I've lost my bass....


Well, not all of it. My system is:

Arcam CD92
Marantz 2020 (Don Scott modified) Tuner
Conrad Johnson PV14
Conrad Johnson MV60
Audio Physic Virgo III
HT Pro 9 Interconnects
Synergistic Research Sig. 2 Speaker Cables

This is my first tube system and I love it. I had this system in a 15' x 23' room and I thought it was outstanding. Mids and highs were exceptional and bass was firm though clearly not registering the lowest octaves. I was OK with that.

Here's the problem. I needed to put my Home Theater system in the room where the stereo was and put the stereo where the home theater was. The furniture and carpeting was also switched at the same time. Now the stereo is in an "L" shaped room that is bigger than the previous one. As a result, the bass repsonse is not nearly as authoritative as it was in the smaller room (no surprise).

My question is, what can be done to improve bass response? Some issues I've thought of are:

1. Room treatment? What kind?
2. Try different tubes (FYI, MV60 is EL34 based amp)? Any suggestions?
3. Amp is underpowered?

I'm open to any ideas on how to improve bass response.

Thanks to all for any help.
Dave
milo
Get a sub woofer. Amp type will only change quality of bass - it won't do much for quantity. Room treatment won't do anything for bass. You can play with the distance the speakers are from the wall to enhance the bass, and with the listening chair to find a room created bass rise. A sub is probably the easiest and best way though.
Try listening with your back right up against the wall - the bass is usually stronger near room boundaries. If that doesn't work or if it's impractical, then Newbee's suggestion is probably the most effective solution.
You do not mention how far into the room the speakers are placed.

As mentioned above, positioning the speakers closer to the wall they back up to will allow the room itself to reinforce the bass response. But too close and things start to get muddy-sounding, as all speakers have different room interaction characteristics, so experimentation is your only option.

Heck, your listening position may actually be in a bass node itself - mine was, and I had to rearrange my entire great room (30'x20'x15' vaulted) to get out of the hole. I only found this out after spending big bucks replacing alot of gear, when my dealer measured my room response with a Real Time Analyzer (RTA). Taking full advantage of the room's shape and features in the best configuration made the single-biggest change in sound quality my system has experienced (and it was FREE!).

Also, Room Treatments CAN significantly affect bass response if you can figure out where to place the treatments to even-out the room modes, nodes and lull-points.

Rives.com and MichaelGreenAudio.com (among others) can help educate you on these principles. This is truly the 'black art' of the audiophile biz...and the only way to get the most out of the equipment that you have.

Hope that helps - good luck finding your bass....
There are some good suggestions by all above. Newbee is correct about playing with the speaker and listening chair placement. The closer to the wall the more the back wall will influence (good or bad) the bass regions.

I'm not that familiar with different tubes or tube amps but I believe there are very few amps that can really achieve that absolute control and visceral punch in the lowest octaves.

However, it seems that you had some of this before, and now it appears to be gone. I do believe that a certain amount of room pressurization helps. The fact that you now have a more open L-shaped room probably does not help matters.

Bottom line is no two rooms are exactly alike acoustically. But there are usually several ways to influence sonics one way or the other.

Does the new room have as good or thicker carpeting as the previous? Also, depending on ceiling height and reflection, your bass sound waves may be collecting and become trapped in the upper corners where the back wall meets the ceiling.

-IMO
I disagree that changing amps will not affect the quantity of bass and there are several reasons why i believe this. The two reasons listed below basically sum up all the various reasons that may fall into multiple different categories though.

1) Various amps are of different circuitry from one another

2) Various amps don't respond the same to various loads / impedances

As such, not only can the solidity, impact, control, definition, etc... of the bass be altered when changing amps, so can the quantity. While i don't think that this is your main problem ( probably room acoustics ), i did want to point out that it is quite possible that changing amps could provide you with a very different sonic presentation over the entire frequency range. Sean
>
A few things to try.

1. Push the speakers either 1/5 or 1/3 out into the room and try moving them around until you hear the bass get stronger. You might want a friend to help you with this. Even better, I would reference the AP setup guide on www.immediasound.com or the cardas setup guide on www.cardas.com. If you follow these carefully, often times you might find a big increase in performance. I've found with the AP's that placement can have a large impact on bass.

2. Try closing any doors. If the speaker has a smaller space to pressurize it will evidence more bass.

3. Try moving the speakers closer and further apart while listening for more bass. Following the setup guides will probably get you fairly close but moving/listening will get you to the place where the speaker is truly working with the room. Just small amounds of 1-3 inches should do it.

4. Clean your interconnects and contacts using contact cleaner. This tends to improve bass. Also try to use the shortest interconnect cables possible and perhaps experiment with cables. I like Nordost Red Dawn on up and Cardas Golden Reference cables with the virgo's. For less expensive I have had good results using Harmonic Tech Truthlink ic's (or red dawn) and Acoustic Zen Satori speaker cables. The Zen speaker cables are a great way to go.

