Dont like the bb2134 in quad 34,replace them back?

tony71 · 26th April 2006, 10:32 AM

Hello all,

I have a quad 34 preamp thats been to an ingenieur in Holland to replace the opamps.They have been replaced by the OPA134 or OPA2134.
I also have a quad 405-2 who had the opamps replaced by bb 134
When i got the set back i started listening.
It sounded terrible.The high tones were not nice to listen.
I changed the opamps in the 405 back to the tlo71 and also put in the ne 5534 and the sound was a lot better.With both of these opamps.
I think the bb 134 had oscillation...I am not an elektronic expert so i dont know for sure.
But i am not happy after all.The sound is still to sharp.My old marantz preamp (1976 ) sound better then the quad 34...
So now i want to change the opamps back in the quad 34.
Should i do that with the ne series 5534/32/33?
Or the new tl2071 series?
Or stick with the old tl071?
I have 8 tl071cp and 4 tl072cp they were in the quad 34 officially.
Can someone help me and tell me which opamps i have to get?
A replacement for the tl071 and a replacement for the 072cp?

tony71 · 27th April 2006, 11:26 AM

Nobody?

Then i just put the tl071 back in the preamp.
I dont like the high treble that comes out off the set.
Its no fun to listen to.
Is it possibel to place the ne 553xx series in the preamp?
Anyone here ever serviced a quad 405 or 34/44 preamp?

Regards,

Tony

peranders · 27th April 2006, 11:40 AM

Maybe you are not used to how modern opamps sound like but it may also be the case that the OPA134 didn't have optimal wokring conditions.

Personally I think OPA134 is excellent in many places.

PierreG · 27th April 2006, 12:31 PM

I don't want to offend you and I also don't know what your source and speakers are but, maybe it is now more precise and it reveals the flaws of the source.....If it is the case you can borrow a better source and try again with the OPA134.
Just trying to help....

neutron7 · 27th April 2006, 06:06 PM

The newer op amps have quite a lot more bandwith. it could be they are oscillating if the quad was designed for TLO71

peranders · 27th April 2006, 08:01 PM

OPA134 and TL071 are smiliar in speed so I on't think there will not be any stability problems but OPA134 maybe emphasize other shortcomings.

tony71 · 30th April 2006, 01:15 PM

Okay , guys.

Thanks first for you reply`s.
Maybe it is that i am not used to the new opamps.
I am going to listen to some more recordings and decide then what i am going to do.
Everyone i am asking for the advice is very enthousiastic about the bb opamps so i ll give it a try.

Regards,

Tony

405man · 2nd May 2006, 09:15 AM

Did you also have the large number of electrolytic capacitors in the signal path replaced, these deteriorate with age and ultimatly leak causing damage to the PCB

Stuart

tony71 · 2nd May 2006, 03:05 PM

Hello, Stuart.

Thx for your advice.
The ingenieur here in holland also changed the capacitors.
He replaced everything thats aged.
I have listened the 405-2 with another preamp.
A marantz.
Now i am sure.I am going to replace the opamps back in the 34.
I dont like the harsh sound at all.
Maybe its just my ears...

Regards,

Tony

405man · 2nd May 2006, 03:18 PM

I have rebuilt a large number of 34s and 405s using OPA134s this was the comment from the last customer

Hi,
Fired up the amps this morning. They sound fantastic, they're not really warmed up yet either. Great clarity and weight without a hint of harshness. You were right, they work well with the quad speakers. Thanks again, good doing business with you,

Cheers,
Gordon

So I am surprised that you have problems with them. If you replace the opamp in the 405 with the original you may have to replace the capacitor between pins 1 & 8 as it is not required for the OPA134 but may be necessary with the TL071 or LM301 in the 405

Stuart

26th April 2006, 10:32 AM	#1
tony71 diyAudio Member Join Date: Apr 2006 Location: rotterdam	Dont like the bb2134 in quad 34,replace them back? Hello all, I have a quad 34 preamp thats been to an ingenieur in Holland to replace the opamps.They have been replaced by the OPA134 or OPA2134. I also have a quad 405-2 who had the opamps replaced by bb 134 When i got the set back i started listening. It sounded terrible.The high tones were not nice to listen. I changed the opamps in the 405 back to the tlo71 and also put in the ne 5534 and the sound was a lot better.With both of these opamps. I think the bb 134 had oscillation...I am not an elektronic expert so i dont know for sure. But i am not happy after all.The sound is still to sharp.My old marantz preamp (1976 ) sound better then the quad 34... So now i want to change the opamps back in the quad 34. Should i do that with the ne series 5534/32/33? Or the new tl2071 series? Or stick with the old tl071? I have 8 tl071cp and 4 tl072cp they were in the quad 34 officially. Can someone help me and tell me which opamps i have to get? A replacement for the tl071 and a replacement for the 072cp?

