other sites More sharing options...
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