Thank you.. Mine is the Integrated version. Bought New in '96.
I've years ago, 'turned' off the inbuilt pre section, substituting a bespoke Triode Pre... As buffer betwixt sources and power Amp.
The Delta Integrated seems as a High gain amp with mediocre Tone sections added. Took a bit of fiddling initially, to compensate for the High input gain of the rascal.
Sound is 100% improved from OEM setup. Quite satisfied actually. Absolutely Do not need 'improved' Bass 🙂
Was just wondering on the PS caps as they are starting to give preview symptoms of charging issues on turn on.
Yhis is why it was good choice to mate 290 with passive pre.
Sound was good indeed and I could change it by manipulating capacitor mix on b1.
So all should I do is to change electrolytic caps. Those big stock are rubicon. What would be better than this ?
Sound was good indeed and I could change it by manipulating capacitor mix on b1.
So all should I do is to change electrolytic caps. Those big stock are rubicon. What would be better than this ?
There's no problem with Rubycon, Panasonic, Nippon Chemicon, Elna, Nichicon or any decent commercial quality cap that is rated for conventional power supply use with a ripple current rating to at least the amplifier's maximum current demand. A popular and excellent industry standard is the current Panasonic TSHA grade but equivalents in other top brands will be OK too.
Some people just prefer the sound of different brand names but really, the specifications and ratings tell you all that is necessary, short of really expensive and exotic construction caps. To justify their cost, you would be dreaming of also a really expensive amplifier to use it with. I don't think you'll get quite the same value for money using high-end bits in the Delta 290, though. If the amplifier runs hot inside, it might be advisable to use 105 deg. temp. rated caps rather than standard 85 deg. if you plan to keep and use it for long periods.
Some people just prefer the sound of different brand names but really, the specifications and ratings tell you all that is necessary, short of really expensive and exotic construction caps. To justify their cost, you would be dreaming of also a really expensive amplifier to use it with. I don't think you'll get quite the same value for money using high-end bits in the Delta 290, though. If the amplifier runs hot inside, it might be advisable to use 105 deg. temp. rated caps rather than standard 85 deg. if you plan to keep and use it for long periods.
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It is true price of the amp in relation to upgrades planned should be considered. I would sell it long time ago but just want to see theceffect of small upgrades.
Thank you Ian Finch.
I agree, no Audio Weenie exotics intended.
Just current 'quality' as in not Fabrique en Chine caps will do Just Fine.
Heat issue mentioned seemed as odd to me, as My unit has always run cool, barely warm is as hot as it's ever gotten.
Could be my light load speakers as a guess, but those remain as permanent residents.
I agree, no Audio Weenie exotics intended.
Just current 'quality' as in not Fabrique en Chine caps will do Just Fine.
Heat issue mentioned seemed as odd to me, as My unit has always run cool, barely warm is as hot as it's ever gotten.
Could be my light load speakers as a guess, but those remain as permanent residents.
you dont you use it as bass amp and get another amp for high frequencies ? a tube amplifier maybe ?
That's fine, I said "if it runs hot..." because I don't own one and only repaired one Delta 290 that I recall. I'm cautious because a lot of similar UK designs run hot at the output stage due to minimal heatsinking. Mosfet designs moreso.
Owners sometimes increase bias (simply because they can) and components deteriorate sooner because of the higher temp. When there is little extra cost involved, a higher electrolytic temp. rating is often a wise, longlife precaution. Otherwise it may be unnecessary, as you say.
B1 is a buffer. This is an active circuit using semiconductors to condition the signal.
A passive pre is a sole and lonely potentiometer to adjust volume level.
A B1 can be added after the potentiometer to create a buffered volume adjustment.
A passive pre is a sole and lonely potentiometer to adjust volume level.
A B1 can be added after the potentiometer to create a buffered volume adjustment.
HI , recomended opamps to swap the NE5332 and 5334 on this amp ? i dont like how bass sounds and would like to improve it
You'll be hard pressed to improve on the technical performance of NE5532 and 5534, particularly the low-noise, non-TI versions. If you are just thinking of rolling opamps to get a different sound effect from say, a larger impedance difference, then FET input opamps like OPA 134, 2134 or OPA 2604 would make a good starting point for experimentation in the preamp /tone control section.
There's a single 5534 operating as DC servo controller in the amplifier. Don't touch it, because it doesn't pass audio and it will be difficult to re-establish DC balance if you simply swap FET for BJT opamps.
It's unlikely that you will change bass by changing opamps this way but this is subjective assessment, so anything may seem to make a difference, even the higher harmonics of bass instruments that appear in the treble register. Have fun!
There's a single 5534 operating as DC servo controller in the amplifier. Don't touch it, because it doesn't pass audio and it will be difficult to re-establish DC balance if you simply swap FET for BJT opamps.
It's unlikely that you will change bass by changing opamps this way but this is subjective assessment, so anything may seem to make a difference, even the higher harmonics of bass instruments that appear in the treble register. Have fun!
output stage TL072 would make a big improvement, 2 single bb 627 seems the right place to improvise
as the 2 10uf BP caps coupling the pre !
the 2 ne5532 which drive Bass and treble on tone stage can be bypassed by the "straight" switch aswell ! or changed BB 1656
as the 2 10uf BP caps coupling the pre !
the 2 ne5532 which drive Bass and treble on tone stage can be bypassed by the "straight" switch aswell ! or changed BB 1656