and now for something completely different part 3

[dsavitsk]

On 11/17/2017 at 11:23 AM, dsavitsk said:

Mouser shipping has had issues for a few years now. Packages rarely seem to ship on the day they are supposed to. That said, they always upgrade me to 2 day, or sometimes overnight, to get them here on time.

Yesterday's order ...

Dear -------------;

Your purchase order number -------- is being processed by our warehouse and will ship out on 12/18/2017

We appreciate you placing this order through our website.

You requested your order be shipped by UPS GROUND SERVICE.
To ensure that you receive your order on the day you expected it, Mouser has upgraded your order to ship UPS NEXT DAY AIR at no additional charge to you.

You are a valued customer and we appreciate your business.
If you have any questions, comments, or if we can assist you in any way please let us know.
You can reply directly to this e-mail.

Pretty standard for me at this point.

 

[n_maher]

Something tells me that they treat you a little differently than they treat customers with a less established or consistent ordering history.  Back when I used to regularly order they'd get stuff out on the same day if I ordered in the morning (EST) and rarely it would take until the next business day.  

[Pars]

They aren't nearly as good about this stuff as they used to be. They offer next day shipping as a carrot, and then take 3-4 days to ship the order. My last order, I called and spoke to one of their reps and asked why an order submitted on the weekend had not shipped by late Monday. This was an $80 order. The rep said "with a large order like yours...". Precious, but I told her it was a small order, and that their commercial clients, etc. (and peeps like Doug) place much larger orders than that. Now they did immediately ship the part I got them to add to the order...

[gepardcv]

Arrow has been running a free overnight shipping promotion for a while now. I've been using it instead of Mouser and Digi-Key where possible.

[dsavitsk]

1 hour ago, n_maher said:

Something tells me that they treat you a little differently than they treat customers with a less established or consistent ordering history.

That's probably true.

 

1 hour ago, Pars said:

This was an $80 order. The rep said "with a large order like yours...".

This was a $300 order. There does seem to be a price point, which I have not quite figured out yet, which determines whether they upgrade to 2nd day or overnight. But I have definitely never had them sit on an order and then not upgrade it.

[cspirou]

My brother got free next day shipping on his very first Mouser order. He also lives in Houston and Mouser is based in Dallas so I dont know if that had anything to do with it.

[mwl168]

My last Mouser order was about $450 and I opted for "express" shipping.Placed my ordered on Sunday and it was shipped on Wednesday.

They used to be much better. 

Edited December 23, 2017 by mwl168

[mwl168]

I like the CFA2 so much I want to give it a separate PSU to move the transformer away from the amp circuit. The PSU chassis came in a few days ago.

Still debating if to go dual-mono with 2 GRLV.

 

[jose]

I´ll probe with one and two PSU´s. The amperage of the r-core is small (25volt@1A x 2) so I do not know if one can supply enough voltage to all four channels.

For other hand, I have toroids with secondaries 30volt@3A x2 that I guess can use if it's necessary.

 

 

Edited December 23, 2017 by jose

[jose]

First start... and with music!!!

Thanks Dr. Gilmore!!!!

[jose]

Cold start with matched sand (at 2%) and led's, B= 23,33 Vdc, Bias around 150mVolt (drift a little); I have 35mVolt on both channels (offset). This is very stable, no drift. After 30 minutes, offset is 28mVolt and 29mVolt.

 

Probably with a closed matched the offset can be around 0mvolt.

 

I'm using a Toroidy audio spec. (180VA with 24vAC x2 sec.)

 

I haven't issues with temperature on amp. This afternoon I'll start other two channels but I think that the GRLV will need heatsink in her chassis.

 

 

 

[jose]

On ‎02‎/‎11‎/‎2017 at 3:50 AM, mwl168 said:

Cranked the bias current to 180mA. Broke out my LCD2 as I had a feeling that this amp will be a good match for it. 

People with LCD2 really ought to listen to it driven by this amp at least once just for the experience.

I am still in awe of the speed, clarity, resolution and control of this amp. 

I can understand now why Kevin said in his post that this should be the end-all of dynamic amps. 

This is my favorite of all my dynamic amps and I don't think it's entirely a new toy syndrome at play.

I´m listening to my LCD2 and I´m agreement with your appreciations. I wonder if this amplifier will be more powerful than the Dynahi Bal.

Did you notice any difference between 180mA and 200mA?

 

[mwl168]

Glad to hear that you like the amp as well. Are you running a 2-board SE or 4-board balanced?

For the bias, I only listened to mine (4-board balanced) briefly at 180mA. I then experimented with several combinations as high as 250mA bias and 26 VDC supply rails over a few weeks period and I settled on 22VDC rails and 200mA bias now. Frankly, I just got tired of fiddling with it and want to sit and enjoy listening to music 

I don't have a Dynahi so no way for me to compare. I can tell though my balanced CFA2 is significantly more powerful than my SS Dynalo.

[jose]

I running 4 board balanced.

OK, I´m using 180mA and this sound very well. I'll probably leave it that way definitively.

