Lets get back on topic here. I'll respond to Jeff later on the other thread.
BillWojo
Poor mah, poor Wojo, they are coming apart at the seams !! Right before our eyes.
G-d forbid, someone mention listening to music as a "test" of equipment. Ohhh no, ya gotta have a written paper on file, even if its WRONG, but it must be published, and an EE degree is the ticket to the truth..
What the heck will a hearing test tell about listening to music reproduction in a home environment. I want to remind you all, its FAR more complex than the simplistic EEs theories would have you think!! mah, you are grasping for straws, attacking me, when you ask for a hearing test. Its hilarious, what you are, ( which I despise ) and how you act.
How can one explain that 80 year old woman on Robert Fulton's listening panel " Who couldn't hear a watch tick", say " Whats happened to the highs" when Robert Fulton removed the fuses from his "big" speaker system, which came-in from 42 KHZ on up, and extended to 80 to 110 kHZ ???????? Resultants come down into the midrange, and any good, experienced listener will KNOW whats good and what doesn't cut it !!
How old is Bill H at GPA ?? He KNOWS whats good !!
Also, If I don't have " credibility " according to mah, please consider my two audio mentors.
My first mentor, ( 1978-1988 ) Robert W. Fulton, OWNED / RAN an audio company, had one of TWO of the best rated speakers made, on the face of THIS earth, according to Stereophile's founder, J.Gordon Holt - for high end audio.
The other speaker system Gordon Holt suggested at that time was a Infinity ServoStat system, which was Arnie Nudell's company. I personally knew both these guys, Arnie was local, would buy Decca cartridges from me, and at one time or another, I ran BOTH of their speakers in my own apartment. What was mah and Wojo listening to back then, I'd love to know. What would their sound systems sound like to ME, ( not them ! ) IN their homes, today, in 2017 ???
My second Audio mentor, ( 1988-2017 ) heavily helping me in the last ten or so years, ( as I got back into ALTEC and high efficiency speakers ), is Dennis Fraker of Serious Stereo, Livingston, MT. What are HIS credentials.?? Well, I have mentioned them more than once.
In 2005 ( Stephaen Harrell, Six Moons Audio ) and in 2016 ( Stereophile Magazine, Herb Reichert) gave Dennis Fraker FABULOUS reviews for his demos those years at the big RMAF Denver audio show. Read them. They are on line.
Mr. Harrell seemingly got "into" 604s as a result of visiting Dennis' RMAF room. Read about, and see photos of Mr. Harrell's subsequent GPA / ALTEC 604 journey, here :
6moons audio reviews: Steph?n's Altec 604 Dream Speaker
And here, below, is Mr. Harrell's assesment of what he HEARD, at Dennis's room, in 2005:
6moons.com - industry features: Rocky Mountain Audio Fest 2005
Both reviewers saying ......best sounding room at the entire show, out of maybe 200 or 300 audio exhibitors in the audio business, each year.
On a very personal note, Mr. Futon played a huge role in my life. He, ( primarily by his consistent Christian conduct ), led me to eventually accept Jesus Christ. Mr Fraker, led me to having the best possible amplifier, within my means, for me to enjoy in my home hi fi. Fulton was, and Fraker is, ....a cherished friend.
***** mah and Wojo, I am NOT Mr. Fulton, and I am NOT Mr. Fraker, but I am fairly confident I am hearing about the best there exists, especially on ALTEC / GPA, or CLOSE to it, and I will always respectfully tell you and others the truth as I know it. *****
Listen up Wojo. There really IS only one best,..... it is, by definition, singular !!! Insulting you??... so sorry. That is just the way it is. I won't back down from speaking my mind.
I don't have to prove it. You two don't even really have to understand. I don't worry much, what you two attackers think.
I may make errors from time to time. But remember this .............The proof of the pudding is in the eating.
