Dunlavy SC-IV bass problem


please help that I bought a Dunlavy SC-IV speaker. But, I found the bass of the speaker is not enough. It seems missing some range. I am sure that the speaker driver (Vifa) is work well.

Can someone explain bass problem of Dunlavy SC -IV and teach how to modify it to new version(to use scan speak woofer driver)?

Thank you.
Explain what the exact problems are. Are both speakers not producing bass or just one?
What amplifier are you driving them with, could be underpowered??
Are both speaker in proper phase?
Don't change woofers unless you are prepared to redesign the crossover.

If you really want more bass, I suggest having the woofers' T/S parameters measured to see if it's feasible to port the cabinets. Otherwise, woofers that give you "more bass" in a sealed box will also be lower in efficiency, necessitating a significant crossover modification to restore correct balance between the woofer and the other drivers.

The easier solution is... get a sub and use it to gently augment the low bass region.

It is "missing some range".
what amp? Might be the your using is to low in power and the bass is suffering. Tell us what amp your using? And a high power SS amp could be all you need to fire them bass drivers up.
Quality over quantity? Less distortion?

Was it Stereophile that classified it as "limited"? Then again, John Dunlavy pretty much said the same about Stereophile.
Be sure and check the phase as Brf said. I once heard a very large pair of speakers at a friends house, I told him they didn't have much bass, he said nonsense. A couple of months later he found that the factory had wired the woofers out of phase.
Hello all,

I am using Accuphase power amp P600 and pre amp C240. I think the power of amp should be enough.

The speaker is bought in second hand shop. It is like new. I trust there should had no user to modify it before.

Can someone give me information to identify my own one?

As for bass response,

1) I found that the sound of mid and high driver is louder than the bass. I just hear the mid and high driver. I need to tune them down and then the bass will be better or more bass I heard.

2) I feel some stranger in bass range. It seems missing somethings but I do not know how to say that. I need to open it to check is the wire out of phase? However,

Before opening it up, I would like to point out that both side speakers are same sound quality. So.........

My friends and I feel problem in bass!!!! But, I can not find other users in Hong Kong to make comparsion.

Can someone instruct me how to do it?
There was a thread 8 years ago about a guy who modifies the Dunlavy speakers.
You can check the polarity of the wiring on the woofers with a battery.

Connect the + battery terminal to the + speaker input, and the - battery terminal to the - speaker input. The crossover will send the DC voltage from the battery to the woofers, so your mids and tweeters will be safe. Both woofer cones should jump forward. Check this on both speakers.
Speaker and listener placement has a _lot_ to do with the bass you get out of your speaker. After moving to a new home/room I needed to move my seat forward six inches to avoid a noticeable suck-out.
I think you need more power on the amp(s). No more weak bass after biamping the SC-IV with 2 amps, one tube and one SS for the lows.
Jjff168, your bring back a 3 year old thread with a dumb response.
The guy was using a Accuphase P600 amp to power the Dunlavy 1V speakers. .
That Accuphase amp is like 90 pounds and built like a tank.
Its 300 watts.
That is plenty of power for the bass on the Dunlavy 1V speakers.