How good can D.I.Y speakers really get? - Enter Mr Al Newall

[Clive]

Perhaps the filters are not doing the job properly? I would imagine that may be a possible cause, and as for the effect being greater on one side that may simply be down to to the fact that bass is considerably less directional than mid / treble energy and therefore it would "sound" like the problem is coming from both channels? all hypothetical of course.

Pistonic movement sounds like motorboating, it's possible that any instability is very marginal and only happens with music applied. However it does seem that what I'll call the wideband units were receiving a bass signal they don't normally see. Am I correct in thinking the widebands have no crossover or at least no low freq filter? That should be best for sonics. Possibly bass that you were playing (loud, yes?) was showing up as wideband cone movement but the driver either cannot audibly produce bass at low freq or at only a very low level.

[Marco]

However it does seem that what I'll call the wideband units were receiving a bass signal they don't normally see...

That would be my subjective assessment of the situation. Perhaps 'pistonic' was the wrong word to use to describe the type of movement that occurred.

Marco.

[Mike]

Your system is broken.

Worry I tell you. Worry!!!

[sastusbulbas]

Any pics of these £200 speakers?

[Mike]

Earlier in the thread. The white ones.... I think!

[Marco]

Steve,

Like Mike says, they're the white ones posted earlier

Marco.

[alb]

Clive.

The wide band drivers have a capacitor to cut the bass response below 120Hz. They can sound a little congested in the bass region, when run without these.

We witnessed the same effect when i took them to Ians(another gutsy push pull amp). So i don't think it's anything to worry about.

I have a spare pair of these drivers in the shed, so i'll do some comparisons, and also check the caps again.

I'll post further details of the speakers later, for anyone who is interested.

[Marco]

Hi Al,

I see. I don't remember that happening there at all

You didn't make any comment on it at the time either, as far as I can remember...

Not to worry, but if it is simply the 'push-pull factor', your visit has inadvertently told me something quite significant about SET amps.

Marco.

[Clive]

Al, if it's not a problem for the way you listen then don't worry about it. Just enjoy!

Marco, your needs seem different....Atlas uses two 12-inch widebands and no crossover, now we know why! I suspect that Al has a great speaker (possibly regardless of price) that fits his needs. Your needs probably require greater power handling.

[Clive]

Not to worry, but if it is simply the 'push-pull factor', your visit has inadvertently told me something quite significant about SET amps.

I don't think it's PP vs SET it's more about power and loudness. Ok PP is generally more powerful than SET but that's all. Try some of the powerful SETs with a couple of thousand volts driving the power valve, you'll get the same effect.