DIY audio: what are you building?

[RankStranger]

13 hours ago, mwhouston said:

Diy, a blessing and a curse. For a very long time now i have lived by a DIY mantra - “ if you can build it then you must”. Which means i can’t buy any commercial gear if I have the ability to make it.
 

For example of things i have made over 50 years;- tube and SS power amps, tube and SS preamps, tube and SS phono stages, many speakers, music servers, tube and SS headphone amps both home station and portable and DACs. Not to mention, speaker wires and interconnects. 
 

OK above is the blessing but here is the curse. Because I stick strictly to the above mantra I cant buy two pairs of speakers I would love to hear in my system. Thats it, only two pairs of speakers, you would think I would brake the mantra and buy the bloody things. But no! 
 

The speakers are a pair of Zus ( I'm easy on the model) and Heresy IVs. Thats it. Can’t  do it. I can afford to and have the room but I’m stuck. On another note I did change the woofer in my old 12” Beyma boxes and now run a 12” ploy cone, FaitalPro Tratrix horn with FailtalPro compression drivers I am very, very happy with the results.  Still would love the Zus or Heresys. Blessed DIY. 

nothing good ever came of dogmatic adherence to arbitrary rules. 
 

live your life. Treat yourself  

[mwhouston]

Some months back i posed the question how much capacitive storage and filtering is too much. The question is aimed more at SS amps which can have in excess of 250,000uf of storage and wondered if excessive caps degrade performance rather than enhanced it. I put forward that caps with a big voltage head room may have more sonic advantages than caps installed at near max operating voltages. A few agreed.

 

My 300W Holton has a total of 80,000uf of 100V caps and plays at good volume for 20 seconds once turned off. I consider the 80,000uf here enough.

 

Todays pondering (yes im retired and plenty of time to ponder all sorts of trivia) what is excessive transformer rating for a given SS amp considering maximum rated power. When you consider most of the time our 300W amps are being called on to deliver wattages way below their rating.  I understand even with low efficiency speakers most amps only have to provide about 30W. My speakers are 90db efficient and probably only need 20W or less.
 

Is a 1000VAC tranni (bloody heavy to start with) way over specced for a 300W max(600W both channels driven with a sine wave) amp. Or do you consider that about right. My 300W Holton has a 625VAC tranni perfect for an 8ohm load but where the amp can deliver 500W into 4 the tranni would not make it. 500W peaks for sure.  300W into my high efficiency speakers would cause ear bleeds so 500W os out of the question.

 

The question is;- way over specced trannies  rule or more moderate pairing should govern choice? 

[itsparks]

10 minutes ago, mwhouston said:

Some months back i posed the question how much capacitive storage and filtering is too much. The question is aimed more at SS amps which can have in excess of 250,000uf of storage and wondered if excessive caps degrade performance rather than enhanced it. I put forward that caps with a big voltage head room may have more sonic advantages than caps installed at near max operating voltages. A few agreed.

 

My 300W Holton has a total of 80,000uf of 100V caps and plays at good volume for 20 seconds once turned off. I consider the 80,000uf here enough.

 

Todays pondering (yes im retired and plenty of time to ponder all sorts of trivia) what is excessive transformer rating for a given SS amp considering maximum rated power. When you consider most of the time our 300W amps are being called on to deliver wattages way below their rating.  I understand even with low efficiency speakers most amps only have to provide about 30W. My speakers are 90db efficient and probably only need 20W or less.
 

Is a 1000VAC tranni (bloody heavy to start with) way over specced for a 300W max(600W both channels driven with a sine wave) amp. Or do you consider that about right. My 300W Holton has a 625VAC tranni perfect for an 8ohm load but where the amp can deliver 500W into 4 the tranni would not make it. 500W peaks for sure.  300W into my high efficiency speakers would cause ear bleeds so 500W os out of the question.

 

The question is;- way over specced trannies  rule or more moderate pairing should govern choice? 

What about a Class a 100watt amp using 2 IFXn devices ?   

[Mark_A_W]

Just some little PC speakers.   Focal, Minidsp, Rotel...and CNC.

Working From Home setup.
 

