Welcome, Guest. Please Login or Register
Decware Audio Forums
10/05/22 at 00:51:39†




Pages: 1 2 
Send Topic Print
New ZMA (Read 5571 times)
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #50 - 08/12/22 at 04:10:14
 
Thanks Steve.  I appreciate the challenge.   Smiley  

I'm picking out the parts to put continuous read-out k-type thermocouples on each input transformer so I can monitor it from my listening chair.  Not that I think I can save a transformer before it blows.  I appreciate your conformation that it is the transformers that are protected.  

I do have two large fire extinguishers in my adjacent garage (which is really a machine shop).  But I'd really expect the smoke to escape from the transformer without significant fire.  

Thanks for making great equipment,
Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #51 - 08/12/22 at 10:01:02
 
That is a great idea Carlsbad! Replace the fuse with a thermal breaker. A simple thermister circuit tripping a heavy duty relay opening the mains. I have though of hard wiring ICs and may do so once the system isolation stage is complete.

Don't forget that the amp plate sits in a wooden base. If unattended the overheating transformer will heat that plate to the point of igniting the wood and wala a 🔥
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #52 - 08/12/22 at 10:44:24
 
Carlsbad I'm sure you saw this but I thought I'd bring everybody's attention this thread by BAndrade is a must read as far as modifications go. I know I'm a newbie around here compared to members that have been around Decware for 20 odd years or more. I am constantly finding new information here in the threads.

https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1554416974
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #53 - 08/12/22 at 12:50:38
 
Thanks Bicycle Joe.  I'm a physicist with 40 years of experience.  I don't think I've ever owned anything of significance that I haven't modded.  Badrade makes me look like a bumbling cub scout.  He is my hero.  I read the entire thread and learned from it.  That thread had a ton of great ideas in it.  Next mod for me is the diodes.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #54 - 08/12/22 at 12:55:28
 
JBzen,
I'm not an expert at electrical protection but I work for a large electric utility and I have engineers reporting to me who are experts.  I don't know why high tech protection circuits haven't been integrated into amplifiers.  Decware builds affordable amps that sound great.  Other manufactures are more proud of how much they cost than how they sound and you would think they might incorporate such a design.

At our 1200 MWe generating facility the electrical protection room is the size of a small warehouse and full of relays and circuits that will take open switches as big as a house in microseconds.  

I'll add this to my list of things to research.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
HockessinKid
Seasoned Member
****




Posts: 868
Re: New ZMA
Reply #55 - 08/12/22 at 13:50:53
 
FWIW,

A couple years ago I had the big caps on my ZMA upgraded by Decware. After reading about his extensive modifications in the thread, I asked Badrade a few simple things that could be done to improve SQ on the ZMA. He suggested in addition to upgrading the big capacitors, replace the rear speaker terminals w/ WBT, adding Decware silver RCA inputs, replace the stock IEC w/ a Furtech IEC, and to try some audiophile fuses. I opted for the Synergistic Research Orange fuses.

Anyway Steve was kind enough to handle the modifications, which Decware would not warrant, when the new caps and silver RCA inputs were installed. Combined they made a very noticable improvement to the sound quality. Detail retrieval and musicality was simply off the charts.

Anyway, you can achieve some noticable improvements to an already great amp. FYI, all extra parts were purchased thru Parts Connexion when they had a sale.

HK
Back to top
 
 

Nottingham Interspace TT w/ Dynavector 20x2 LO cart + Modwright PH 9.0X phono OR Modwright modded Cambridge CNX V2 > CSP3-A preamp > ZMA-A amp > PI Audio UberBUSS > Omega SAHO XRS or Caintuck Audio Lii15 Magnum speakers > Snake River Audio & ZenWave cables.
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #56 - 08/12/22 at 14:04:09
 
I'm not sure what all the Decware modifications for the 25th anniversary accomplish. I know what bypassing the attenuator is, I have a on off switch for the tone stack on my Les Paul, so it goes direct out without hitting the T & V attenuators. I only have a vague idea of what Bypassing capacitors and other bypass upgrades really do. Could somebody explain it to me?

I ordered the upgrades and I understand type of metal and connectors make a difference. Why would one want to bypass a capacitor, I understand replacing it with something better or another value preference. I know how to voice an amplifier but why would you want to bypass it. Does this mean take it out of the circuit?
Smiley
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #57 - 08/12/22 at 20:50:40
 
My amp came with the 25th anniv upgrades.  I forgot to mention that upgraded the rca inputs to Klei which is my favorite manafacturer.  

