Mark goes at it again... just bought a PL700/II!

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#21
Mark, I thought you were going to WOPL this amp??? Testing is kinda a moot point since a WOPL will gut it completely...
I tested as far as possible, don’t have a way of measuring THD, power output, etc. I’m just a hobbyist, would love to have a comprehensive checkout both before and after for full comparison.

Yes, I agree- it really is moot, but again, a before and an after is a good thing. Half the purpose of the video is for the first- timers, the other half is to avoid the minor errors of the first “surgery.â€
 

JustMike

Chief Journeyman
Joined
Aug 4, 2014
Messages
885
Location
"wherever she lets me"
Tagline
"Just Passin thru"
#24
Hi ya Mark. Good to see you buddy. Enjoyed your video, but would have liked to have seen the dbt test light go all the way to full bright and then
back to dim. Or was I missing something ?

I would like to hear your opinion on how the Amp sounds now compared to your 400 on the same source and speakers.
The 700 has gain controls so you can control the output if you have a concern that you may over amp your speakers. What speakers do
you have on the 400 now ?
This would be an interesting comparison before you change to WOPL and full comp. on the 700.
You might like what you hear, Fire that baby up man.
The best,
jm
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#25
Hi ya Mark. Good to see you buddy. Enjoyed your video, but would have liked to have seen the dbt test light go all the way to full bright and then
back to dim. Or was I missing something ?

I would like to hear your opinion on how the Amp sounds now compared to your 400 on the same source and speakers.
The 700 has gain controls so you can control the output if you have a concern that you may over amp your speakers. What speakers do
you have on the 400 now ?
This would be an interesting comparison before you change to WOPL and full comp. on the 700.
You might like what you hear, Fire that baby up man.
The best,
jm
The bulb did start bright and dimmed, the auto-exposure on the cheap-o camera probably compensated.

Yeah- an A|B test wouldn't be a bad idea. Worried more about a full 350 watt startup THUMP than anything else, my ears really can't stand full volume from the 400 as it is, so I don't think I'd blast it anyway. No protection circuit installed yet, so I'm a bit cautious.

I have a pair of A|D|S L-1290 towers, a bit grainy and harsh in the midranges, insufficient body to the bass for my liking, but that's what I have. (Considering a Klipsch active subwoofer...)

A friend gave me a pair of Cerwin Vega VS-120, even harsher in the mids, but the bass is a bit better. They're 4Ω, I have 4Ω 50w resistors in series with the speakers and a Pioneer SX-780 in the living room. (Darlington outputs- I don't think they like loads less than 8Ω.)

I took a repair job on a Mackie SR1530 active PA system last month, 15" ported woofer. Bass I could feel in my chest. Horn loaded mid, again, a little harsh. Sparkly tweeter, though. With the comments I've made about midranges, I think it may be time for a hearing test...

My first speakers were the Heathkit version of the AR-3a. Those were nice and smooth, and shook the floor to my satisfaction.

Yeh... smartie idea!
 

JustMike

Chief Journeyman
Joined
Aug 4, 2014
Messages
885
Location
"wherever she lets me"
Tagline
"Just Passin thru"
#27
I think you would be fine . Are there inline fuses on your main speakers ? That adds a little insurance for the tweeters on start-up.
My first original Pl700 series II I bought new in 1978 I think. I still have it but its shelved waiting for an upgrade someday. Still works.
I used it on infinity Monitor Jr.'s, Dahlquist DQ-10's , Bose 301's, Advents , EPI's and Genesis 1's. I never blew a fuse in any of them
or damage a driver from the turn on thump. And it was a thumper!

I'm running two full comps now. One 700II and one 400II bi-amped thru an active crossover.

Have fun Mark, enjoy your rebuilds.
cheers,
jm
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#29
Gepetto;22[IMG said:
http://forums.phxaudiotape.com/attachment.php?attachmentid=32081&stc=1[/IMG]

OY! Such a beauty! I especially like the power connector!
 
Last edited:

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#30
Another shits & giggles video...

Interesting thing about the amp still playing after the power is turned off!

Meter display switch seems to be wired in reverse- isn't -20db supposed to be when the switch is depressed?

Played a few records for an A/B test, but buzz in the 700 muddied the bass, audio was a little harsh compared to the 400. (Not a fair test...)

Requested an invoice for the backplanes today.

<iframe width="560" height="315" src="https://www.youtube.com/embed/7va2v1GnYVQ" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#31
Backplanes fit in the chassis, so a sigh of relief... does White Oak offer mortgaging for a complete upgrade package? (Kidding, of course...)

