Which is the better ALTEC 605-8H or 604-8K

[sajt]

I have bought an original Altec 620 cabinet with 604-8K driver.
I have a pair 604-8H driver. maybe a will change in the cabinet. And after a sale the rest.
Please give some help what do i do?

[pelly3s]

looks to me that the difference is one is alnico and the other is ferrite im pretty sure that is the only difference. then which is better brings up a long debate

[sajt]

yes i know the different (alnico-ferrit) but what does it means? not for a collector, for a listener of music?

[speakerdave]

I believe the H is the last of the Alnico 604's and it also has the "tangerine" radial phase plug in the high frequency unit, which some listeners prefer (and others don't). I think there is a high correlation here between collector and listener value. I would keep those.

But . . . I have neither and you're the man with both. Have a listen and let us know!

David

[toddalin]

Everything I've always heard about the 605 and the one 605 that I did hear (my brother had it) is that it was a real dog with no HF extension.

History says that the Altec 604 was the studio industry standard until Altec came out with the 605. The studios recognized that these had poor extension and that opened the door for the JBL 4330 and 4333. Altec went back to the 604, but the "cat was out of the bag" and the industry never really went back and embraced it.

[speakerdave]

He doesn't have any 605-8H's. There are no 605-8H's. It's a typo. See the pictures.

[Tom Brennan]

I own a pair of 605As in Barzilay cabinets and consider them excellent speakers.

They have excellent bass with a smooth and robust tonal balance. Distortion is low and clarity and dynamics are excellent. They are imaging champs and do all that audiophile "holographic" stuff with the great depth and soundstage extending well past the sides of the speakers.

The highs are somewhat soft, typical vintage Altec. As to whether or not they're not as good as 604s, well I don't worry about it, I enjoy them for what they are.

[Don McRitchie]

The 604-8H and 604-8K do sound different. The following is probably going to make the situation even less clear as to which may be the better choice. However, addtional knowledge can't hurt.

The biggest factor behind sonic differences regards different horn throat geometries as a result of the much shallower ferrite magnet structure of the "K" series that shortened the horn. The concensus seems to be that the "K" geometry works better. However, the "K" series went through a number of revisions and I have no way of deciphering which is which. The very first "K" series are the worst. When introduced around 1980, Altec was going through severe quality control issues, and for the first few years production, the "K" series was quite shoddy with little uniformity between drivers. Unfortunately, the same is true of the "H" series. However, this was compounded by its use of Alnico magnets. In studio monitor applications, the 604-H had a reputation for drifting imaging as the magnets became partially demagnetized during high power playback. It was next to impossible to find and keep a pair in balance. Further the "H" and original "K" series had a notorius spike in response in the 2-4 kHz region. This was not fixed until around the 1982 version of the "K" model. Sometime in the late 80's, the "K" was redesigned again to use the same magnet for the bass driver as the recently introduced 515G. This magnet was larger than the previous version, which gave a boost to mid bass sensitivity, but decreased bass extension.

Even with all of these problems, the "H" and "K" series are considered better than any of the predecessors. Some think that this is because of the use of the Tangerine phase plug. However, the best evidence I have seen indicates that this made virtually no difference in sonics compared to the previous circumferential plugs. What did make a difference was that these series introduced equalization in the networks for the first time. This allows them to have greater high frequency extension and a more even amplitude response.

So whcih is better? Probably a mid 80's "K" version. However, the trick is to determine when any given "K" speaker was manufactured. I have no idea on how to do this. However, in your case, you have both drivers so it should be a simple matter to compare and decide for yourself which sounds best. If it matters, the "H" will certainly get more money on the collectors market since it was very rare and was the last of the Alnico's.

[sajt]

So whcih is better? Probably a mid 80's "K" version. However, the trick is to determine when any given "K" speaker was manufactured. I have no idea on how to do this. However, in your case, you have both drivers so it should be a simple matter to compare and decide for yourself which sounds best. If it matters, the "H" will certainly get more money on the collectors market since it was very rare and was the last of the Alnico's.[/QUOTE]

OK! I will keep, one pair 604E, 604-8H, and 604-8K.

[speakerdave]

OK! I will keep, one pair 604E, 604-8H, and 604-8K.

Ah, yes, a true LH forum solution!

[Titanium Dome]

This site

http://alteclansingunofficial.nlenet.net/Duplex.html

led me to believe at some point the Altec 604 Duplex® might return to production.

This site

http://www.greatplainsaudio.com/2_way.html

leads me to believe that the GPA 604-8H-II Coaxial® is the result.

This site

http://www.altheamusica.com/

somewhat dubiuosly leads me to believe they might be manufacturing a system using this or a similar driver.

Can anyone comment on this?

[Joao]

Hello

yes, we manufacturing speakers with the 604-8L, the Sonore Liberea & Sonore Cassa.

We pay attention is turned to the enclosure. Transfering the resonances in other regions is the solution, and of course the point source. Important are the parts of the x-over. Result is relexed listening and authentic music reproduction.

Just curious how a field coil driver would be a further step.

[Titanium Dome]

Hello

yes, we manufacturing speakers with the 604-8L, the Sonore Liberea & Sonore Cassa.

We pay attention is turned to the enclosure. Transfering the resonances in other regions is the solution, and of course the point source. Important are the parts of the x-over. Result is relexed listening and authentic music reproduction.

Just curious how a field coil driver would be a further step.

Do you have any pictures in addition to the ones on the Web site?


Happy birthday yesterday.

[Joao]

Sorry

don't have any more pictures at the moment. What would you like to know. Please ask and I will answer if it's possible.
You can mail me as well if you like.

Thanks for the congratulations!