For both interconnect and speaker binding posts I prefer low mass.  I make my own binding posts out of 6n copper that I machine in my shop.  I'll replace the ones in the amp when I do the ones in my speakers.  FYI, 6n copper does not machine well.  It is sticky and gooey and required a lot of patience and very sharp tooling.  Tellurium copper is not a good conductor. Tellurium is added to improve machinability. But manufacturers has figured out it sounds exotic and if they brag like it is good, people will buy it. Stay away from it.

I'm  Just having a busy summer.  

Next weekend I'm climbing Mts. Whitney and Langley.  Last weekend I hiked all 3 days including Mt San Gorgonio on Sunday.  This morning was my easy day:  13.5 miles with only 3000 ft of elevation gain.  Wintertime I get a little more time to work on the gear.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #58 - 08/12/22 at 21:12:10
 
Carsbad Excelsior!
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #59 - 08/13/22 at 13:33:47
 
My summer is full of cycling. Summer miles on the bike easily surpasses the miles on my truck for the entire year. Next month will be a cycle road ride across Utah. So, not much time to tinker with audio gear now.

I'm thinking a latching relay controlled by a heat sensing circuit or even a current sensing loop. Throw that past your associates to see what can be conjured. Anything to eliminate the in-line fuse in a safe unattached manner.

I agree with the low mass ICs. After a couple purchases of interconnet ends online, there seems to be limited/honest advertising of the wares. As an example, material listed as gold plated copper reveals with a simple brush of a file brass.

What about mechanical connectors? Friction cam clamping using silver clad occ copper wire? Eliminates solder/flux issues and connector ends along with the issues of such.
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #60 - 08/13/22 at 14:15:23
 
BJ, explaining the workings of capacitor bypass brings too mind trying to climb a slippery slope.

To put it simply. In a power supply the electrolytic caps are employed to smooth out the ripple produced by the diodes/rectifier. The bypass caps are employed to help block high frequency hash in the smoothed out ripple. The hash is present in the mains and not blocked out by the higher capacitance valued electrolytics.

If anyone else can further expand on this that would be great.
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #61 - 08/13/22 at 15:47:21
 
Maybe Steve can brooch the topic at Decfest, so as the name implies with the bypass capacitor mod nothing is actually being bypassed but a special extra capacitor is being employed to smooth the current hash.

I yearn to get back on the bike. I was doing a major overhaul restoring my 92 Merlin titanium and took it apart and built it back up with fresh bearings and grease in the headset and bottom bracket. Polished the titanium with scotch pads and applied new decals, handlebar tape, and a titanium seat post, with a new Brooks saddle on top.

Because of the pandemic I haven't rode at all, not even once.
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #62 - 08/13/22 at 17:27:48
 
Quote:
Because of the pandemic I haven't rode at all, not even once.


Iím sorry but I donít understand. Can you fill me in?

Thanks, Brad
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #63 - 08/13/22 at 19:24:50
 
I'll take a shot at bypass capacitors.  You need a large capacitor that would cost an arm and a leg to buy a first quality capacitor of that size.  In fact, super high quality capacitors may not even be available in that size because they aren't affordable.   So you buy a moderately priced capacitor.  Lets call it 100uF.  Next you buy a very high quality .1uF capacitor and put it in parallel.  Now you have 100.1uF capacatance, no significant change.  The effect is that the small high quality copacitor brings you some of the speed, clarity, and defintion of a high end capacitor at a fraction of the cost of the same capacator in 100uF.  

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #64 - 08/13/22 at 20:10:45
 
OK. Carlsbad it's a piggyback and somehow the DNA of one capacitor improves the current passing through quality to an audible difference..
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Same Old DD
Seasoned Member
****




Posts: 439
Re: New ZMA
Reply #65 - 08/13/22 at 21:00:06
 
Oops, already answered.
Back to top
 
 

SE84Cs Mono'ed, McIntosh MC2500, Yamaha Pre, Dual TT, Ortofon, JBL2235x4 modded for OB, Visaton B200 OB, Kleenline Power, Revox & Sony R-R
  IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #66 - 08/14/22 at 20:56:51
 
Quote:
Iím sorry but I donít understand. Can you fill me in?

Thanks, Brad


Crickets provided the answer, thanks.

Brad
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #67 - 08/14/22 at 21:13:45
 
Tempest,
I started hiking again in 2020 after 20 years off the raise kids.  I got an inviation to fill a spot on a mt whitney trip that was open because some people had dropped out uncertain about covid.  I had 6 weeks to get in shape.  I never looked back and now I'm about as fit as anyone you'll find on the trail.

