Bypass mode on 1068, bass overkill

[bleeding ears]

Hi guys, has anyone else found that bypass mode on the 1068 processor creates too much bass.

Ok, perhaps its not actually creating the bass but it does allow too much bass thru, a lot of the time.

I find the sound with some cd's to be substantially better in bypass compared to stereo mode, however with other cd's the bass is just unbelievably over the top in bypass mode and I have to go back to stereo to control it.

Eg Madonna's song "RAIN" from the " SOMETHING TO REMEMBER" disc.

At certain points in the song the bass is ground shaking, even more so than when my sub is on. Remember the sub does not operate in bypass mode.

Perhaps my large speakers (which I run in small setting) contribute or are responsible for the bass overkill?

Anyone else have similar sound happening in bypass mode or know whats happening?

Anyone know how to rectify this?

I like bass but this is too much.

Pete

[Stevebez]

Well bypass eliminates the sub feed and pumps everything to the fronts - all settings are bypassed - even the EQ switch to limit dynamic range is bypassed, and perhaps small settings too ?. Stereo mode has sub enabled - if anything the stereo mode should give more bass... but that may depends on your sub settings / cross overs.

Rgds Steve.

[Stevebez]

Oops!

[grit]

Ya know Pete, I've noticed that too, but I'm blaming another component in my setup: The Rotel RCD-1072. However, I have *not* tested this with any other pre/pro, so who knows. My basis in thinking so was that I do not recall my RCD-1060 in analog mode producing so much bass. And I get the same feeling you do... bass overkill. It seems to be overpowering the rest of the sound. The 1072 has always emphasized the bass a bit, but now it seems too much.

Now, in all fairness, here's why (I think). I recently upgraded from a 1075 amp running B&W 703's to a 1095 amp running Aerial 7b's. The Aerial's are a tougher load to run than B&W 803's, thus the extra power. But what *I* think is causing the difference is that the Aerial's have a rear port. The 703's & 803's have a front port. I can't move the BACK of the speaker more than about 12-15 inches from the back wall. I think that rear-firing port is contributing to my excessive bass. With the 703's, I always noticed bypass mode added more bass, but never too much. Perhaps now it's too much because the 7b's have a lower range than the 703's (the 7b's are comparable to the 803's).

However, when I switch to a non-bypass mode (either the RCD-1072 in stereo w/o a sub OR the RDV-1060 via digital cable), the bass is well-matched to the rest of the music. Of course, I lose the better imaging and clarity the 1072 provideds in bypass.

[bleeding ears]

Grit, my Energy speakers are rear and front ported, a bit unusual I guess.

Like you are finding, the combination of having a rear port and being a little close to the rear wall may be contributing to the excessive bass I get, but I doubt it would be all because of the port and placement.

My speakers are around 18 inches from the rear wall and my listening room is not ideal. It is all glass and floorboards with a large rug. The room is open and is quite large so a small room is probably not a contributing factor.

I will try moving the speakers out further and see what I get but I feel that this excessive bass is just too much to be fixed by speaker placement.

It would be interesting to hear from someone running bookshelf speakers to see if they get any excess bass in bypass mode.

As I stated earlier it is only with some songs, particularly where there is heavy bass such as synthesized bass. Eg Madonna's "RAIN"

I will get back on what speaker placement does to help.

Mean while is there anyone else with this excessive bass problem ?
Or is there anyone with bookshelf speakers using bypass mode on the 1068 processor.

[greenjudas]

Hey Bleeding a** whoops,I mean ears :B .The real problem you have as far as I can see is:what are you doing listening to Madonna :rofl:

[Nolan B]

as fare as I know this is caused by the LFE redirect. Unlike the 1068 my 1067 alows you to turn the LFE redirect on or off. I find when running bypass for DVD A or regular CDs having it on adds a lot more base. With some DVD As you need it while others need it turned off. I am surprised the 1068 doesnt have this option

[dknightd]

My guess is that it is room modes. When in bypass mode bass would go to the main speakers. When in stereo mode I assume the bass goes to a subwoofer.
My guess would be that the main speakers are exciting a room mode that the subwoofer is not. If so, positioning should help.

[Kevin D]

I am surprised the 1068 doesnt have this option

It's supposed to.. Where did you play with one that didn't?

Kevin D.

[bleeding ears]

Vancouver is the LFE redirect you mention the MAX, YES or NO settings under the advanced subwoofer menu on the 1068 ? because that is the only LFE settings I could find.

If this is the menu and settings option you are referring to I cannot see it making any difference because there is not any subwoofer output signal when using analog bypass on the 1068.

Therefore the bass must always be redirected to the mains I assume?

Does this sound correct?

If so, is there anything that can be done to help the bass overkill I get?

Perhaps a modification such as that done on the Rotel units with the double bass problem?

