DIY Audio Projects Forum
http://www.diyaudioprojects.com/Forum/

Beyma, a Spanish coaxial driver
http://www.diyaudioprojects.com/Forum/viewtopic.php?f=11&t=4835
Page 3 of 4

Author:  mwhouston [ 13 Oct 2015, 16:40 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

Over quite a few months now I have really fallen in love with the Beymas. I think part of the initial resonance problems were just a break in period which may have been overly long. There is no bad habits exhibited by these speakers now. I really do love the sound and are thinking on getting the 15" versions. Slightly more efficient at 99db and a more extended bass response.

I have been running the uPower UX-171A 1920s tube based (Intermezzo) amp with them for a few days now. They play more then loud enough and sound really excellent. 250Hz and down is being handled by the stereo subbies powered by a 50W Class D and passive Xover.
Attachment:
PA143364 (800x563).jpg

Author:  mwhouston [ 19 Oct 2015, 06:44 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

A 6V6 amp I made a short time back has not been getting much air play lately. Lately I have been really enjoying the Beymas. So I brought the two together. I really didnt expect much but thankfully I got a very pleasant surprise. Black Lace (my copy of Suncalc's 6V6 amp) sounds really excellent when driving the Beymas. It plays loud and bass extends down to about 50hz.

I'm keeping Black Lace in for a few more days yet. I suppose this is the beauty of speakers which are extremely efficient. Any amp can drive them and any low power, flea power or uPower amp will always play loud.

In fact I like it so much I have just orderd the 15" version. Bass extension should be even better.

Author:  mwhouston [ 21 Nov 2015, 19:09 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

I have had the 12" concentric Beymas in constant use for quite a few months now and are enjoying them immensely. Currently they are being driven by my better Class D Tripath amp - "Audiophile". First time I tried this there was a little shouting going on on occasions. What has fixed that is two things. Firstly making another Xover to cross to the tweeter earlier at 1600hz and to make the low pass filter 12db\octive instead of 6db. No more shouting and a lot of enjoyment.

Where I loved the Beymas with my new EL84 amp now hooked up to the Class D this amp can really make the woofer section of the speakers move. I have not seen this at similar volumes with the smaller tube amps. Class Ds have output impedance in the milli-ohm region. It may have something to do with it and though my EL84 amp - "Tamarisk" goes down to 24hz the Audiophile would go lower.

I have one of the 15" Beymas in my possession waiting for the other. Then some 140ltr, 15" Beymas will be gracing my #1 listening area.

Author:  mwhouston [ 25 Nov 2015, 06:28 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

Silly me. You would think after 45 years in the business I would be aware of every silly thing I am capable of. But not so. I found my Beymas too bright with my Tripath T4 Class D amp so I made some -7db bads for the tweeters. They should have been -7 up front with the tweeter section being 105db efficient and the 12" woofer section 98db. But for some reason the pads I had in place were -4db. With any of my tube amps (three at the moment) this gave a little sparkle to the top end. The tweeter section being just a little bright and tube amps sweetly mellow at the top. Bring in the 180W Tripath Class D and now everything is too bright.

I made some -7db pads. Now everything sounds better but maybe to better. I have the parts to make a -6db pad for the tweeter. This should bring back a hint of sparkle to the top without sounding bright.

It gets worse. With the -7db pads in initially and now my new EL84 amp providing the "loud" I decided to install the -4db pads. I started the afternoon's listening with the -7pad in place but swapped it for the -4db pad part way through the CD. But I had installed the pad backwards. It was now about a -20db pad across the tweeter. No wonder the music sounded dull and muted. Fortunately I realised what was wrong but not before six tracks were played. I re-fitted the pad and enjoyed a bright and spirited. Classical afternoon.

I'll let you know how it worked out.

Author:  mwhouston [ 25 Nov 2015, 06:29 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

I now have both my 15" Beymas. New speakers are coming.

Author:  mwhouston [ 17 Dec 2015, 16:14 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

Best balance with the tube amps is -6db on the tweeter.

But unleash the beast; my 250W IRS Class D amp is brighter sounding by far than the Tripath amp. The Tripath amp is very analogue sounding and I would never say overly bright but definitely detailed. To get a good balance between bass and treble I had to pad the tweeters down by 9db. A flat balance is 7db so we are only talking 2 more db.

