Bash 300 Help!

What receiver do you have? Do you have another driver you can plug in temporarily to see if its a driver issue?

Check for the obvious - crossed wires?

Make sure your not using a RCA cable made for video it has a 75 ohm impedance, that will cause the problem your having. Try an RCA cable that you know to be made for audio.

Later
Dan

BINGO

IIRC, RG59U is 75 ohm cable, try it with a regular audio cable



Later
Dan

What impedence should one be looking for? I notice all of monoprice's subwoofer cables are listed as 75 ohm - a mistake on their part?

Which input are you using on the BASH?

The mistake would be calling it an audio cable, as you've just found out it kills the signal. RG59U is for video, swap out the cable and see what I mean.

Later
Dan

RG-59 is fine for audio. The impedance/resistance of the wire is negligible, it's the connectors that really determine the impedance. 75 ohm is the accepted standard for home audio and video connector impedance. If anything, video rated cable is better than "audio only" cables...video requires more bandwidth. Analog audio, including subwoofer outputs, is less demanding of cables than video or digital audio.

Instead of telling us you're getting no output. Have you got an SPL meter? Play some test tones and record the frequency and measured SPL and distance measured at. What about cone excursion? Is the cone moving? Maybe you're getting all of the ouput that $25 woofer is capable of in a small sealed box. How is your system calibrated. We don't have enough objective evidence to know whether or not you actually have a problem.

Have you got a friend with a surround receiver? Assuming you're objectively getting less output than expected (see above) then I'd try the amp on a different model/brand receiver. This will confirm if there's a problem with your BASH amp itself. If it works fine on someone else's receiver, then it would appear your Kenwood doesn't have enough output voltage to drive the BASH properly...unlikely.

-Brent

swapping the RCA ends, most likely will NOT fix it

Glad to know i'm not on crack
Dan

If swapping out the cable made the problem go away, then it was a bad cable. 50->75ohm isn't going to destroy your 20hz frequencies. Maybe you could measure the impact by the time you get up to 2,000,000hz...

(Don't ask me about all the times I've done much more vicious things to cables other than mismatching impedances... heh heh...)

Besides, 75ohm is actually what is spec'd for digital signals, so technically it could be an 'audio' cable anyway.

delsol,
did you buy the single 4 ohm EQHS 12"? can you post the specs for that driver?
The specs on the ED web page are for the single 2 ohm coil.


Later
Dan

wildfire99,
since your basically making my point, i'll explain why I thought he needed another cable.

After re-arranging my system I accidentaly hooked up a known to be good subwoofer with a spare "high end" cable, and I was shocked at how crappy it sounded. As it turns out it was a silver plated sissy cable for my DAC, hence the 75 ohm impedance and it sounded like $hit as a subwoofer cable.

I made the same mistake, that's how I know.



Later
Dan

OK. I run RG-6U cable capped off with 75ohm connectors all day long for subs and it "sounds" great, plus it's a lot easier to get than whatever magical cable/connector is the current 'fad' style (gold, braided, non-braided, twisted, silver, supercooled, golden ratio, special dielectric, special jacket, crystal tuned, non-oxygen, etc etc etc).

Thus I was just saying, that running a 75o cable isn't going to magically turn your sub into mush. If it did, then we'd have a lot of angry people all over the place who have "bad" cable hooking up all sorts of audio gear. I can't recall any demonstration that swapping 75o for 50o would make an audible difference, but swapping a 75o cable with a cracked solder joint for a 50o one with a solid connection will definately be obvious.

Even a high end silver-plated solid-gold conductor 50ohm subwoofer cable is going to sound like trash if the connector end is falling off (probably because the solder didn't stick well to the silver plate).

I'd be more worried about distortion caused by cheap amplifiers for a subwoofer application, before taking a magnifying glass to my interconnect terminations. We're talking about audio frequencies here, and the human ear is about the least precise instrument you've got. Now if you want to run microwave frequencies over a 100m run... now you've got my attention over cable impedances.