Anyone know? Keving D any ideas on this?

Thanks guys
PS Green Judas, I think your spelling mistakes may indicate what is subconsiously really on your mind. Oh and have you listened to your prince albums lately. LOL :rofl:

[Kevin D]

LFE redirect option is under the MULTI-INPUT setup. Turning this on copies everything 100hz and below from the main multi-ins and sends it out the sub output. This only applies to the multi-input bypass, not BYPASS mode on the regular analog inputs.

Kevin D.

[Nolan B]

It's supposed to.. Where did you play with one that didn't?

Kevin D.

sorry i could be wrong. i was under the impression that the 1068 did not have the same option as the 1067 to turn it on and off.

[Kevin D]

The 1066 and it's siblings did not have an option. You had to cut resistors on the multi-input board to turn it off. Turning it back on wasn't quite as easy.



Kevin D.

[grit]

Pete, what CD player are you using? I'd like to eliminate the 1072, if I can. I know in my case, moving the speakers might help some, but there's always been more bass from the 1072. I'll try goofing with the analog again on the 1060 and see where that leaves me.

[bleeding ears]

Grit, I have a Rotel rcd965bx which got great reviews in it's day, about 12 years ago, however I have actually been using my onkyo dvd player thru analog which sounds a touch better to me than the cd player.

The onkyo seems to have slightly tighter bass and a cleaner sound.

I will try my cd player again and have a listen and then I will try to reposition my speakers to see what happens. I will then report back, however I wont get the oppourtunity to do this for a day or two, so you will have to be patient.

I seiously doubt that the cd player or dvd players are to blame, however I will still try it out.

I am starting to think it is just the ability of our speakers to go down low and reproduce the bass they are given, whereas smaller speakers may not be able to go as low and hence do not reproduce the same bass.

My listening room is possibly also a lot to blame for the sound however I dont get this problem in stereo (speakers set to small) (Large can do it somewhat) do you also find this?

I would still love to hear from anyone with bookshelf speakers and the 1068 processor running in bypass mode (not the multi input bypass, which as has been said, has the option of directing bass to a sub).

I have gone as far as negotiating a pretty good deal on some matching energy C3 bookshelves to use as mains to try to solve the problem, however this may not be the answer either?

Anyone else have any idea or similar experiences ?

I have sent an email to Energy about the problem to see what they have to say.

Perhaps Rotel could give some insight here as well, I may make a call to them on Monday morning.

Pete

[bleeding ears]

Ok, firstly grit do you run your front speakers as small, master or large?

Bypass with small setting seems more controlled sounding in the bass on my setup.

Ok I actually got a chance to compare my cd and dvd player and there is very little difference, as I said earlier the Onkyo dvd is cleaner sounding and tighter in the bass compared to the Rotel. Very little difference in bypass mode.

As for speaker placement? Well I am very surprised.

I moved the front speakers out from the wall (total of about 24 inches) and yes there is a definite improvement. It has not totally eliminated the excessive bass from bypass mode but it is much better and cleaner sounding.

I cannot leave the speakers 2 feet out from the wall due to WAF,however I may be able to find alternative solutions such as, room treatment or possibly an improvised phase plug similar to that used by B&W.

Unfortunately I dont think Energy have designed the C9 to use a phase plug.

Perhaps a pair of old socks stuffed in the rear port will do the trick? :lol:

Anyone done anything similar?

[grit]

Hey Pete,

I run my speakers as large. When I do run them in small mode, the bass problem decreases, which I attribute to the subwoofer settings. Then again, my sub isn't ported either. I came to the same conclusion you did: either a phase plug (which my speakers did not come with) or some kind of room treatment behind the speakers (for now).

[bleeding ears]

NEWSFLASH: THIS IS UNBELIEVABLE

Major bass improvement through scientific tuning of speakers.

Grit this may interest you.

After trying different players and repositioning my speakers further from the wall, I still didnt get the result I needed. ie (less bass in bypass mode)

I then resorted to more scientific methods, which appear to have worked better than the other things I have tried.

So what did I do? Send my speakers to a sound lab? No!

I stuffed a pair of socks into the front ports and "Yes" definitely much better! Stuffing the rear port alone had little effect, which makes me think that perhaps my speakers were infact not too close to the rear wall. More on that after more repositioning.

I can now play my setup in bypass mode with quite good bass. No need for a boomy sub!

I get the advantages of using by pass mode whilst not getting the bass overkill effect that I previously had in bypass. It appears that the midrange is also better.

This scientific tuning by a master is just the start, I now have to experiment with different phase plugs.

I currently cannot decide on which is best size 10 black socks or extra thick white. :lol:

I may even go a step further and try foam, or rubber or other materials.

Who knows old underpants may even do the trick? :rofl:

Maybe I should give the manufacturer a call and let them know what I have discovered. I might get employed as a master speaker tuner?