Hiking, running, and climbing outdoors allowed me to get through covid with hadly a bump in my lifestyle.  Others have different thoughts and fears.   There is so much fear being spread out there you have so expect that opinions will be all over.  This is America where we value personal freedom and that includes others' decisions on how to deal with covid, so long as their actions don't affect me (or you).

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #68 - 08/14/22 at 22:25:06
 
Jerry,

Very respectable post. Thank you.

And I agree.

You made my point. You did what alot people did. Get outside and enjoy nature, biking, etcÖ.all suddenly became all the more popular during the planned scam-demic scare tragedy. People who stayed in their fear cocoon did zero to actually look into the matter and ignorantly believed the authorities and medical establishment who fell in line and sang from the same sheet of paper as their authoritarian govt masters coerced them into.

This is America indeed, and when someone puts something out there that just screams for a response from those who pay attention, then those people who pay attention are equally entitled to asking questions.

Brad
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #69 - 08/14/22 at 23:00:26
 
By the way, Iím glad you are enjoying your ZMA. Itís a fine example of one of Steveís greatest accomplishments. And I love that youíre digging in to make improvements. I have all the respect for modding a great piece to make it even greater. IMO itís a necessary part of this hobby.

Brad
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #70 - 08/15/22 at 02:39:35
 
Quote:
so as the name implies with the bypass capacitor mod nothing is actually being bypassed but a special extra capacitor is being employed to smooth the current hash.


Not so. The lower value bypass capacitors present a lower impedance to higher frequencies(hash) which are passed to ground eliminating the hash passing to the plates of tubes. The higher value electrolytics smooth out the ripple by shortening the rise and fall times of the ripple.
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #71 - 08/15/22 at 03:02:14
 
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #72 - 08/15/22 at 12:28:40
 
This might help visualize the bypass capacitor's routing. Pic of zkit circuits with anniversary bypass mods in violet.

Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #73 - 08/15/22 at 12:44:39
 
Thanks for the link and the diagram I appreciate it I'll have to sit down with the link and the diagram at the same time and try to follow but it answers a few questions immediately thanks very much.
Smiley
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 5694
Re: New ZMA
Reply #74 - 08/15/22 at 18:27:47
 

The primary reason for "bypassing" the large value electrolytic capacitors with small value polypropylene caps is to handle the quicker demand pulses of the music. †Large caps are slow, small caps are fast. †We are speeding up the amplifiers which bring more resolution to detail.

Steve
Back to top
 
 
WWW   IP Logged
tempest62
Seasoned Member
****


If all else fails,
TURN IT THE HELL UP!

Posts: 171
Re: New ZMA
Reply #75 - 08/15/22 at 18:50:57
 
Steve,

Do the bypass caps also serve to dissipate (to ground) any ďnoiseĒ from the associated large cap?

Brad
Back to top
 
 

Torii MK V-25th A mods, ZR2-25th A mods, ZBIT, CSP3 (to be DIY modded), Custom HR-1ís, Bryston BDA-3 + BDP-2, Brickwall 8, Ansuz conditioning, DHC-1, DSR-3, ZWire, PI Audio diffusion + DIY room treatments // Audeze LCD-4, Norne Audio Silvergarde S3.
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #76 - 08/17/22 at 14:00:17
 
Thanks for chiming in Steve. Your response provokes deeper thought which is great for better understanding the mysterious world.

I may be off my rocker here, but hear goes.

I can understand why electrolytic caps are 'slow' with static time constants being there is more electron/proton bulk to root thru. While poly caps are 'faster' with constants being there is a more thorough static exchange. But, what I don't see is why this would help with the pulse demand? Is not the bypass caps just further smoothing the ripple by targeting with different static time constants?

Anyone?
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #77 - 08/17/22 at 20:09:41
 
Here is a photo of my real time temperature monitoring indication for my power transformers. --Jerry

https://share.icloud.com/photos/037pKZ9FTAEnoQteorW4hovAg
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #78 - 08/18/22 at 12:55:21
 
Nice Jerry! So if I place my hands on your PTs it would take 5 minutes to produce 3rd degree burns Wink
I am going to place this on my plate of upgrades this winter and figure out a trigger to open up the mains in an event of overheating power transformers.
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #79 - 08/18/22 at 14:05:38
 
JBZen could you send me a link for the diagram?
The resolution is not clear enough for me to read the values, the signal path or any of the notes.

I understand the basic theory, but I'd like to trace the signals out

Smiley

Bicycle Joe
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #80 - 08/18/22 at 14:40:08
 
JBzen, I'd like to have a schematic like that for ZMA.  Is that published somewhere?

