Dx Blame ST - Builder's thread - post pictures, reviews and comments here please.

[dexter]

,iss_man

thanks for the scope pic

can you tell me what's the supply voltage when the amp cliped?

Here is a couple of oscillascope readings of my Blame ST at near clipping and also at clipping. Using 100w 7.5ohm resistor as a load. It had 21.7v ac rms just before clipping so therefore 63w at 7.5ohm load.

Regards

Niss_man

 

[niss_man]

This amp has a gain of 26. So 21.7/26= 0.83v ac input. Supply rails are +/- 36V dc.
You can see the input as the blue colour. Supply rails as green and red (with little bit of ripple from max power usage) and output as yellow line. Supply and output at 10v per division and input at 2v per division. All the information is there.

Regards

Niss_man

 

[ostripper]

Here is a couple of oscillascope readings of my Blame ST at near clipping and also at clipping. Using 100w 7.5ohm resistor as a load. It had 21.7v ac rms just before clipping so therefore 63w at 7.5ohm load.

Regards

Niss_man

Nice O-scope I can't clip mine , no load big enough or speaker big enough to handle it ... But your waveform shows the EXACT reverse of my simulated "ES like" amp (below 1 - 70V rails). This is expected as mine is reversed (bootstrap negative). This shows the simulator reproduces the saturation errata perfectly.

With my 75V rails, my CD/soundcard can not clip the amp even with a 38DB gain , I guess your picture is the only time I will ever see it.
OS

 

[niss_man]

Carlos may have some more scope pictures? I am not sure.

 

[ostripper]

Carlos may have some more scope pictures? I am not sure.

I thank you for those , I really can not get to clip. I would not want to at that power level. Me and MJL21193 just limit total gain where any source input will not drive the amp to clipping (2v rms in = 77v rms out- way too much!!) I trim the input so my woofer won't "bottom out".

I was just curious to see if anything did blow at clipping , you did it and survived. BTW , carlo's amps are the champs with both the sound and for the number people. BX is my favorite sound- wise (ES/st based - below)
OS

 

[niss_man]

I used 2 x 15 ohm resistors rated at 50w. So 7.5ohm 100w resistor. Signal generator used for input. Total output of the amp was 62w. Nothing blew. output resistors got really hot though. May need a bigger test resistor heat sink rather than some scrap aluminium.

Regards

Niss_man

 

[dexter]

do you have any plan for testing blmae amp with 4 ohm load?

btw:
listening impression please

I used 2 x 15 ohm resistors rated at 50w. So 7.5ohm 100w resistor. Signal generator used for input. Total output of the amp was 62w. Nothing blew. output resistors got really hot though. May need a bigger test resistor heat sink rather than some scrap aluminium.

Regards

Niss_man

 

[niss_man]

I need a 4ohm resistor maybe 200w so I can't at the moment. My impressions have been written previously, but again. I have heard the Blame amplifiers called "Friendly" and this I whole heartedly agree on. There is no harshness on the ears anywhere in the frequency range. You get a reproduction as it intended to be. The amps are a pleasure to listen too and are going to be my yardstick to which all others are measured for years to come. There is plenty of power to drive my speakers to very loud levels. I have made a comparison video between ES and ST amps below.

YouTube - Blame ES vs Blame ST

Regards

Niss_man

 

[destroyer X]

Mitchel tested the Dx Blame ST

YouTube - Amplificador DX Blame ST

YouTube - DXBLAMEST

YouTube - Placa de proteção para alto-falantes

YouTube - Surto de Corrente

You have some videos having Brazilian Portuguese language narrative.... but some folks from France, Spain, Portugal and several American countries can understand.

regards,

Carlos

 

[Salas]

You got to design a kit speaker tested and approved by you for going nice with the DX amps series and offer to the fans at a point Carlos. Maybe with Selenium units. Enough of the speakers I some times see on videos can't reveal your amps as much as they deserve in my humble opinion.