Yes, sure, my CFA is more powerful than my Dynalo MKI and SS. About Dynahi, I have dudes but CFA is very powerful too. I need compare it when I´ll have time. 

I have a doubt. I would like to use my preamp bal connected to this amp directly. The output impedance is 100 Ohm (typical), Will I have problems ?

 

[kevin gilmore]

Should be just fine

[jose]

6 minutes ago, kevin gilmore said:

Should be just fine

Thanks Dr. Gilmore. 

I will use this for a while until I build my un/bal preamp. 

 

[Helium]

On 25.11.2017 at 6:36 PM, kevin gilmore said:

that is probably close.  ksa5 has a fet input stage.

Kevin, still I have a question about input impedance. Maybe I don't get it right.

There is a diffrence between schematic and PCB silkscreen.

Schematic says R17 is 10K (=input impedance). Board silkscreen says R17 is 1K + 20K. Does it mean that actual input impedance is 21K? Or is it 1K?

I'm trying to figure it out to build relay attentuator. 10K vs 21K is huge difference for proper potentiometer selection.

 

Edited January 14, 2018 by Helium

[kevin gilmore]

The 1k input is to prevent oscillations if you short the input to ground. The 20k is in parallel with the bipolar input stage. So the result is something on the order of 10k input impedance. Maybe a bit less.

[Pars]

On 12/16/2017 at 1:54 PM, Pars said:

They aren't nearly as good about this stuff as they used to be. They offer next day shipping as a carrot, and then take 3-4 days to ship the order. My last order, I called and spoke to one of their reps and asked why an order submitted on the weekend had not shipped by late Monday. This was an $80 order. The rep said "with a large order like yours...". Precious, but I told her it was a small order, and that their commercial clients, etc. (and peeps like Doug) place much larger orders than that. Now they did immediately ship the part I got them to add to the order...

<Mouser rant, pt2> Not holding my breath, but perhaps a change for the better. Placed a large order on Sunday, being careful to either change parts to in stock SKUs or find elsewhere. Contacted them yesterday to change shipping to insured (duh... my mistake), so they changed it to UPS with decent rate. Get an email today that I had gotten the free upgrade to UPS Next Day. Low and behold, order actually shipped today, complete, and is supposed to arrive tomorrow... this assuming the email or article I had read regarding UPS' Louisville hub having shit going on because of the weather.

Now for the fun of checking it all in (something I'd never had to do before recently). Much of it being surface mount, it might take until I start ohming shit out to determine whether they actually shipped all the right stuff or not. 60 some line items, oh joy

Edited January 17, 2018 by Pars

[Kerry]

Oh what joy we inflict on ourselves

[sbelyo]

I once placed an order with them a few years back and chose usps priority to save $3.  When it didn't arrive 4 weeks later they refunded the order.  I re-ordered with UPS and got the stuff a few days later.  Fast forward 2 months a package from Mouser arrives with the original contents via USPS

[mwl168]

Interesting. 

I just received an order from Mouser and they shipped me the 2-gang potentiometer instead of the 1-gang I ordered. 

Now I’ve had a few orders more than $300 worth and never got any free upgrade in shipping. Have to be honest I have never checked my orders to verify everything was shipped correctly. 

[Pars]

On 1/16/2018 at 6:27 PM, Pars said:

<Mouser rant, pt2> Not holding my breath, but perhaps a change for the better. Placed a large order on Sunday, being careful to either change parts to in stock SKUs or find elsewhere. Contacted them yesterday to change shipping to insured (duh... my mistake), so they changed it to UPS with decent rate. Get an email today that I had gotten the free upgrade to UPS Next Day. Low and behold, order actually shipped today, complete, and is supposed to arrive tomorrow... this assuming the email or article I had read regarding UPS' Louisville hub having shit going on because of the weather.

Now for the fun of checking it all in (something I'd never had to do before recently). Much of it being surface mount, it might take until I start ohming shit out to determine whether they actually shipped all the right stuff or not. 60 some line items, oh joy

I know, bad form quoting myself

Order arrived on time today. It appears to have been picked correctly, as long as everything was in the correct bin. Didn't ohm anything out (will do that when I assemble). Damn, is Mouser back on their game? It did take me about an hour to go thru everything against the packing slip.

[jose]

On ‎03‎/‎01‎/‎2018 at 10:07 PM, kevin gilmore said:

Should be just fine

I'm listening my system; Dac, Classé preamp, CFA/bal and the LCD2. All system on Bal connection.

Guys, this is just brutal.

Thanks Dr. Gilmore !! 

I consider that the Dynahi has a more "musical" sound and the CFA/bal has a flatter and more precise sound being a beast in terms of power.

Now I am considering whether to do my unbal/bal or to use the CFA directly using the preamp outputs of my Classé. 

[jose]

My amp module is ready. Now I'm working on a second Psu for the amp (dual-mono) and at the same time I work on the unbal/bal preamp (I have the PSU ready). I want to do a three module system.