5. Your amp is a on the small side with the Virgo's. I used to run an MV-50 with my old Virgo II's and I recall that it was not exactly a bass monster but still a wonderful sound. I remember swapping in a 185 watt per channel McCormack amp caused the speakers personality to change dramatically - they had much stronger bass. Almost seemed like a different speaker. It was going from 45wpc to 375 so this should not have been a surprise. If the above did not help I would try first using a borrowed/extra amplifier to see if this indeed will solve your problem. Your preamp is also known for slightly recessed bass. I'm not surprised by what you are reporting. Make sure the amp is biased and perhaps try swapping in some Svetlana EL-34's. Those are Mullard copies and exhibit some nice strong bass.

Disclaimer: I do sell Cardas and Audio Physic.
Your amplifier ABSOLUTELY affects your bass resolution and response.
Ever notice that powered Sub-Woofers are usually built with amplifiers that put out anywhere from 400 to 1,500 watts? It is because it takes a lot of power to resolve the lower octaves and control a bass speaker. Low powered tube amps are notorious for producing weak and/or flabby bass. Tube fans typically sacrifice the lower octaves in order to get the reputed liquid midrange and highs. Somehow, the smaller room was configured in such a way as to maximize the bass. This is a puzzle because the lower octaves usually need a bigger room to fully develop.
But, every room is so different and the variables are many. If you want to stick with your gear, the answer is going to be found in speaker placement and room treatment. Might be worth your while to hire an
acoustic consultant to come over for an hour or two and help you tune
your systems to your new rooms, to help you get maximum bass response from your tube gear, bring your system back into balance. Or, you can add a Sub-Woofer. But, I would try the consultant first. He/she
can also help you decide if a Sub-Woofer is warranted and can help you
integrate it into your system. Just a suggestion.

I agree with Sean, the amp can definitely impact bass response. I had a McCormack DNA2 in my system for awhile, and the bass was subterrainian, far better than with any other amp I have owned. However, I couldn't live with the way it sounded in the mids/highs. If you are happy with the overall sound from your current amp, I would listen to those who recommended getting a sub. Get one that is fast and musical, not an HT muscle sub, and one that integrates well with your Virgos, then cut it off as low as possible to achieve the extra bass you are looking for. Doesn't AP make a highly regarded musical sub?
Try a cheap fix first....Put big spikes on the bottoms of the speakers. This should get through the carpet and anchor them to the subfloor. I'll bet this will outperform most of these suggestions and save you a bundle. You could even go nuts and buy some really heavy basses or feet for the speakers?
Do you have the MV60 or MV 60SE? The SE solves the bass problem with the MV60 while giving you more power, bass and speed. The same is true of the PV 14 Series 2. It is well worth the upgrade. Amp stands and room interaction also play a role. I would call CJ and talk to them about your cables. The subwoofer is not a solution. A more efficient or better designed side firing woofer/speaker system is a consideration. I do not think the AP Virgo is the best match for your amps. Keep the amps and change the speakers.
Cellorover, Interestly I think you may have reached the correct conclusion, that he should consider getting new speakers, but for the wrong reason. I suspect the Virgo's are just not capable of energizing the bass in a room as large as the one he now has to use (with any amp!) but personally I see no reason why he should have to find a new speakers and, potentially an amp, when a sub will do. But since you mentioned it, why not elaborate on why a well integrated sub would not work for him and save him the cost and expense of buying new speakers, etc.

Sean, Rsbeck, and others who mentioned the amp - I don't disagree with you in principal, however I didn't see this as a potential solution to what sounded like a substantial loss of bass. Apart from the placement issues I saw a sub as his only viable solution and still be able to keep the Virgos. Recall in his original placement he felt the bass was not outstanding, merely adequate.

Now if his complaint is really just a minor one about bass quality or quantity then the amp becomes a real factor - as I recall the CJ is not an earthshaking bass amp, either in quality or quantity. Perhaps he should get a RS sound meter and a test disc and measure the bass response at the various listening positions and see how far off flat his bass is, and what frequencies need boosting, before he embarks on any revisions. Perhaps he just has overambitious expectations re bass. Perhaps further feed back from the poster would help him get some more specific recommendations.
My suspicion is that if the amp is not producing bass in these speakers, getting speakers with more bass capability will only tax this amp more.
If you want more bass, you need more power. You can add that power
in a couple of different ways. You can trade the low lowered CJ amp for
a higher powered amp, or you can stick with the CJ and add a powered sub, which will come with a built-in high powered solid state amp. If you just want to get the bass response you were previously getting, it is
going to mean tuning the system to the room, finding the right speaker
placement, room treatment, etc. I, personally, wouldn't like having to integrate a Sub-woofer into my music system, so that would be *my* last resort. But, if you are a low power tube fan, I think your options are to give up some bass response, try to maximize it with room tuning, or integrate a sub. No matter what your choice, hiring an acoustic consultant to come over for a few hours could be the best money you ever spent. You'll learn how to place your speakers, the problems inherent in the room, how to get the most out of your system, etc. etc.