Back to the subject of this thread, the wiring information I clearly outlined in this thread, is part of the equation that " won the RMAF show" in 2016 - on GPA 604s !! Do as YOU please!! Its nice for me to get to know you all.
Have fun guys and girls, I sure do !!
Jeff Medwin
Last edited by LowOhms; June 24th, 2017 at 05:00 PM.
Lets get back on topic here. I'll respond to Jeff later on the other thread.
BillWojo
I wanted to update my progress. I have got the systems up and running. But I will be re-doing the wiring after studying in more depth the posts. I did the wiring before some of the posts that discuss some specifics were posted. M22579/11 16 and 18 AWG in lengths mentioned. My take on Low Ohms and GM's posts is that it would be preferable to have the speaker "internal" wiring with wires separated- not twisted- or even touching. I will study and ask for clarification.
My initial impressions:
1) I was expecting there to be weak bass because of open baffle design. (mentioned in posts on these) I am not hearing this- bass is beautiful, harmonic, ample amplitude, and "has great air". Why? Small room and placement? Firing angle about 14 degrees off wall perpendicular, baffles about 8" apart at center, placement close to wall? Can move a lot of air without clipping the 8W amps. Charlie Louvin "I'm No Longer in Your Heart"- Johnny Cash "Dark as a Dungeon" at volume is quite and experience. Well studio recorded Nashville country from the 60's is IMO some of the best recording technique- and is a good match to the 300B amps and 604's.
2) I am not gonna take a position as to recommendation- that said, I wil say that these OB's worked out way better than I thought they would.
3) I believe an advantage of OB's is lack of signature of any type of box. As name implies: "open".
4) So far somewhat of a downside is that (as with most speakers I've had), the 604's seem sound better at volume. Maybe a possible downfall of OB's. I'm reminded of the old systems that used to have "loudness contour". (Of course my hearing's not so great- 69 yrear old mechanic) One of my other speaker sets is Fostex FE168 Sigmas in Nagaoka folded horn enclosures from Madisound. The Fostex/BLH's sound better than most speakers at low volumes- and have good dispersion at angles.
I will post more specifics and photos of build for the record- and in case any one is interested. Pictures a little dificult with 95kb forum limitations. Thanks so much to all......
Neat work. Interesting project.
Think about the length of those short wires compared to the many yards of wire in the crossover inductors. The very very very very short lengths of connecting wire have extremely low capacitance and inductance compared to the values in the crossover.
That is why Altec used smaller size but properly current rated wire in their crossovers. Twisted or parallel or separated? Larger gauges of cable have higher C than lower gauges due to larger conductor spacing. Twisted wire is more resistant to external electromagnetic influences. At the length shown in your pic, insignificant. If there is hum or noise or crosstalk the problem is elsewhere and not due to your crossover wiring
Last edited by mah; June 25th, 2017 at 06:43 AM.
Opinion is only as valid as its verifiable supporting evidence.
Got tired of over thinking, decided to use Belden 9497 and be done with it.
Your neighbors called. They like your music.
Neat wiring.
You write " I have got the systems up and running. But I will be re-doing the wiring after studying in more depth the posts.".
Here is what I suggest, using the 8 Watt 300B amp:
Your losses are presently way too high, and your transfer efficiency is highly compromised, as wired.
Wire lengths, crossover to drivers, need to be the same, .....your tweeter looks longer than your woofer length, ....... slightly.
(1) Speaker input terminals to crossover: Use double 12 AWG Mil Spec, for each polarity, 14 1/4 inches to the crossover board. wires don't touch.
(2) Crossover to woofer, same as above, double 12 AWG for each polarity, no touch, and tie wrap each each lead to the " spoke " on the speaker basket to eliminate tugging destruction. Suggest 28 1/2 inches for your specific length, for BOTH sections of the co axial. Eliminate totally use of the stock ALTEC woofer press-to-fit connectors and CAREFULLY and QUICKLY solder directly to the terminal that holds the voice coil wire, on each polarity.
