830883, 830884 or ER18 ?

I personally like the 883 because the crossover is easier to design than with the breakup of the 884. Yes the seas finish quality is a bit higher but u wont have anything bad enough to affect performance. The motor on the 883 is also brilliant as no zobel is needed. Distortion averages about the same between the seas and peerless tho. So either way id stick with the smaller drivers. Seas if you need its looks, build quality and sensitivity only. But otherwise the peerless is the way to go.
 

Bad_mojo

Member
2008-03-13 3:02 pm
Rounder, Sreten,
thank you both for the replies. I've read good things about Zaph's designs and his site is where I found all these drivers....

Is the 830884 8" worth the hassle for the extra base it can produce? Should the mids be as clear at the 7" drivers?

Is the 830883 not better then the ER18 from 500hz and up? Maybe a better match for the super clean Seas tweeters?

Found some designs that use the Ushers, Are the Ushers worth the extra money and how do they fit in all this?

Mo
 
Hi,

Only you can answer most of those questions.

VFM wise and self build the 8" is the most cost effective compared
to the cost of an equivalent commercial offering, which would be
~ twice the size and price of the 6.5" models.

However "ease of c/o development" is an issue.
If you cannot do it properly use an existing design.

Arguing the pro's and con's of very good drivers is fairly pointless.
They define the quality you can get at certain price points.

Zaph's value ratings I'd say are worth noting.

:)/sreten.
 
As noted above the choice of the 830884 over the 6.5" drivers is mostly size. The 8" requires a large cabinet in order to squeeze out it's full potential in the bass region. My advice would be that if you wish to use a subwoofer in your system, choose the smaller drivers, but if not then you may want to consider the 8" driver for the extra bass extension.

I know it's not exactly what you're looking for since you want to use a seas tweeter, but have a look at my design using the 830884. As far as crossover design goes, the breakup is high enough in frequency and small enough that this driver can be used well in a 2-way design. The issue you'll run into in crossover design is phase alignment due to the larger difference in acoustic centers when using a larger driver.

As far as "best sound"....Terrible question. Best is only what you think it is, so have a very close look at the graphs and numbers available on Zaph's page, and decide for yourself.
 

Bad_mojo

Member
2008-03-13 3:02 pm
DcibeL said:
...My advice would be that if you wish to use a sub-woofer in your system, choose the smaller drivers...

...The issue you'll run into in crossover design is phase alignment due to the larger difference in acoustic centers when using a larger driver...
Prefer to avoid a sub. I've been worried about the vertical distance between the two acoustic center causing strong lobing. To make a make a real difference I might need to go to back to a 5 1/2" or smaller even. Is that worth it? Might not be. Can anyone confirm if my thinking is more or less accurate?



I know it's not exactly what you're looking for since you want to use a seas tweeter, but have a look at my design using the 830884.
Looks really nice DcibeL. Glad to see someone made the big 8" work in a 2-way. Hope you don't mind I got tones of questions for you...

How do you find them on rock music in general? How do you find female vocals?

How loud can you play them before they start to loose some sound quality?

If I understood correctly, in your final x-over you crossed at 1500hz?

Since you've had them, have you noticed any AUDIBLE problems caused by the large distance between acoustic center? Are you confined to sitting in a "sweet spot"? Does the sound quality change allot when moving about the room or stand-up?


...As far as "best sound"....Terrible question...
I know. This speaker business seams to be all about compromise. Just worried about muddiness in the mid-range. Any sign of it in your system?

By the way, do you know if Zaph's measurements are based on the "made in Asia" or made in Denmark version of the 830884?

Thanks for your post DcibeL, sorry for all the questions but that's what you get for showing off:)

Mo
 

marchel

Member
2007-11-18 4:51 am
"By the way, do you know if Zaph's measurements are based on the "made in Asia" or made in Denmark version of the 830884?"


I think both are made in asia. The difference between the 2 are the cone and the sticker in the back . I,m not sure whether there are difference in TS parameters and sound quality, BUt there must be.

I have 4pc of 883 for my 2.5 way project, Knowing that there are inconsistencies, I made sure to tell madisound to give me the 4 883 of the same production batch and they did.

If you'll use the 884 , Dont forget to tell the vendor to give you drivers of the same batch as I did.

BTW , Here is the project I'm talking about , it is not yet finished tough, so I cant comment on ow they sound, But I hope they would sound good. Linl to the project
 
Bad_mojo said:
How loud can you play them before they start to loose some sound quality?
In my design, the drivers will run out of excursion at around 30W at 30Hz. This is a result of the low port tuning I chose. How load you can play them is dependent upon your design, and is a combination of the cabinet and crossover that you use the drivers in.

Bad_mojo said:
If I understood correctly, in your final x-over you crossed at 1500hz?
Yes. Roughly 4th order acoustic on both the woofer and tweeter.

