Classic monitor designs? Classic monitor designs? - Page 44 - diyAudio
Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

Classic monitor designs?
Classic monitor designs?
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 21st July 2017, 09:56 PM   #431
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Some extra info on the (Soni)kit models (from mpbarneyspeakers):

The sloped front baffle time aligned pyramid shaped enclosures in the model C satellites predate many that have copied it was first used in 1978 IIRC.

Fried often wrote and discussed how important phase, amplitude and magnitude are in a speaker design.
He was also one of the first to use polypropylene cones and double stacked magnet structures in his TOTL speakers.

"The Fried B/2 is a mini-monitor speaker, marketed in the late 1970s, starting in 1978. It competed in a market segment that included the Rogers LS3/5a, JR 149 and KEF 101, among others (shown in the last image below). It was sold both stand-alone, as the Model B/2, and with a separate dual channel, single box, transmission line subwoofer called the Model T. As a package, the three piece satellite-subwoofer combination was called the Model H/2, shown below. It was sold both in assembled and kit form. One dealer (Sonikit)'s prices in 1979 for the B/2 were $600/pair assembled, $420/pair for the kit version including cabinet kits."

The Fried Model H speaker system was sold in the 1978 timeframe as both a kit and assembled system. Designed by Irving "Bud" Fried, it was the first satellite-subwoofer system. The satellites consisted of a KEF T27 tweeter and B110 bextrene cone midrange (the same drivers used in the LS3/5a speaker of the same vintage) in a sealed cabinet. The woofer consisted of a single cabinet housing two separate transmission lines driven by a KEF B200 SP1022 bextrene cone woofer as both a kit and assembled system. There was no crossover in any of the cabinets, instead, all crossover components were housed in an aluminium chassis seen atop the woofer in the photo below.

The original B model used the KEF drivers. Also the T, O and Super Monitor subwoofers used OEM Dalesford subwoofers.
These models used a first order parallel crossover, while he was experimenting on series crossover circuits that were later used with the C2 satellites and O2 subwoofers.

Fried started having his drivers sourced for the B-2 and C satellites around 1977. The B-2 used a 6.5" OEM Dalesford bextrene cone driver made up until 1981, with the Dynaudio D-28H tweeter.
The second version used Scan Speak 2008 tweeters. The poly cones used in the C2 satellites and O2 subwoofer models were made by Transparent Sound which also went out of business.


What Fried produced were full range, efficient, first order/serial crossovers, wide band main driver, transmission line loaded, very coherent and dynamic loudspeaker systems.


Note:
The last image below shows the Fried Model B/2 along with some of its contemporary competitors. Left to Right: Fried B/2, Fried Model B (the B/2's predecessor, also used as satellite for the Model H), Rogers LS3/5a, and JR149. Note that except for the B/2, all of these speakers used the KEF T27 tweeter and KEF B110 mid-woofer.
Attached Images
File Type: jpg SONIKIT Brochure Front.jpg (84.7 KB, 134 views)
File Type: jpg FriedH2fromSonikitbrochure1978.jpg (103.5 KB, 132 views)
File Type: jpg FriedHsetuplikemarketingdrawing.jpg (91.9 KB, 133 views)
File Type: jpg Fried B2 Mini Monitor.jpg (140.9 KB, 131 views)
File Type: jpg Fried C Pyramid & Super Subwoofer.jpg (169.9 KB, 121 views)
File Type: jpg FriedB2Sonikitbrochure-page2.jpg (372.4 KB, 15 views)
File Type: jpg FriedB2cabinetplans.jpg (107.5 KB, 14 views)
File Type: jpg FriedH2brochure-page2.jpg (320.4 KB, 18 views)
File Type: jpg FriedH2brochure-page3.jpg (314.6 KB, 18 views)
File Type: jpg FriedB2competition.jpg (582.4 KB, 32 views)

Last edited by Ro808; 21st July 2017 at 10:09 PM.
  Reply With Quote
Old 21st July 2017, 11:44 PM   #432
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Drivers used in the Fried H2, B2 and C1 Monitor/Satellite Speakers


The Model H/2 used a Dalesford 5" bextere cone mid-woofer (model D30/110) very similar to the KEF B-110 it replaced in the original Model B. The tweeter was a horn loaded soft dome unit by Dynaudio, Model D-28H (so named for the 28mm diameter and the "H" indicates the addition of a Horn/Waveguide). This tweeter has exceptional power handling capability, and allowed Fried to use a first order high pass crossover on the tweeter. It also had a sticky coating, so dust on the dome shows up in the photos.

First Image: The Dalesford D30/110 mid-woofers used in the B/2. Note that Fried applied a label to the rear of the magnet, but left the Dalesford model number on the drivers.

There were several versions of the Dalesford driver used in the first model C and O before Dalesford went belly up.
Fried used a thinner bextrene cone that was more heavily damped with the Plastiflex damping material. This achieved a higher sensitivity by the reduction in cone mass. These also had a larger magnet structure and longer pole piece than the stock versions.