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #81 - 08/18/22 at 14:51:06
 
JBZen cancel that I found one with better resolution on the DIY audio site from the Zkit
https://www.diyaudio.com/community/threads/some-quick-questions-on-zen-decware-e...
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #82 - 08/18/22 at 15:40:41
 
JBZen,
So the power transformers could burn you if you kept your hand there long enough.  

The transformers are rated for continuous operation at some very high number like 90 deg C (it is in the BAndrade upgrade thread).  So the concern isn't the transformers.  The concern would be overheaing internal components.  Heat is never good for electrical components but beeswax melts at 62 deg C so fancy bypass capacitors would be the first concern.  now that's one reason the transformers are on the outside, so they won't heat the inside much.  While I wish the transformers were cooler, 50 C isn't a concern.

My real reason for the temperature indicators was for tube rolling and bias adjusting so I can easily see if I've made a change that causes a high temperature.  A tube pulling too much current would cause temperature to start going up and you might see it but the real concern is a tube failing to a short that will fail the transformer and that would happen too quickly to see the temperature change.

Temperature trips are not used much in electrical protection circuits although there are thermal overloads in motor control centers that will open up on sustained high current.  Still, I think you would be better off to work on a breaker that would open on high current.  Look at what size fuse you have and design a switch that will open on high current.

The problem you have to overcome is time.  Protection engineers are always looking at how many electrical cycles they can open a circuit in.  Breaker operating times for a short circuit are usually in single digit milliseconds.  Thermal overloads for a higher load are usually in seconds, perhaps 10 to 60 seconds at a high current.  I think it is really the short circuit we have to worry about.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
BicycleJoe Lo-Fi
Seasoned Member
****


It's all in one
note, Just Listen

Posts: 534
Re: New ZMA
Reply #83 - 08/18/22 at 16:06:17
 
Quote:
JBzen, I'd like to have a schematic like that for ZMA. †Is that published somewhere?


Jerry
The Schematic above is from a ZKit and may not be accurate.
I searched my resources and haven't been able to locate a ZMA schematic.
I would think since there has never been a kit for a ZMA it is proprietary.
Maybe Steve can help you out since you already purchased the amp.

Best of Luck
Bicycle Joe
Back to top
 
 

"Once there was a note, pure and easy,playing so free like a breath rippling by,the note is eternal, I hear it, it sees me,forever we blend and forever we die".
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #84 - 08/19/22 at 03:29:37
 
Jerry, my main concern would be keeping a fire from starting in the event of unattended running gear failure. My isolation platform is made entirely of wood. An amp is replaceable without too much disruption in life but home is a different story. Worse would be loss of life.

I too run my gear without protection but always present in the room when on. The only downside is warmup and break in of tweaks where presence is not desired. I use the CXNv2ís unbalanced outputs feeding another amp in my shop so no need to fire up Decware for that. Hence the interest in overheating protection.

Quote:
I can understand why electrolytic caps are 'slow' with static time constants being there is more electron/proton bulk to root thru. While poly caps are 'faster' with constants being there is a more thorough static exchange. But, what I don't see is why this would help with the pulse demand?


Talk about an oxymoron group of words.

I get it!

Back on rocker Smiley
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #85 - 08/22/22 at 00:54:53
 
Update on temperature monitoring:

1.  It is great to be able to glance up and see the temperature at any time.
2.  So watching the temperature build after I turn it on, the highest temperature I've seen is 51 C (123 F).
3.  Of course it will depend on ambient temperture.  I don't have air conditioning here in SoCal by the beach.  Today my temp when I started was 23.6 (74).  
4.  It depends on tubes and bias settings.  Currently I"m running 7027A Tung Sol biased at 50mA.  Rolling back to TS 7581A tonight when I go wash my car and let the amp cool down.
5.  The longest I've run it is about 5 hours (today is 5 hours so far).  Since I don't have a fuse, I turn it off anytime I leave the house, even for a short time (good practice for any tube amp, anyway).
6.  Parts cost about $40 and took an hour to install.  anybody wants to install this send me a PM.


Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #86 - 08/22/22 at 11:04:07
 
Thanks for the update Jerry.

I found a good candidate for a temperature control switch. It has a isolated 30 amp contact relay, 110v input voltage, and 80f degree differential. Looks like a good hub to start with.. Will need some probe tweaking to use system wide.