27th April 2006, 11:40 AM	#3
peranders Electrons are yellow and more is better! diyAudio Member Join Date: Apr 2002 Location: Göteborg, Sweden Blog Entries: 4	Maybe you are not used to how modern opamps sound like but it may also be the case that the OPA134 didn't have optimal wokring conditions. Personally I think OPA134 is excellent in many places. __________________ /Per-Anders (my first name) or P-A as my friends call me

27th April 2006, 08:01 PM	#6
peranders Electrons are yellow and more is better! diyAudio Member Join Date: Apr 2002 Location: Göteborg, Sweden Blog Entries: 4	OPA134 and TL071 are smiliar in speed so I on't think there will not be any stability problems but OPA134 maybe emphasize other shortcomings. __________________ /Per-Anders (my first name) or P-A as my friends call me

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Back to Back transformers and safety ground	dsavitsk	Tubes / Valves	1	9th February 2009 10:10 PM
back to back coupling capacitors	reddog	Solid State	5	3rd January 2006 06:59 AM
(Attn Planet 10!) active xo & 2.5 way back to back Vifa P13 mids - questions	paulspencer	Multi-Way	9	15th August 2004 05:34 AM
Back to Back Polarized Electro's	EchoWars	Solid State	11	15th November 2003 09:30 PM
Back to Back input diodes	Kevin McCready	Solid State	0	9th September 2002 11:56 PM


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

27th April 2006, 11:26 AM	#2
tony71 diyAudio Member Join Date: Apr 2006 Location: rotterdam	Nobody? Then i just put the tl071 back in the preamp. I dont like the high treble that comes out off the set. Its no fun to listen to. Is it possibel to place the ne 553xx series in the preamp? Anyone here ever serviced a quad 405 or 34/44 preamp? Regards, Tony

27th April 2006, 12:31 PM	#4
PierreG diyAudio Member Join Date: Oct 2004	I don't want to offend you and I also don't know what your source and speakers are but, maybe it is now more precise and it reveals the flaws of the source.....If it is the case you can borrow a better source and try again with the OPA134. Just trying to help....

27th April 2006, 06:06 PM	#5
neutron7 diyAudio Member Join Date: Dec 2003 Location: Toronto Canada	The newer op amps have quite a lot more bandwith. it could be they are oscillating if the quad was designed for TLO71

30th April 2006, 01:15 PM	#7
tony71 diyAudio Member Join Date: Apr 2006 Location: rotterdam	Okay , guys. Thanks first for you reply`s. Maybe it is that i am not used to the new opamps. I am going to listen to some more recordings and decide then what i am going to do. Everyone i am asking for the advice is very enthousiastic about the bb opamps so i ll give it a try. Regards, Tony

2nd May 2006, 09:15 AM	#8
405man diyAudio Member Join Date: Dec 2003 Location: Near Glasgow Scotland	Did you also have the large number of electrolytic capacitors in the signal path replaced, these deteriorate with age and ultimatly leak causing damage to the PCB Stuart

2nd May 2006, 03:05 PM	#9
tony71 diyAudio Member Join Date: Apr 2006 Location: rotterdam	Hello, Stuart. Thx for your advice. The ingenieur here in holland also changed the capacitors. He replaced everything thats aged. I have listened the 405-2 with another preamp. A marantz. Now i am sure.I am going to replace the opamps back in the 34. I dont like the harsh sound at all. Maybe its just my ears... Regards, Tony

2nd May 2006, 03:18 PM	#10
405man diyAudio Member Join Date: Dec 2003 Location: Near Glasgow Scotland	I have rebuilt a large number of 34s and 405s using OPA134s this was the comment from the last customer Hi, Fired up the amps this morning. They sound fantastic, they're not really warmed up yet either. Great clarity and weight without a hint of harshness. You were right, they work well with the quad speakers. Thanks again, good doing business with you, Cheers, Gordon So I am surprised that you have problems with them. If you replace the opamp in the 405 with the original you may have to replace the capacitor between pins 1 & 8 as it is not required for the OPA134 but may be necessary with the TL071 or LM301 in the 405 Stuart

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read