Bad_mojo said:
Since you've had them, have you noticed any AUDIBLE problems caused by the large distance between acoustic center? Are you confined to sitting in a "sweet spot"? Does the sound quality change allot when moving about the room or stand-up?
No sweet spot to be found. I was very suprized to find just how far off axis I could be and the speakers still sound great. Keep in mind that a null due to lobing is much less offencive on the ears than a peak. All this of course is not purely a function of the driver selection. It is a combination of crossover design (order and frequency), and the location of the drivers on the baffle.

Bad_mojo said:
I know. This speaker business seams to be all about compromise. Just worried about muddiness in the mid-range. Any sign of it in your system?
Again, proper interpretation of the graphs available should answer this question for you. What do you think "muddiness" is a function of in the speakers you've heard? Poor frequency response? Poor phase alignment between drivers? High distortion? A combination of all the above? I encourage you to read up on how each of the above problems affect the "sound" of the speaker, and know that all the above can be simulated in software prior to building to get a good idea of how things will be. The drivers are only one ingredient in the recipe.
 

Bad_mojo

Member
2008-03-13 3:02 pm
DcibeL said:

In my design, the drivers will run out of excursion at around 30W at 30Hz. This is a result of the low port tuning I chose.

I would be tempted to say I would port them low and lean as well. LOL how loud does 29W get? Is it close to a crazy teenager party? or just too loud to enjoy for too long of a period of time? I really want to blast my speakers from time to time. :)


No sweet spot to be found. I was very surprised to find just how far off axis I could be and the speakers still sound great.
Glad to hear it!

Poor frequency response? Poor phase alignment between drivers? High distortion? ....know that all the above can be simulated in software prior to building to get a good idea of how things will be. The drivers are only one ingredient in the recipe.

Spoken like someone who has already built a speaker!

Thanks for taking the time DcibeL,
Mo
 
Bad_mojo said:

I would be tempted to say I would port them low and lean as well. LOL how loud does 29W get? Is it close to a crazy teenager party? or just too loud to enjoy for too long of a period of time? I really want to blast my speakers from time to time. :)
Mo

Hi,

A 30w amplifier running widerange at clipping level would hardly ever
overload the speakers in terms of bass excursion, though there is
always that rogue signal. Generally low bass is not recorded at full
modulation because most speakers cannot handle it.

I'd estimate realistic power handling at over 150W per channel
programme, i.e. good music material clipping occasionally, not RMS.

Obviously cranking it up excessively with material that has lots of
specifically deep and low bass (or subsonics) is not a good idea.
If this appeals I'd say a subsonic filter is mandatory.

How loud will they go ? basically depends on room size and
the amount of juice that can be applied. Crazy teenage party
is turn up everthing until it sounds painful, at this point you
are risking losing your very expensive tweeters. Never use
hi-fi speakers for less than civilised parties, borrow or hire
some PA speakers that are & do loud (but no real bass).

:)/sreten.
 
ER18 / 27TDFC Comments

As you may know, I've built an MTM using ER18RNX and 27TDFC in a bass reflex enclosure of about 40 litres. I had a lot of help from Jay with the crossover.

These are extremely good speakers.
Sensitivity is high enough to work very well with my 300B SET amp.
Peformance is very balanced, in that they do everything well.
Bass is tight and controlled, tuneful, has good extension and 'slam'; yes, lots of good tight dynamics in the bass with 6.5 watts of SET power ... amazing.
Dynamics generally are very good indeed; startling! The previous speakers just didn't do that.
Tonality, tunefulness are excellent - very important for classical music I find, and this sounds superb.
Female vocals are just beautiful! Not rounded off or smoothed over, all the detail is there; it's just presented without harshness, giving reality, a tangible feel, really lovely. Mo, you did ask about female vocals - here's your answer.
I have a special liking for good female vocals; my previous speakers did this very well, but these are better! They have more detail, and at the same time the lovely midrange of the 300B amp does wonders. Very spine tingly and enjoyable.

Mo, you also asked about rock; well these MTMs are very good for this, with plenty of rhythm, drive and bass slam. I think the area of the twin bass drivers has a lot to do with this.

This may seem an over gushing biased post; I've been trying to think of something not-quite-so-good to say about them, honestly, but I can't.
Jay's site has details of course. My version differs slightly as it was optimised for the SET amp (and this worked out very well indeed).

As for your specific questions: you can't go far wrong with the ER18; they do female vocals exceptionally well; and as an MTM with the right enclosure, they will certainly rock and personally I'd say they don't need a sub.
 

Bad_mojo

Member
2008-03-13 3:02 pm
MikeC,
thanks for sharing your experience. I'm glad to hear your speakers are pleasing you. I must admit I am very tempted but just don't feel comfortable with an MTM setup. I do like the idea of never having a need for a sub by having two woofers per enclosure. Also like the look of it. I would prefer a 2.5 TMM with the ER18 or the 830883. Would a 2.5 TMM with the 830884 be able to gain anything over the 7" woofers interms of the midrange? I could settle for a plain Jane 2.0 TM setup with the 830884...

All this to avoid the narrow vertical "sweet spot" of the MTM. If Jay is reading this... do you have any comments on this?

Mo