 

Edited April 21, 2021 by Mark_A_W
Better pics

[aussievintage]

59 minutes ago, mwhouston said:

Some months back i posed the question how much capacitive storage and filtering is too much. The question is aimed more at SS amps which can have in excess of 250,000uf of storage and wondered if excessive caps degrade performance rather than enhanced it. I put forward that caps with a big voltage head room may have more sonic advantages than caps installed at near max operating voltages. A few agreed.

 

My 300W Holton has a total of 80,000uf of 100V caps and plays at good volume for 20 seconds once turned off. I consider the 80,000uf here enough.

 

Todays pondering (yes im retired and plenty of time to ponder all sorts of trivia) what is excessive transformer rating for a given SS amp considering maximum rated power. When you consider most of the time our 300W amps are being called on to deliver wattages way below their rating.  I understand even with low efficiency speakers most amps only have to provide about 30W. My speakers are 90db efficient and probably only need 20W or less.
 

Is a 1000VAC tranni (bloody heavy to start with) way over specced for a 300W max(600W both channels driven with a sine wave) amp. Or do you consider that about right. My 300W Holton has a 625VAC tranni perfect for an 8ohm load but where the amp can deliver 500W into 4 the tranni would not make it. 500W peaks for sure.  300W into my high efficiency speakers would cause ear bleeds so 500W os out of the question.

 

The question is;- way over specced trannies  rule or more moderate pairing should govern choice? 

 

How often do you play 1000 watts continuous into speakers?

[mwhouston]

1 minute ago, aussievintage said:

 

How often do you play 1000 watts continuous into speakers?

Only on Fridays of the odd months between 3 and 4pm as long as its not raining. 

[RankStranger]

1 hour ago, Mark_A_W said:

Just some little PC speakers.   Focal, Minidsp, Rotel...and CNC.

Working From Home setup.
 

 

that’s extremely impressive, Mark. Your own design or were you working from plans?

[Mark_A_W]

My own design.    Fully active with Minidsp (2 off 2x4s) and a 6 Channel Rotel amp.

The box is a tad small for the 8" woofers, but they needed to fit on the desk.    They are massive overkill for PC speakers. 

But once you start building...it's hard to stop.  

 

Step 1: Design CNC Router

Step 2: Build CNC Router
Step 3: Buy Mill and convert to CNC
Step 4: Design speakers in MCAD and Speaker CAD (I like Vituix CAD now, I used to use Speaker Workshop.  Bought and tried SoundEasy, but never got on top of it.)
Step 5: Buy MDF...

[acg]

On 21/04/2021 at 3:53 PM, Mark_A_W said:

They are massive overkill for PC speakers. 

 

No such thing...

[AccuTidal]

On 21/04/2021 at 10:56 AM, itsparks said:

What about a Class a 100watt amp using 2 IFXn devices ?   

I would love to have a work-bench like that.  Though the stuffs/oscilloscopes on top shelves will require me going back to school for operation and interpretation.  

[itsparks]

9 hours ago, Chanh said:

I would love to have a work-bench like that.  Though the stuffs/oscilloscopes on top shelves will require me going back to school for operation and interpretation.  

Naw, its called learn as you go and have fun, the scope isn't that hard to use at all actually. 

[mwhouston]

18 hours ago, Chanh said:

I would love to have a work-bench like that.  Though the stuffs/oscilloscopes on top shelves will require me going back to school for operation and interpretation.  

I had a very good super quiet digital CRO which required a laptop. But i hit it with too many volts one day and it stopped working. I bought another but it is so noisy i cam cant do some of the tests i use to. 

[aussievintage]

17 minutes ago, mwhouston said:

I had a very good super quiet digital CRO which required a laptop. But i hit it with too many volts one day and it stopped working. I bought another but it is so noisy i cam cant do some of the tests i use to. 

 

Since you have purchased two of them,  what are your thoughts on what to buy - especially at the cheaper end.

[mwhouston]

11 minutes ago, aussievintage said:

 

Since you have purchased two of them,  what are your thoughts on what to buy - especially at the cheaper end.

I cant recommend the second amd the first is no longer available.  The first i got from Jaycar many years ago plus free software and was excellent. The second is barely usable. I have to get something more serious. 

[mwhouston]

Finally got some good listening time with the new chip based MM phono stage (will be labeled “Mimic - Custom”). Such a simple cct. and produces such good bass and really neutral mids and treble. Staggering dynamics, snappy and fast. An absolute delight to listen to. 