KETOTEK KT8230 Digital Temperature Controller Thermostat Regulator 120VAC 30A Fahrenheit -22~572℉ Heating Cooling for Incubator Brooder Refrigerator Fermenter Greenhouse Reptile https://a.co/d/4GCKN7K

Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #87 - 08/23/22 at 14:01:01
 
After beating the aged head against the wall, it seems a central controller will be a bit difficult to protect all units from fire simultaneously. There is a couple of 50 amp DC relays in the stash with a AC controller from a transfer switch. That will keep the relay quiet when energized. To keep each component individually protected when connected to the main disconnect DC relay these are the new candidates:

UMLIFE W1209 110-220V Digital Temperature Controller Board Micro Digital Thermostat -50-110įC Electronic Temperature Temp Control Module Switch with 30CM NTC 10K Probe Pack of 3 https://a.co/d/7wRbEGg

This way each DTC will remain active being a drop out relay will be employed connected in series on a separate controll circuit. Makes it much easier to ID the over heated component in the event of the DC relay shut off.. Only displays centigrade. Now to find a good drop out relay and figure connection hardware between components. All the fun in this hobby Smiley
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #88 - 08/23/22 at 21:53:14
 
JBzen,   I still think you're not on the right path trying to protect the transformers with a temperature signal.  Don't get me wrong, I think monitoring temperature is great and I really enjoy it but temperature is by nature a slow change.  By the time temperature raises enough to get to the trip setpoint, the damage will already be done, anything that might catch fire will already be on fire.  

To protect your amp from high energy events, I think you have to monitor current.  And you have to interrupt that current in a few microseconds.   A short circuit causes enough current to cause things to melt.   But the bulk of the transformer will heat up slowly.  

I'd like to see a circuit breaker or a relay that will open on high current in a few milliseconds.   I can't find one for sale.  There are lots of thermal trips.  Those are not to protect against a catastrophic failure.   They are more to protect a motor that is pulling to much current from failure.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
JBzen
Seasoned Member
****




Posts: 781
Re: New ZMA
Reply #89 - 08/24/22 at 10:03:52
 
Jerry, I realize what your saying and agree. I am merely trying to add some protection to limit a chance of fire. Not too concerned on protecting the components from damage. As you, I can repair or replace whatever fails in the amp. Steve knows his amps inside and out and most likely saw many go up in smoke over the years of tinkering perfection. His comment of the main reason the amps are fused is to prevent the PT from catching fire stuck. I think most of the electrical components in his hardwired amps will just fail in short order without incident. On the other hand a shorted PT thru laminted wire failure or any of the PT's circuits shorted could just keep heating up the PT to the point of catching fire.
Don't get me wrong anything can happen to cause a fire but adding a bit of protection will give peace of mind. It's better to have some protection then none. Bypassing the bottleneck created by the glass mains fuse is desirable. Soooo...

I found these that might just due the trick added to the loop:
https://www.ebay.com/itm/274416771984?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&s...

These may also work but not sure on the quality of the contacts:
NTE Electronics R59-2A Thermal Circuit Breaker
Back to top
 
 

AMC CD8b>XO3>Cambridge CXN2>Stokes DAC>Decware silver/occ DIY> Zrock2>CSP2+>SE84 milflex copper 25th>11AWG silver/copper braid>lii Crystal 10 in Huijgen cabinets. Ortofon 2M Bronze>JVC QL-F4>ZP3>Sims isolation. Isolation-AC filtering-Room treatment
  IP Logged
Carlsbad
Seasoned Member
****




Posts: 112
Re: New ZMA
Reply #90 - 09/10/22 at 13:30:01
 
Update on temperature monitoring: † My power transformers temperature stabilizes at about 28 deg C above ambient. † For the first month that was 51 deg C (124 F). †That temp isn't bad at all.

Of course I leave the thermocouple displays powered all the time so I see the temperature go down when I turn off the amp and in the morning it gives me a reading of the ambient in my listening room which has been 23 C (73F) this summer. †51-23=28. †28 is the temperature rise.

Lately we've had a hot spell and my listening room went up to 28C (82F). †My amp peaked out at 56C, again 28C above room temperature. † It takes about 4 hours to reach max temperature but I often have it on much longer than that.

Jerry
Back to top
 
 

Decware ZMA w/ 25th mods, input selector switch
Chord Dave DAC with M-scaler
Innuos Zenith Mk3 streamer fed by EtherRegen
Tekton Encore Speakers
  IP Logged
hvacational0807
Verified Member
**




Posts: 2
Re: New ZMA
Reply #91 - 09/16/22 at 23:37:08
 
Awesome
Back to top
 
 
  IP Logged
Pages: 1 2 
Send Topic Print