Second Image: Dynaudio D-28H tweeters used in B/2 and C/1. Note again the Fried label on the rear of the driver.

Third Image: Spec sheet for the Dynaudio D-28 tweeter. Note the almost completely flat impedance curve, as the resonance is damped with ferrofluid.


The Dynaudio D-28 is a tweeter I know well.
This is one of the very first hornloaded dome tweeters and - like all Dynaudio products - its construction is top notch, as is the performance. Many of these tweeters are still in operation today and even though its 40 !!! years old, it will easily outperform many contemporary tweeters. Contrary to most Dynaudio woofers, this little gem has a remarkably high sensitivity.
Attached Images
File Type: jpg FriedB2Dalesfordd30-110Woofers.jpg (189.9 KB, 22 views)
File Type: jpg FriedB2DynaudioD-28tweeters.jpg (194.0 KB, 15 views)
File Type: jpg DynaudioD-28specsheet.jpg (312.1 KB, 19 views)

Last edited by Ro808; 22nd July 2017 at 12:11 AM.
  Reply With Quote
Old 22nd July 2017, 07:43 PM   #433
Alex M is offline Alex M  Europe
diyAudio Member
 
Join Date: Apr 2001
Location: Hampshire, UK
Click the image to open in full size.
Here's a new one of Troels's that I have just come across: the MUN-17-3W, which he classifies as one of his "Classic 3-Ways", but goes well beyond even the Audio Technology version. It is an all-ScanSpeak design, with an 11" woofer in a closed box (unusual for Troels), a 6" midrange and a beryllium tweeter. As with several of his larger speaker projects, the bass is driven by an integral Hypex module to take the strain off the MT amplifier.

If I weren't still very happy with my SEAS three-ways (and had a better listening room in a detached house, rather than the awkwardly shaped living room in our suburban terrace), I would be very tempted to start saving for this one...

Alex

Last edited by Alex M; 22nd July 2017 at 07:46 PM.
  Reply With Quote
Old 22nd July 2017, 10:02 PM   #434
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Saw these on his site recently.
Technically, there is little to complain.
However, including the suggested Hypex modules, this is certainly not a bargain.

At least, this new Scan 18M/8631-T00 saves you a lot. It is about 1/3 of the "hailed" Audio Technology driver.
  Reply With Quote
Old 22nd July 2017, 10:24 PM   #435
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Bud Fried vs. Crossovers


Quote from Audioholics President Gene DellaSala with a reply from Dennis Murphy (edited):

"Oh Boy Bud Fried was quite the myth perpetuator. I recall on a phone call with him, he once told me metal drivers are junk and any speaker that doesn't use a first order series crossover and a transmission line enclosure is also junk. He always claimed his speakers measured like a resistor but never furnished the measurements to prove it. He was an interesting character to say the least and he certainly didn't keep his opinions to himself

We did a little study of series vs parallel crossovers (1st order in accordance to Fried Gospel). Ironically you can make the response of either network look identical.

Bud was a big proponent of time-coherent speakers and mocked any designs that used higher order filter response networks. I recall him writing a letter to Stereophile to admit that people prefer the sound of shallow slope time coherent speakers over high order filter network alternatives.

Series crossovers put high demands on inductor DCR which in turn dumps a lot of low frequency energy into the tweeter. My understanding was that Fried used Quasi-Second Order Series crossovers -which would rolloff more rapidly in the first octave and then level out to first order below that. IMO, many of his theories were actually backwards. For better power handling and less strain (especially on the tweeter), smoother and more accurate in-room tonal balance, you want slow roll off through the xover region and then faster roll off out of band."

"The series approach definitely had a pretty steep learning curve, and you have to do it pretty much by hand and instinct. The optimization programs on crossover design software tends to go off into sonic space because there's so much interaction in driver response when you change one component. The current conventional wisdom is that series crossover have no inherent advantage over parallel circuits--both should perform essentially the same if the same transfer function is achieved."


Series crossovers have been around for ages. Gilbert Briggs was quite keen on these. In his book on loudspeakers, he gives series and parallel versions for all crossovers.

Bud also stated he learned about using series resonance crossover circuits from the engineers in Denmark.

Since he was good friends with Saul Marantz who had also used series crossovers in some of his early speaker designs. I think he had received some valuable insight from him about this type of design.



Irving M. "Bud" Fried wrote articles about his thoughts on loudspeakers which are available here
and here


And for those who like to learn more about the Sonitkit speakers, you'll find it here
Attached Images
File Type: jpg C3L XO.jpg (837.4 KB, 15 views)

Last edited by Ro808; 22nd July 2017 at 10:35 PM.
  Reply With Quote
Old 22nd July 2017, 11:28 PM   #436
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Vance Dickason tested the Scan-Speak 6.5 18M/4631T00 Revelator for Voice-Coil Magazine and you can read the article here

Last edited by Ro808; 22nd July 2017 at 11:37 PM.
  Reply With Quote
Old Yesterday, 02:16 AM   #437
system7 is offline system7  United Kingdom
diyAudio Member
 
system7's Avatar
 
Join Date: Aug 2008
Location: Portsmouth UK
I have some files on Bud Fried too...

