My comments about the RIAA EQ being in the feedback loop of the IC is
based on bench testing. Like yourself, I prefer the sound of passive EQ
when it comes to records & other things. Which, in the case of record
EQ, can be a lot. Time & again, bench testing has proven that the only
thing that belongs in the feedback loop of an IC is, (you guessed it)
How much feedback is up to the designer & how much circuit gain is
required, but you knew that. (I feel like I'm preaching to the choir
here.) Op-amps have come a long way since they & LSI technology were
invented. I have vintage equipment that uses the 709IC. I'm reluctant to
change them for fear of changing the vintage sound.
------ Original Message ------
From: "Gary A. Galo" <[log in to unmask]>
To: [log in to unmask]
Sent: 11/23/2022 5:43:45 PM
Subject: Re: [ARSCLIST] [EXTERNAL] Re: [ARSCLIST] TEAC A-4300SX
>Feedback-based RIAA EQ is not necessarily a bad thing, if it's done properly. While I have a preference for passive RIAA EQ, or a hybrid of passive for the bass portion and active for the treble, there have been any number of very good RIAA preamps designed with feedback RIAA EQ. I've designed a few myself. But, you won't get one that's been designed properly, with high-performance op-amps, for $25 on eBay.
>If you're looking for an inexpensive phono preamp, beware of cheap Chinese knock-off ICs. The ubiquitous 5532 dual op-amp is still incredibly popular in even moderately priced phono preamps because it offers very low noise for very little money. While it's over 45 years old and not my favorite device, quality varies considerably from one IC manufacturer to the next. If you get a phono preamp with 5532 op-amps, be on the safe side and look for NJR or TI devices. If it looks like a Chinese knock-off, avoid it. If you get a preamp from a reputable audio equipment manufacturer, you'll probably be safe.
>Audio Advisor has a wide selection of phono preamps in varying price ranges, including a few from Pro-Ject and Music Hall for around $60 (www.audioadvisor.com). But, any preamp on the low end of the price scale, even purchased from a reputable dealer like Audio Advisor, will necessarily offer performance that's compromised in one way or another. But, related to what I wrote earlier, we have every right to expect that even a lower-end preamp will be free of hum. If you buy something from Audio Advisor, they will allow you to return it if you're not happy.
>Regarding Steve Smolian's comment about cheap phono preamps not having RIAA EQ, I wonder if he can cite any specific models. The only phono preamps I know of that do not have RIAA EQ are those specifically marketed for flat, archival transfers. Diamond Cut Productions sells one of these (www.diamondcut.com). An LP record played on a flat preamp will be difficult to listen to, with screechy treble and no bass.
>From: Association for Recorded Sound Discussion List <[log in to unmask]> On Behalf Of CBAUDIO
>Sent: Wednesday, November 23, 2022 6:47 PM
>To: [log in to unmask]
>Subject: [EXTERNAL] Re: [ARSCLIST] TEAC A-4300SX
>This message did not originate from SUNY Potsdam or one of its trusted senders. Do not open attachments, click on links, or provide your credentials if the source is suspicious.
>I shy away from the cheapies because they use 'jelly bean' IC's, and they typically have the equalization in the feedback loop of the IC.
>Both are a bad idea when it comes to audio fidelity.
>You get what you pay for!
>------ Original Message ------
>From: "Steve Smolian" <[log in to unmask]>
>To: [log in to unmask]
>Sent: 11/23/2022 3:12:33 PM
>Subject: Re: [ARSCLIST] TEAC A-4300SX
>>Br cautious. Some of the inexpensive ones have RIAA equalization, some don't.
>>From: Association for Recorded Sound Discussion List
>><[log in to unmask]> On Behalf Of Railroads On Parade
>>Sent: Wednesday, November 23, 2022 5:15 PM
>>To: [log in to unmask]
>>Subject: Re: [ARSCLIST] TEAC A-4300SX
>>You all got me to look and there was one of those later little Radio Shack preamps for $5 I bid on as this could go into extra innings.
>>On Wed, 23 Nov 2022 at 17:09, Railroads On Parade < [log in to unmask]> wrote:
>>> James, thank you.
>>> I bought the Citation 11 on eBay. It had flaws that have now
>>> floated to the surface.
>>> I was given a Harman Kardon Citation 6 last year and it too has one
>>> channel out.
>>> I like these, Radio Shack used to sell very small ones for $15 when
>>> I was a kid, and they seemed to work just fine.
>>> But anything to handle multiple inputs outputs and tone volume etc
>>> are on eBay, but they ain't cheap.
>>> On Wed, 23 Nov 2022 at 17:04, James Perrett <[log in to unmask]> wrote:
>>>> The Revox A700 and some Philips machines (certainly the N4506,
>>>> N4515 and probably others intended to be used with MFB speakers)
>>>> include phono preamps but most tape machines don't. You can buy
>>>> basic phono preamps for very little money on Ebay which will almost
>>>> certainly work better than trying to kludge something together using the mic inputs.
>>>> On Wed, 23 Nov 2022 at 17:22, Railroads On Parade <
>>>>[log in to unmask]> wrote:
>>>> > One must have an exterior preamplifier to record from a turntable
>>>> > onto this > tape deck, correct? My pre-amp just lost one
>>>> channel, off to the doc.
>>>> > wish someone would tell me my tape deck has a preamp for my >
>>>> turntable during the repair job.
>>>> > Happy Thanksgiving!
>>>> > Guy Walker
>>>> * James Perrett
>>>> * JRP Music Services, Hampshire, U.K.
>>>> * Audio Mastering, Restoration, Recording and Consultancy
>>>> * Phone +44 (0) 777 600 6107
>>>> * e-mail [log in to unmask]
>>>> * http://www.jrpmusic.net