I don't care if people want to run out and buy hand-crafted unobtanium cables, but I just wouldn't want new people thinking that if their sub sounds wonky it's because they used RCA connects instead of BNC or that their cable must be silver plated or blessed by an audio priest or anything; audio is a non-demanding application. Don't forget, you're dealing with a +/- 20% tolerance also. Your perfect 50ohm cable may be 60ohm and still in spec (or 40ohm!)

For the record, all my Monoprice interconnects ("improperly" terminated at 75ohm and running RG-59U) sound great.

Now you've got me thinking, hmmmm?
I never thought of a "regular" audio cable as anything other than a direct connection of minimal impedance. I know the 75 ohm stuff its tailored to form impedance matched transmission lines of exceptional bandwidth, well beyond whats needed for the audible range of audio signals. I'm gonna try to make some time to measure some different types of cables to see if I can measure a difference in how they handle the signal. I'm curious to see if there are measurable impedance and phase shifts that would make the cables audibly identifiable. I always associated the "bad sound" with the materials and construction, a woven shield against a foil shield, and a single center conductor of a steel like alloy that's copper plated, all this effort to make a high impedance interconnect that's tailored to carry signals that are extending into the RF range. I dunno, but I am definitely curious now, that sucks, thanks for the brain teaser dude.



Later
Dan

That would be awesome if you could take the time to do such a measurement and comparison, especially if you took all manner of cables (from Monster to Monoprice, and from Copper to Gold and Silver and maybe even coat hangar wire in-between), as well as known good cable with various connector types since special cable is often marketed with special connectors.

I'm not enough of an EE to comment knowledgeably about it beyond having seen such comparisons on the web that show measurable differences but only once you get past 20khz.

There aren't enough good tests done with audio and interconnects using real equipment (like an oscilloscope) to show just what an extra $500 buys you over a $5 audio cable. Those few comparisons I have seen tend to show that expensive cables that 'sound better' are actually rolling off as early as 15khz! I guess that's smooth? I wonder how many people use cable like that with one of those 40khz supertweeters, and marvel at the sound?

Audioholics has a brief discourse on video cables as transmission lines that is relevant and may be a starting point, though they don't discuss audio, only higher frequency video.

delsol:
********

You just plain got a "bad cable" from Monoprice.
If you have not already, call them and they will replace it "free".

If anything, RG-59U/75-ohm cable used for a subwoofer cable, like Monoprice uses, would be better as it's shielded making it less prone to picking up noise.

I & many many others have used the stuff for just about everything from typical analog video & audio, to all types of good ol rca-ended digital feeds.

Nothing magical going on here, delsol simply got a bad cable.!

Glad your sub works now, but call Mono so they can ship you a replacement "free".

Hey Dan:
***********
Test away, it's been done many times by others who possibly thought one thing or one way, only to find out another in the end. Best of luck as others here may likey find your testing results rather surprising..
You do know that the ~{Plutonium center-line sprinkled cables with crushed diamond infused locking ends}~ are currently the best available, right...!

Cheers
---------
Geoff

delsol,
wow. Bummer I'd have liked to modeled it in the puter.

Aside from being more than mildly inaccurate, that's the "lazy boy" answer. They should include or offer actual params on request for any driver no matter how much or little it costs.


Later
Dan

Geoff,
You could be 100% correct on this and I agree. he should get a replacement and hook it up to see. I'll be making an effort to educate myself a bit better about interconnects in the near future. I didn't mean to suggest that "boutique" cables were better, I'm a plain vanilla/ copper guy myself.



Later
Dan

Yup, me too for the most part. I've built a number of my cables also. Latest being a set of R-L channel twisted pair Bi-Amp speaker cables.

Very "affordable" cables, (interconnects or speaker), that some might call "boutique" cables are one thing. But outragious prices for cables like Monster pushes, is just plain insane. Their marketing, like Bose, has so many BS'ed it's unbelivable...

Later
--------
Geoff

Just to chime in here and I figure this probably has been dealt with and I am just sharing my experience. I just got my BASH 300S this weekend and it's running on some home made subwoofer cable made with 75 Ohm cable and RCA ends and it works great even made another that I use for a fairly long run to another smaller sub that I made and it works without a problem. Just my 2 cents and I hope you resolve your problem.