Now I have a 250W Class D amp with a 760W PS capable of delivery 16A continuously with storage caps capable of delivering 700A instantaneously driving 98db efficient 12" speakers. Volume was controlled by my tube preamp. I decided 60s, 70s and 80s Rock on vinyl was the way to go and loud. Dynamic head room was off the planet and there was drive in the music which was intoxicating. Still a little deaf days later.

Author:  Jay53 [ 14 May 2016, 05:30 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

mwhouston wrote:
I now have both my 15" Beymas. New speakers are coming.


Hi !

Any update on your 15" Beyma Coaxials ? i am considering these in a Horn loaded enclosure.

Author:  mwhouston [ 15 May 2016, 03:56 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

I thought I started another thread for the 15". I should then post some images. In the massive boxes I built for the 15" they produce excellent bass and sound glorious. I listen to them for 4 hours every day powered by my 300B and are always impressed by how well they sound.

I think the boxes ended up 170 litres.
Attachment:
image.jpeg

Author:  paolol [ 11 May 2020, 11:20 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

mwhouston wrote:
My DIY speaker buddy Ron did a lot of testing of the Beyma drivers.There were a few critical difference between the testing and the TS figures posted by Beyma. From the test results the speaker box only needs to be 30ltr with a 100mm diameter port @ 136mm long. These speakers will not go super low but will produce weighty articulated bass.

Ron was particularly impressed with the tweeter section. He ran it up and down a number of times from 500hz to 20K listening for dips and peaks which he claims even expensive tweeters will have. The Beyma tweeter section is first class and was extremely linear right through the audible spectrum. Ron believes mid and beyond should sound particularly good.

One thing I was shocked with was the woofer section rolled-off heavily from 2K and beyond. The specs say 4K. WRONG! So now we have a Xover point - 2KHz. Also the tweeter section measured 12ohms and not 16ohms at 2K. So Xovers will be based on 12ohms.

I will have to switchable Xovers - 1st order at 2100KHz and 3rd order at 2K. When using the 0.5W amp 1st order with switchable in and out choke on the woofer. When using any other amps 3rd order.

Why third order? This is one of Ron's little tricks. 3rd order Xover image like hell. He was able to demonstrate this with small gorgeous little three-way bookshelves he made for some one else. On a live orchestral piece the speakers vanished never to return and the room filled full of music. Stunning. The secret is a 3rd order Xover.

I have a box design already and now to get the design of to my box builder - Don.


Hi, I have your same speakers and I would like to ask you 2 questions: 1) Could you please tell me the parameters measured?
2) If you had to redo them, what would you change about your project?
Thanks so much

Author:  mwhouston [ 11 May 2020, 22:06 ]
Post subject:  Re: Beyma, a Spanish coaxial driver

paolol wrote:
mwhouston wrote:
My DIY speaker buddy Ron did a lot of testing of the Beyma drivers.There were a few critical difference between the testing and the TS figures posted by Beyma. From the test results the speaker box only needs to be 30ltr with a 100mm diameter port @ 136mm long. These speakers will not go super low but will produce weighty articulated bass.

Ron was particularly impressed with the tweeter section. He ran it up and down a number of times from 500hz to 20K listening for dips and peaks which he claims even expensive tweeters will have. The Beyma tweeter section is first class and was extremely linear right through the audible spectrum. Ron believes mid and beyond should sound particularly good.

One thing I was shocked with was the woofer section rolled-off heavily from 2K and beyond. The specs say 4K. WRONG! So now we have a Xover point - 2KHz. Also the tweeter section measured 12ohms and not 16ohms at 2K. So Xovers will be based on 12ohms.

I will have to switchable Xovers - 1st order at 2100KHz and 3rd order at 2K. When using the 0.5W amp 1st order with switchable in and out choke on the woofer. When using any other amps 3rd order.

Why third order? This is one of Ron's little tricks. 3rd order Xover image like hell. He was able to demonstrate this with small gorgeous little three-way bookshelves he made for some one else. On a live orchestral piece the speakers vanished never to return and the room filled full of music. Stunning. The secret is a 3rd order Xover.

I have a box design already and now to get the design of to my box builder - Don.


Hi, I have your same speakers and I would like to ask you 2 questions: 1) Could you please tell me the parameters measured?
2) If you had to redo them, what would you change about your project?
Thanks so much


The box stayed at 30ltrs with lots of bracing. I’ll check the other Parameters.

Page 3 of 4 All times are UTC - 6 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/