Look at my new babies...Altec 846Bs w/EV Tweeters!

[Zilch]

I still can't believe that you guys doubt me....

Make that singular, Storm....

[Shane Shuster]

Thanks, Shane.

45° is kinda extreme, but there's certainly nobody home in VHF out there.

I can't figure the horizontal scale very well. At what frequency is that cliff in the HF in your first plot? 7 kHz, maybe?

Is the driver running on any kind of filter?

If not, it looks like that one could be compensated, assuming, and that is a BIG assumption, the horn would support it....

5.5 khz is where it starts to drop, 7khz is where it stays and slowly drops a couple of db until 12k where it falls off again. (0db at 5.7k -9.1db at 20k)

I took a 45deg one because I can still hear to 20k and thats one of the things that bothered me about the Altecs. I would move my head a little and the treble would change or if I was moving around and still wanted to listen to music they didn't have much treble.

As for a filter its just a Solen cap (27uf) with nothing else.

I used to force re-voice my Altecs with the Tact. They will take eq but its not without compromise.

Sorry about the blurry screen caps but my monitor is big and I had to resize them down quite a bit.

[Shane Shuster]

How do you normally play these? In what system?

Currently I play them in a cardboard box, in storage.

[Zilch]

I used to force re-voice my Altecs with the Tact. They will take eq but its not without compromise.

How's that? Sound nasty when you try to EQ them flat? Beam at HF?

These are important factors when considering whether to use compensation as in M19 and augment, or convert to true three-way, in my experience. Compensation works in JBL's 4430, but it graciously desists ~16 kHz. I was informed today there's a different Altec crossover with compensation to evaluate, also.

With the JBL exponential/lens combination, if I boost the VHF, it plays to a progressively narrowing horizontal slit. A major advantage of adding a UHF driver like 2405 is to restore vertical beamwidth (albeit briefly, as the slot itself beams vertically.)

Give us a bit of context here, please. What is Tact?

[Shane Shuster]

Sound nasty when you try to EQ them flat? Beam at HF?

Nope. It was a night and day difference. I did not run my Altecs without it. Sounds much flatter. Gets rid of the "horn ringing" most guys try to get rid of by using putty but which is actually the somewhat ragged frequency response. When you turn them up the electric guitars don't blare notes as much. (ie, stock at moderate volumes it sounds like a 5 string, 10db louder it sounds like a 4 string, ect) Obviously it doesn't fix the dispersion pattern and you do loose the ability to play really, really loud because you are boosting and cutting with the EQ. Also it added a very low level of high frequency hiss which I personally can't stand. If you can't hear all the way up or are a normal, well adjusted person you would never notice it. I would say it's not 100% transparent. Even with the EQ set to bypass you can tell something was added to the chain.

I should point out that I had DIY Altecs. I made the box (5cu ft) the same width as the 511bs but made it taller and less deep so the center of the horn was at ear level when seated. I braced it good, but not Widget good. The woofer was as high in the cabinet as I could get it, without weakening the box, so that it was closer to the horn. I had the front of the horn secured and also the back with a bracket I made. I placed the horn according to the literature in the Altec library on this sight for time alignment and used a 2nd order 500hz crossover.

Give us a bit of context here, please. What is Tact?

Its like a DEQX but its less geared towards pro tweak ability and more for consumer use. You take a mic measurement, draw in what curve you want and it makes a filter. It does frequency and time alignment. Its all digital and can be used as a preamp also. It works great for what it does. Some speakers (like maggies) it did not work well on. Altecs it worked great on because they had headroom to take the EQ.

I found out, however, that I am not the kind of person who can have an eq in their system because I get it set perfectly. Then a week goes by and I listen again. It's not right! Tweek tweek tweek. It's perfect. Then I listen to a different kind of music. It's not right! It's just too many variables added and not enough listening to music for me.

[Zilch]

It's just too many variables added and not enough listening to music for me.

Despite feeling like a magazine interviewer here tonight, I'm not gonna let you get away without telling us the conclusion. Have you found a more satisfying approach? Sounds to me like you put the DIY Altecs away, then?

[sourceoneaudio]

I still can't believe that you guys doubt me when I say they are now listenable without getting fatigued, compared to stock 846's.

If you dont have a pair to compare them to, stop arguing.

Thanks.

-Storm.

Storm,
The question is are you ready to compare? I will be ready in about two weeks to have you over if you want to have a listening session. I go in for surgery on Monday so I will be down for the count for a while. Let me know.

J/S-S1A

P.S. Your 846's are stock except for the tweet addition. I have compared your factory x-over to another and it has not been modified. This one is OEM.

[Robh3606]

I used to force re-voice my Altecs with the Tact. They will take eq but its not without compromise.

Any horn that uses directivity to flatten the HF response on axis will have an issue with EQ. There is no way around it as the power response does not follow the on axis curve and when you use EQ, for the most part you are adjusting for the power response in the room. Take a look at this. It does a good job explaining this.

http://www.audioheritage.org/vbullet...ead.php?t=6687


Rob

[flyhero]

very nice!

[Zilch]

Since it was mentioned that Don has M19s, here's his take on them from less than a year ago:

http://audioheritage.org/vbulletin/s...ad.php?t=11484

[Storm]

Zilch,

Are you the only one that understands why I like these so much with the added EV T-35 tweeter?

Argh.



-Storm.

[scott fitlin]

No, I understand too.

With a tweeter, you get a certain crispness to the very upper midrange, as well as sparkle in the top end. Makes music sound right and opens up the image. And a horn going all the way up, no matter how high it can go, just doesnt do it quite the same.

[louped garouv]

No, I understand...

me too.....

[spwal]

Hi,

Im on the tweeter bandwagon, assuming it is reversable. I would like to be a guinea pig.

Please let me know what i need to do on my end.

thanks

[Zilch]

Are you the only one that understands why I like these so much with the added EV T-35 tweeter?

Nope, seems like most everybody gets it, actually.

Here's what I've learned so far from this, though we need more measurements to be certain: Valencia (806A on 811B horn) has poor high frequency response. It drops 10 db between 1 kHz and 10 kHz, and then crashes above that.

Previously, in order to hear the high frequencies, you've had to play the horn at a higher level than the woofer. That artificially boosted the midrange as well.

With the tweeters, it's not necessary to boost the horn, the system is better balanced, and the midrange is more clear.

In the bigger picture, VOTT and its derivatives were voiced for the theater, (vice-versa, actually,) and do not translate directly for home listening....