 

[destroyer X]

Thank you Salas, this motivates me a lot.

We already have someone to produce nice speakers... folded dipole internal tubes, and good imported drivers... you know, Selenium was sold...now we have imported made in Brasil

What is problematic is that my people will certainly join group buy for that purpose, but, speakers and enclosures are heavy... this is something i feel some sadness, as i cannot go on because of that.

Last week i have sent 12 kilos of electronics to my sons... i have paid 100 USD to the shipment.... this increases to much the price and them the cost turns this operation not very interesting.

But i am really thinking about that... also DIY switching power supplies and power peak meters (in development).

YouTube - Mede potencia e não usa fonte...brinquedo nôvo!

Thank you,

regards,

Carlos

 

[Salas]

You could just provide the assembled crossovers, the cabinet blueprints, and a special price deal for the drivers assortment with a loudspeaker units distributor in Brazil. You will collect and send him the funds and addresses, he will ship. But he will not make or send crossovers. So you can avoid a possible full kit hijack from the dealer. People would have to make their cabinets, or a woodworking shop associate could provide flat pack ready cut and fit grooved panels. Again his shipping.

 

[destroyer X]

That's a very good idea...i will be thinking about that

thank you,

regards,

Carlos

 

[Salas]

Any amplifier is just a servant to the speaker. Caters for it. By creating a speaker that you feel it cooperates to your aspirations for what you feel is the DX voicing and correctly proportioned driving as a package, you will save uncertainty for many fans. Also any tweak you make to the amps you will know how it will translate to the fan's set up. A DX monitor in other words. Just my 2C.

 

[destroyer X]

Yes, for sure is the best way to do... speaker tuned to the amplifier

a system.... this is perfect.

I will manage to do something alike that..but will need some help from Brazilians.

They were already invited to do this... seeds where planted...let's wait them grow....i will be putting water on that and taking care of this seed for a while.

My people loves this stuff...we had group buy for transformer, for heatsinks, for board's kits, for parts to amplifier, condensers and all stuff..... they give up about enclosures because heavy and expensive..was not possible to obtain cheap price....but they love this way..... someone may be interested.

regards,

Carlos

 

[destroyer X]

Even when using a sawn pcboard, it looks good.

At least i like it.

The picture was not very good....my hands are starting to shake...agging effect.

regards,

Carlos

 

[destroyer X]

This is the old Brazilian board for the Dx Blame ST

These boards where distributed, mainly in Brasil and people is finishing to build.

regards,

Carlos

 

[destroyer X]

Dx Blame ST....new pictures

attached,

regards,

Carlos

 

[Jack C.]

Time to thank!
I've finished to build my 2 DX Blame, ST and ES. They work perfectly and the quality of the sound they produce is beyond all hope. I'm admiring: your amp is a masterpiece, Carlos. Many thanks to you, to Metal for his clever design and to Rudi for his enthousiasm and devotion to help and advise.
j

 

[destroyer X]

Merci beaucoup mon cher ami...thank you my dear friend

This is what drives me on...what turns interesting to work the way i use to work producing advertising and providing board's layout and also group buy......because this amplifier (Blameless in the reality) is really very good in sonics.... the best in overall performance i have ever listened too along this 50 years of research.

Thank you.... tjese red boards are lovely.... i have them here, but i had no courage to put solder on it....not to touch this Art Masterpiece....it will be keep untouchable as an example of good cooperative work we had; Rudi ,Metal and me, in the past.

Supercharged boards, the blue boards, were made obbeing my personnal rules and needs...but i could not achieve the manufacturing quality the German group achieved because of price...so....in board features, board quality, the red ones are the best.

Next amplifier.... an amplifier to produce an earthquake....more a demolition tool than an amplifier...the Troyan revisited and redesigned, will have red boards that gonna beat the German group quality..for sure they will.

a bientôt,

Carlos