[mwhouston]

Bought one of these MTesters late last year. It failed a few months back. Bought another but used the same enclosure, cheaper. Works OK. This time mounted the battery on the outside for easy change. 

[itsparks]

10 minutes ago, mwhouston said:

Bought one of these MTesters late last year. It failed a few months back. Bought another but used the same enclosure, cheaper. Works OK. This time mounted the battery on the outside for easy change. 

Have one too, they work well.

[AccuTidal]

Guys..,

Been tidying up. 

I have these available if anyone of you would like to obtain the lot locally. 
Arduino board and couple led display screens. Some film caps as per picture. 
Can collect from my office in Joondalup or in Morley WA. 

Audyn, Solon, and Conrad Johnson from one of my preamps that I decommissioned sometime back. 
 

I will also have a couple regulated psu made available too, those I bought from eBay. 

Update: taken by local SNAer. 

 

Edited May 1, 2021 by AccuMagi

[mwhouston]

Does anyone have one of these and can comment?

 

https://www.aliexpress.com/item/1005002112067686.html?ug_edm_item_id=1005002112067686&edm_click_module=alg_product_l1r2_5727164090&creative_img_ind=1&creative_img_tpl=154002&tracelog=rowan&rowan_id1=aeug_edm_16198_1_en_US_2021-04-30&rowan_msg_id=retrCOWS_214_$072980d882ab4b4e90c6064ffa3d608f&ck=in_edm_other

 

[betocool]

19 hours ago, mwhouston said:

Does anyone have one of these and can comment?

 

https://www.aliexpress.com/item/1005002112067686.html?ug_edm_item_id=1005002112067686&edm_click_module=alg_product_l1r2_5727164090&creative_img_ind=1&creative_img_tpl=154002&tracelog=rowan&rowan_id1=aeug_edm_16198_1_en_US_2021-04-30&rowan_msg_id=retrCOWS_214_$072980d882ab4b4e90c6064ffa3d608f&ck=in_edm_other

 

 

For 25$ it's worth the risk I guess...

 

Cheers,

 

Alberto

[Ihearmusic]

On 01/05/2021 at 2:27 PM, mwhouston said:

Does anyone have one of these and can comment?

 

https://www.aliexpress.com/item/1005002112067686.html?ug_edm_item_id=1005002112067686&edm_click_module=alg_product_l1r2_5727164090&creative_img_ind=1&creative_img_tpl=154002&tracelog=rowan&rowan_id1=aeug_edm_16198_1_en_US_2021-04-30&rowan_msg_id=retrCOWS_214_$072980d882ab4b4e90c6064ffa3d608f&ck=in_edm_other

 

I think if you are serious about your hobby the answer is NO!

My capacitance,impedance meter alone cost $200.-. 

Cheap crap like that should not be allowed to be sold. Resources were dug out of the ground, energy has been used, pollution created to make s..t tools to be used for a short period of time just to end up in land fill.

Buy quality that performs and lasts you for a long time.

[RoHo]

On 01/05/2021 at 4:27 PM, mwhouston said:

Does anyone have one of these and can comment?

 

https://www.aliexpress.com/item/1005002112067686.html?ug_edm_item_id=1005002112067686&edm_click_module=alg_product_l1r2_5727164090&creative_img_ind=1&creative_img_tpl=154002&tracelog=rowan&rowan_id1=aeug_edm_16198_1_en_US_2021-04-30&rowan_msg_id=retrCOWS_214_$072980d882ab4b4e90c6064ffa3d608f&ck=in_edm_other

 

Why not get a similar one from Jaycar?  I use a multimeter and LCR meter from Jaycar and haven't had any problems with them.  

[kukynas]

Main issue with these cheapo mm is safety and protection circuit, check some of the YT videos of their td, if you want cheaper but decent mm look at the uni-t or similar

[RoHo]

1 hour ago, kukynas said:

Main issue with these cheapo mm is safety and protection circuit, check some of the YT videos of their td, if you want cheaper but decent mm look at the uni-t or similar

They look just like the ones I use, bought from Jaycar.  Probably OEM and sold under a number of brand names.

[mwhouston]

1 hour ago, RoHo said:

Why not get a similar one from Jaycar?  I use a multimeter and LCR meter from Jaycar and haven't had any problems with them.  

The Mtest goes waaaaayyyy... beyond that.