Backplane kit arrived Monday, today would have been a good day to start- but it seems that whenever I get a kit, I have to buy a new soldering iron. My cheapie-Chinesey crapped out, so I splurged on a Weller this time.

Disappointed, plans for the day interrupted. Guess I’ll put up the window blinds that I bought last month.
 

Gepetto

Administrator
Staff member
Joined
May 15, 2011
Messages
13,473
Location
Sterling, MA
Tagline
Old 'Arn Enthusiast
#32
Backplanes fit in the chassis, so a sigh of relief... does White Oak offer mortgaging for a complete upgrade package? (Kidding, of course...)

Backplane kit arrived Monday, today would have been a good day to start- but it seems that whenever I get a kit, I have to buy a new soldering iron. My cheapie-Chinesey crapped out, so I splurged on a Weller this time.

Disappointed, plans for the day interrupted. Guess I’ll put up the window blinds that I bought last month.
You need a very good high wattage iron for the backplanes Mark. Good move on the upgrade. 80-100W is needed for the SMT nuts.
 

wattsabundant

Chief Journeyman
Joined
Apr 26, 2011
Messages
842
Location
Central Ohio
#33
You need a very good high wattage iron for the backplanes Mark. Good move on the upgrade. 80-100W is needed for the SMT nuts.
I bought one of the import hot air guns that is used for surface mount to do the pem nuts on the back planes. I practiced on a smoked PL14 board before first. It worked pretty good.
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#34
I bought one of the import hot air guns that is used for surface mount to do the pem nuts on the back planes. I practiced on a smoked PL14 board before first. It worked pretty good.
Didn’t give one of those hor air guns a thought, maybe I should have. I bought a 100w gun- type iron for the PEM nuts, so it’s covered. The Weller came today, max is 70w on that, hence the gun type just to make sure. I worked on a surface-mount kit before using a standard pencil iron, that’s an experience I don’t wanna repeat. HATE those suckers!

BTW- I sent an email to you (8/3) requesting an invoice for the relay board... no reply yet. I don’t remember exactly how I ordered the last time, assumed it was the same as for ordering from White Oak. I bought the completed assembly last time, but now I’m in “Invincible Mark†mode, and I’ll order the components from Mouser since you’ve been kind enough to list all the parts!
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#35
You need a very good high wattage iron for the backplanes Mark. Good move on the upgrade. 80-100W is needed for the SMT nuts.
The Weller I bought said 70w, but it did the job with ease- in fact, took care of it pretty fast! First backplane board finished...
(Funny, C1 and C2 absent, BOM said don't populate... Thought I was missing a part(s) at first...)

 

Attachments

Gepetto

Administrator
Staff member
Joined
May 15, 2011
Messages
13,473
Location
Sterling, MA
Tagline
Old 'Arn Enthusiast
#36
The Weller I bought said 70w, but it did the job with ease- in fact, took care of it pretty fast! First backplane board finished...
(Funny, C1 and C2 absent, BOM said don't populate... Thought I was missing a part(s) at first...)

No missing parts Mark. Those are not to be populated.
 

MarkWComer

Veteran and General Yakker
Joined
Nov 1, 2014
Messages
3,198
Location
Gaston, SC
Tagline
Victim of the record bug since age five
#39
Backplanes assembled, didn't do all the wiring yet, and won't until I gut the cabinet and decide if some of the existing wiring really needs to be eliminated.

You experienced guys: The videos are geared for the newbies who are scared of opening up a chassis and modifying their amp. Feel free to critique, correct anything that I speak in error!

Where's Don Imlay been? I poked him for the relay board a while back (August third), no response yet...

<iframe width="560" height="315" src="https://www.youtube.com/embed/ya22qN0EKMU" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen=""></iframe>

(Hmmm... YouTube notes "copyright claim" for the music in the background...)
 
Last edited:

wattsabundant

Chief Journeyman
Joined
Apr 26, 2011
Messages
842
Location
Central Ohio
#40
Backplanes assembled, didn't do all the wiring yet, and won't until I gut the cabinet and decide if some of the existing wiring really needs to be eliminated.

You experienced guys: The videos are geared for the newbies who are scared of opening up a chassis and modifying their amp. Feel free to critique, correct anything that I speak in error!

Where's Don Imlay been? I poked him for the relay board a while back (August third), no response yet...

<iframe src="https://www.youtube.com/embed/ya22qN0EKMU" allow="autoplay; encrypted-media" allowfullscreen="" width="560" height="315" frameborder="0"></iframe>

(Hmmm... YouTube notes "copyright claim" for the music in the background...)
Just sent the invoice for the board.
 
Top