If you have bass problems and have never tried this I suggest giving it a go, it is amazing! :T

Sorry about the sarcasm, I am still in disbelief myself.

Oh, If anyone requires my services as a speaker tuner just call.
PS some people just dont take this hobby serious!

Pete

[grit]

:rofl:

Dress socks, or regular cotton crew socks? What about some nylon running socks I have? Maybe the thick, winter woolie socks?

Ok, seriously, my only concern is that blocking/restricting air frow from the port could cause some kind of mechanical damage to the drivers. Anyone able to comment on this?

The other question I have is, where might we find/purchase foam phase plugs, such as the ones B&W sends with their speakers?

[Stevebez]

I think damage will depend on the design ... check with manufacturer if port can be supressed.

B&W 803D's come with bungs ... 802D's dont - not sure why ... seems like overall designs are similar.

Are these phase plugs we talking about or flow port bungs ?

Rgds Steve.

[bleeding ears]

Steve, I could have it wrong, perhaps what I am reffering to is a flow port bung? this is what I thought B&W used.

Perhaps you could explain the difference for me?

Interestingly, I see that some of the new Energy line do use port bungs.

Maybe my sock treatment experiment has already got out at Energy. LOL

Perhaps I could get some to fit my Energy's.

I will also make enquiries with Energy as to whether or not damage could result.

It does seem that the volume level needs to be raised a bit more to get the same volumes as I did before I did the sock treatment, however this could also be that it sounds better and I can listen to it louder. Its hard to say sometimes exactly whats happening.

Apart from the possible slightly lower volume level, there seems to be no other negative effects on the sound, in fact it seems substantially improved.

Anyone know what materials work best for bungs, eg wood, plastic, foam, metal, or just plain old size 10 socks?

I think I read a thread that said aluminium worked best on B&W's

Pete

[Kevin D]

All you're doing is closing off the port, it's highly doubtful that you will cause any damage. Now granted, there's better ways to do it then a sock.

Porting an enclosure boosts certain frequencies and makes the speaker more efficient. The number and length of the ports determines the frequencies and the curve of the boost. That's all related to the size of the enclosure and the driver. When you have a sealed box, you typically have a flatter curve (related to the driver by itself, it may make the speaker less flat), lower extension, and less efficiency.

When you have a speaker too close to walls, this also creates a boost in the mid bass. Sealing the enclosure will remove the ported boost, but should still sound right due to the wall boost. You should expect it to take a little more power, but you should also notice a little more bottom end.

Kevin D.

[Stevebez]

Hi Pete a port bung is what u are refering to ... its generally a round piece of fairly dense foam thats fitted in the flow port hole where the speaker system breathes its bass (well some of it).

A phase plug is a cone shaped center piece generally found on mid range drivers as on B&W's FST driver. CHanging the shape - and some would say even the material - of the phase plug changes the sound characteristics. How or why this works is beyond me but looks like it prevents cancellation / interference of sound from the outer edges of the diaphram with the centre. I am guessing but thats my take... The shape of the plug affects whats cancelled and whats not. Might also help with directing the sound ... dunno!

Hope that helps.

Rgds Steve.

[grit]

Arrite! So, where can one buy port bungs?

[bleeding ears]

Yes, where to get them?

Energy have them on some of their latest C series speakers, I doubt it but it would be good it one size fitted all speaker ports. Am currently making enquiries with energy.

B&W make them, but where to get them and at what cost, I dont know.

Perhaps I will have to make some from foam or similar material.

They may not look very nice but they are mostly hidden within the port and on a lot of speakers the grilles will cover the port so you will not see the bung at all.

Grit did you try the sock method was there any difference / improvement ?

Anyone else know where to get port flow restrictors (Port bungs) ?

Somebody must make them, I am surprised they are not a common item in Hi Fi shops

[Stevebez]

To be honest its not very scientific stuff -- I would look for foam thats allows some air to pass - but does offer some airflow restriction ... also the foam should be of the semi-memory type - i.e. if u push it in there is a depression for a while and slowly it returns to its original shape - this allows snug fit and also generally this foam is more "sticky" to the touch allowing it to remain in situ and not be blown out of the port :twisted: !!

Dont get foam which is too dense!... and mbe have it not more than 3" long ...

Rgds Steve.

[wheelz7]

Bleeding just wondering if you noticed any mayjor difference using clean or dirty socks? I suppose lodgically clean socks would give a much cleaner sound and dirty ones would be abit muddy!

[bleeding ears]

Wheelz7, :lol: , yes excellent idea, I may experiment with clean and dirty ones.

May try beanies, and undies (clean) too.

Female ones may produce a better sound than the male ones which seem to be prone to fart like bass sounds. :lol: At least mine are anyway.

Ok thats it!