(3) Crossover to tweeter. 28 1/2 inches, M22759/11 16 AWG, single run, no-touching. I personally like to eliminate the press to fit, and solder ( quickly, carefully ) to the diaphragm. Cover woofer and driver s with clean rags, when soldering to them. Remove rags, of course. ' Sounds nicer under drive.
(4) 300B Amp to crossover. NO TOUCH and equal lengths. Use two Fulton 57 1/8th inch lengths, or three, IF really needed, of your own self-made speaker wire. Try double and / or triple 12 AWG, m22759/11 12, and CAREFULLY A-B that against Audio Research wire, after executing (1) to (3 ) above.
( I use two Fulton lengths and tripled-up Mil Spec 12 AWG m22759/11 12 on my VOTTS, with a 1.3 or a 3 Watt amp. ) Each polarity is lightly drill twisted around itself, but NO-TOUCH, one polarity to the other, amp output to drivers..
Use what sounds BEST to YOU !!!
Have fun, if you have any questions, contact me.
You will have very good wideband transfer efficiency, as I have outlined it.
Don't worry about the length of wires in your inductors, they are fixed, and you have little control over the AWG, unless you replace them. Just use the shortest possible length of the inductor's wire, as it comes OFF the winding.
Have fun HEARING this, I sure do ! Tell us about before-and-after. Nice report so far !!
Jeff Medwin.....Low Ohms.
Last edited by LowOhms; June 30th, 2017 at 10:54 AM.
Re-posted this photo on other thread ( MAH vs LOW OHMS ), see page 4.
Mass - Loading Speakers, for Extra Performance gains - drlowmu - High Efficiency Speaker Asylum
Last edited by LowOhms; June 25th, 2017 at 05:13 PM.
Originally Posted by kipduff
1) All of them plus baffle design, though as a general rule the room dominates below ~250-300 Hz, so a big variable and why so much technology, etc., is devoted to studio, cinema, etc., room design.
Baffles are acoustically close too, so there's summing going on down low and the 8" gap is slot loading front to back radiation to boot. Raise them off the floor some and you may get a bit more slot loaded bass out of them.
'Great air' is lack of acoustically small box syndrome. Perch a 400 lb woman on your chest, then try to sing to get a keener understanding.
4)As a general rule, HE speakers need a 'loudness control' to tonally balance the speaker over its LF - lower mids bandwidth, which the 604-8K's XO tone controls are for [what the BLH does acoustically], but you don't have, so guess whatever you've got doesn't have [enough] shelving built in for OB loading. Anyway, today we call it a BSC [baffle step compensation] filter, so you can either modify yours or add a custom designed fixed or adjustable one to add in series of each speaker: General Speaker Related Articles
GM
- - - Updated - - -
My take on Low Ohms and GM's posts is that it would be preferable to have the speaker "internal" wiring with wires separated- not twisted- or even touching. I will study and ask for clarification. Thanks so much to all......
You're welcome!
Then you misunderstood mine. In short, 'twisted' is the century + proven way to wire for minimum signal degradation.
WRT wire size, it's all about voltage drop over distance, so there's plenty of sites with all the necessary info to accurately calculate any length wire run, how much [fractions of] dB difference it will make, etc., but for 'giggles' here's a 604's period correct frame of reference........... in a late '40s - mid '50s era [based on pics of studio gear] RCA Recording Studio and Sound System Architectural and Engineering Manual, the wiring size nomograph only considers 22 ga - 14 ga wire sizes and if longer/larger is required, then run multiple 'twisted' conductors as required.
More pertinent to the 604-8K wiring in a typical HIFI/HT app [assumes a ~10% power loss over distance]:
8 ohms nominal [one half of total length required]:
22 ga = 15 ft
20 ga = 22 ft
18 ga = 38 ft
16 ga = 60 ft
14 ga = 95 ft
This was off a log-log chart, so just 'eyeballed' and could be off a foot or two on the longer runs, but it's obvious that HE speakers don't need large wire unless you want them to do double duty as frequency shaping filters as the tradeoff of less power loss over distance, which at ~10% represents an inaudible difference in dynamic headroom with HE, low power rated speakers.