He liked transmission lines.
He liked first order filters.
Not averse to sloped baffle or time alignment as we call it now.
He used wide bandwidth drivers and tweeters that could handle some excursion. Like the 5" Dalesford bextrene and the Dynaudio D28 tweeter.
He was actually fairly flexible in using series or parallel crossovers.

Series filters were used by Richard Allen and Tandberg quite a lot, IIRC.

Click the image to open in full size.

Click the image to open in full size.

Potentially you can get very flat impedance with them, but this can be done with parallel too. My current interest, as it goes.

These ideas are all part of the pot-pourri of speaker building, IMO. Obviously the shallower the filter, the less you hear it and its resonance. But you then hear more distortion.

Some Bud Fried stuff below, from the "system7" files. The truth is out there!
Attached Images
File Type: jpg Fried Super Monitor.JPG (70.2 KB, 12 views)
File Type: jpg Fried KEF B200 Big Box.JPG (39.9 KB, 15 views)
File Type: jpg Fried C2 Satellite.JPG (57.6 KB, 15 views)
File Type: jpg Fried O2 series filter.JPG (52.6 KB, 15 views)
File Type: jpg Fried Cabinet Cheese-wedge and Mid Transmission lne bass.JPG (34.9 KB, 17 views)
File Type: jpg Damping Fried Transmission Line.JPG (29.1 KB, 17 views)
File Type: jpg Fried C Satellite... I think....JPG (42.3 KB, 19 views)
File Type: jpg Bud Fried Speaker.JPG (23.1 KB, 19 views)
__________________
Best Regards from Steve in Portsmouth, UK.
  Reply With Quote
Old Yesterday, 11:25 AM   #438
Ro808 is offline Ro808  Netherlands
diyAudio Member
 
Join Date: Mar 2010
Thanks Steve, for the backup on Bud

I couldn't find any proof for this, but it is my guess that Dave Wilson got at least some inspiration from the C-monitors in designing the WATT's.
He would have done better with the Dynaudio D-28 instead of the screaming Focal and the roundovers at the baffle edges, instead of his ugly felt pads.

Last edited by Ro808; Yesterday at 11:43 AM.
  Reply With Quote
Old Yesterday, 08:08 PM   #439
system7 is offline system7  United Kingdom
diyAudio Member
 
system7's Avatar
 
Join Date: Aug 2008
Location: Portsmouth UK
Is this a classic monitor? I'm not sure. The Monitor Audio MA7. Not bad for 10 anyway in my local charity shop. And it all works! Comes as a matched pair too, so you can have both tweeters on the inside.

It's actually a very nice speaker with good bass from the 12L reflex box. 5" coated paper fibre bass with 105mm cone. 19mm mylar tweeter, quite like a KEF T27 or Coles 4001K. The tube is 4" x 1 3/8". 6 element filter. 3 coils, 3 capacitors. I'm pretty sure it's a BW3.

It does shriek a bit on trumpets. Definitely something peaky at 3kHz. But very nice and lively sound and great vocals. I think I could tidy it up a bit, but that's for another day.

One bass has a surround that hasn't been glued on quite right, so there is a kink in it. But not broken enough to fix.

It's this idea, isn't it. Vifa PL14WJ-

The simulation allows for the ESR of the Elcap 50V NP capacitors and the unusual 8.5R DC of the tweeter. 6 ohm bass DC. The dotted line on the FR shows the worse response with MKP capacitors. They come with attractive black cloth grilles which given the bright balance work well.
Attached Images
File Type: jpg Monitor Audio MA7.JPG (61.9 KB, 10 views)
File Type: jpg Monitor Audio MA7 Coil test.jpg (90.1 KB, 10 views)
File Type: jpg Monitor Audio MA7 Drivers.jpg (80.0 KB, 9 views)
File Type: png Monitor Audio MA7 FR Simulation.PNG (20.2 KB, 20 views)
File Type: png Monitor Audio Phase simulation.PNG (21.7 KB, 20 views)
File Type: png Monitor Audio MA7 circuit used for simulation.PNG (7.2 KB, 22 views)
File Type: jpg Monitor Audio MA7 Construction.jpg (64.8 KB, 10 views)
__________________
Best Regards from Steve in Portsmouth, UK.

Last edited by system7; Yesterday at 08:20 PM. Reason: Better crossover photo added.
  Reply With Quote

Reply


Classic monitor designs?Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Classic 16.0 Lowrider Tubes / Valves 38 6th August 2008 08:15 AM
efficient (loud) 'monitor'/bookshelf designs for 5.1 Puggie Multi-Way 0 30th May 2006 10:17 AM
Classic BR Alignments BAM Multi-Way 0 20th November 2005 04:31 PM
The A4 monitor, best mini monitor? KURT Multi-Way 5 26th April 2005 01:34 PM


New To Site? Need Help?

All times are GMT. The time now is 04:48 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio
Wiki