Better IME to design for least signal degradation and add outboard [adjustable] filters to fine tune the system to suit one's app, hearing, etc., than relying on someone else's perception of what it's supposed to sound like.
This is based on cotton braided, rubber insulated copper wire [solid or stranded], so without checking, guessing modern insulation will allow even longer runs for a given wire size.
Notes all speaker wire runs be twisted and withstand a 600 V hi-pot test*. In a sketch they make it plain that all speaker signal wiring be twisted, so this includes XO wiring, etc., too.
Notes that signal level differential between speaker, electronics wiring is great enough that crosstalk isn't an issue, though power lines and/or multiple discrete signals can, so isolate from power cords and between bi-wiring, multi-amp wire runs.
* 'Megger' test nowadays.....something sadly lacking in DIY system builds as this 'lights up' any wiring, component 'shortcomings' in the signal chain.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
We do a lot of megger testing on commercial aircraft these days. Its not good enough to just check for continuity and shorts to ground with a regular DMM. We megger most of the wiring. It checks for insulation breakdown and problems to come.
The megger uses high voltage (either 500 or 1000 vdc) to test the wiring to its neighbor, or to ground. For me, anything over a few meg ohms is open. Some tasks specify a certain reading. Like over 150 meg ohms.
Hi GM,
To twist, or not to twist ??
It may be " centuries proven " as you suggest, but it is not always the best way to execute it, if one simply listens.
I have recently been able to listen to wires, twisted and untwisted, and ....in certain applications, ....untwisted sounds better to me . Two specific examples follow :
(1) In a transparent SET amplifier, the end-to end ( outside wires ) of a power transformer's high voltage secondary windings leads, going to a rectifier tube, sound best if NOT twisted. ( The 5 VCT filament winding to the rectifier tube, however, NEEDS to be twisted. ) I believe there were two people who already independently made such conclusions, Jack Elliano was first - long ago, and recently, Dennis Fraker, both Manufacturers.
(2) For between power amp to driver runs, I have recently A-Bed this, ( this month ) and on my system, polarities not touching clearly sounds better. In fact, ANYONE would plainly hear this on MY system.
Although the decades-old EE books denote what AWG works for so many feet, and I appreciate you showing this to us all..... I suggest that their assumptions may need to be questioned, re-evaluated, as being ...not adequate. It ass/u/mes a 10% loss. Is that ....a good assumption??
My first audio mentor, Robert Fulton had a saying I like a lot " An inch of bad wire can ruin the musical experience ". I agree with him, while at the SAME time, I seek to show absolutely no disrespect to you, and your MANY contributions to ALL of us !!
I would hope this Forum is " big" enough to allow some diversity of thought. Non touching of polarities, in the two areas I have mentioned herein, ( H.V. winding and amplifier-to-drivers ) were specifically ( and purposefully ) used in the RMAF demo room in 2016 by Serious Stereo, and they will be again, this October 2017.
To see a photo, taken by the Stereophile magazine reviewer, access the URL below, and look at the photo of the two monaural RED JJ 2A3-40 power amps, and VIEW how all the leads are very carefully orientated !
RMAF 2016: Sunday at the Show with Herb | Stereophile.com
I discovered the results of " no touch " in MY system, only about ten days ago, and was ecstatic over the new and positive results. I seek to share that with others. What I HEAR, always trumps any decades-old written theory. If it sounds better, it is better IMHO.
If you personally A-Bed this, and clearly heard it, what would YOU do and / or think ?? Reality trumps theory. Results matter.
Respectfully submitted,
Jeff Medwin.....Low Ohms.
Last edited by LowOhms; June 28th, 2017 at 06:53 PM.
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